Publikationen | Origins-Cluster (2024)

RU-D

Astronomy and Astrophysics(03/2021)doi:10.1051/0004-6361/202038381

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To understand the history and formation mechanisms of galaxies, it is crucial to determine their current multidimensional structure. In this work, we focus on the properties that characterise stellar populations, such as metallicity and [α/Fe] enhancement. We devised a new technique to recover the distribution of these parameters using spatially resolved, line-of-sight averaged data. Our chemodynamical method is based on the made-to-measure framework and results in an N-body model for the abundance distribution. Following a test on a mock data set we found that the radial and azimuthal profiles were well-recovered, however, only the overall shape of the vertical profile matches the true profile. We applied our procedure to spatially resolved maps of mean [Z/H] and [α/Fe] for the Andromeda Galaxy, using an earlier barred dynamical model of M 31. We find that the metallicity is enhanced along the bar, with a possible maxima at the ansae. In the edge-on view, the [Z/H] distribution has an X shape due to the boxy/peanut bulge; the average vertical metallicity gradient is equal to −0.133 ± 0.006 dex kpc⁻¹. We identify a metallicity-enhanced ring around the bar, which also has relatively lower [α/Fe]. The highest [α/Fe] is found in the centre, due to the classical bulge. Away from the centre, the α-overabundance in the bar region increases with height, which could be an indication of a thick disc. We argue that the galaxy assembly resulted in a sharp peak of metallicity in the central few hundred parsecs and a more gentle negative gradient in the remaining disc, but no [α/Fe] gradient. The formation of the bar leads to the re-arrangement of the [Z/H] distribution, causing a flat gradient along the bar. Subsequent star formation close to the bar ends may have produced the metallicity enhancements at the ansae and the [Z/H] enhanced lower-α ring.

JCAP(03/2021)e-Print:2103.08672doi:10.1088/1475-7516/2021/10/064

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RES-NOVA is a new proposed experiment for the investigation of astrophysical neutrino sources with archaeological Pb-based cryogenic detectors. RES-NOVA will exploit Coherent Elastic neutrino-Nucleus Scattering (CEνNS) as detection channel, thus it will be equally sensitive to all neutrino flavors produced by Supernovae (SNe). RES-NOVA with only a total active volume of (60cm)3 and an energy threshold of 1 keV will probe the entire Milky Way Galaxy for (failed) core-collapse SNe with > 3σ detection significance. The high detector modularity makes RES-NOVA ideal also for reconstructing the main parameters (e.g. average neutrino energy, star binding energy) of SNe occurring in our vicinity, without deterioration of the detector performance caused by the high neutrino interaction rate. For the first time, distances <3kpc can be surveyed, similarly to the ones where all known past galactic SNe happened. We discuss the RES-NOVA potential, accounting for a realistic setup, considering the detector geometry, modularity and background level in the region of interest. We report on the RES-NOVA background model and on the sensitivity to SN neutrinos as a function of the distance travelled by neutrinos.

Astronomy and Astrophysics(03/2021)doi:10.1051/0004-6361/202039724

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Context. High-redshift quasars signpost the early accretion history of the Universe. The penetrating nature of X-rays enables a less absorption-biased census of the population of these luminous and persistent sources compared to optical/near-infrared colour selection. The ongoing SRG/eROSITA X-ray all-sky survey offers a unique opportunity to uncover the bright end of the high-z quasar population and probe new regions of colour parameter space.
Aims: We searched for high-z quasars within the X-ray source population detected in the contiguous ~140 deg² field observed by eROSITA during the performance verification phase. With the purpose of demonstrating the unique survey science capabilities of eROSITA, this field was observed at the depth of the final all-sky survey. The blind X-ray selection of high-redshift sources in a large contiguous, near-uniform survey with a well-understood selection function can be directly translated into constraints on the X-ray luminosity function (XLF), which encodes the luminosity-dependent evolution of accretion through cosmic time.
Methods: We collected the available spectroscopic information in the eFEDS field, including the sample of all currently known optically selected z > 5.5 quasars and cross-matched secure Legacy DR8 counterparts of eROSITA-detected X-ray point-like sources with this spectroscopic sample.
Results: We report the X-ray detection of eFEDSU J083644.0+005459, an eROSITA source securely matched to the well-known quasar SDSS J083643.85+005453.3 (z = 5.81). The soft X-ray flux of the source derived from eROSITA is consistent with previous Chandra observations. The detection of SDSS J083643.85+005453.3 allows us to place the first constraints on the XLF at z > 5.5 based on a secure spectroscopic redshift. Compared to extrapolations from lower-redshift observations, this favours a relatively flat slope for the XLF at z ~ 6 beyond L_*, the knee in the luminosity function. In addition, we report the detection of the quasar with LOFAR at 145 MHz and ASKAP at 888 MHz. The reported flux densities confirm a spectral flattening at lower frequencies in the emission of the radio core, indicating that SDSS J083643.85+005453.3 could be a (sub-) gigahertz peaked spectrum source. The inferred spectral shape and the parsec-scale radio morphology of SDSS J083643.85+005453.3 indicate that it is in an early stage of its evolution into a large-scale radio source or confined in a dense environment. We find no indications for a strong jet contribution to the X-ray emission of the quasar, which is therefore likely to be linked to accretion processes.
Conclusions: Our results indicate that the population of X-ray luminous AGNs at high redshift may be larger than previously thought. From our XLF constraints, we make the conservative prediction that eROSITA will detect ~90 X-ray luminous AGNs at redshifts 5.7 < z < 6.4 in the full-sky survey (De+RU). While subject to different jet physics, both high-redshift quasars detected by eROSITA so far are radio-loud; a hint at the great potential of combined X-ray and radio surveys for the search of luminous high-redshift quasars.

MIAPbP

Journal of High Energy Physics(03/2021)doi:10.1007/JHEP03(2021)262

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We give a double copy construction for the symmetries of the self-dual sectors of Yang-Mills (YM) and gravity, in the light-cone formulation. We find an infinite set of double copy constructible symmetries. We focus on two families which correspond to the residual diffeomorphisms on the gravitational side. For the first one, we find novel non-perturbative double copy rules in the bulk. The second family has a more striking structure, as a non-perturbative gravitational symmetry is obtained from a perturbatively defined symmetry on the YM side.At null infinity, we find the YM origin of the subset of extended Bondi-Metzner-Sachs (BMS) symmetries that preserve the self-duality condition. In particular, holomorphic large gauge YM symmetries are double copied to holomorphic supertranslations. We also identify the single copy of superrotations with certain non-gauge YM transformations that to our knowledge have not been previously presented in the literature.

Monthly Notices of the Royal Astronomical Society(03/2021)doi:10.1093/mnras/staa3634

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Young dense massive star clusters are promising environments for the formation of intermediate mass black holes (IMBHs) through collisions. We present a set of 80 simulations carried out with NBODY6++GPU of 10 models of compact $\sim 7 \times 10^4 \, \mathrm{M}_{\odot }$ star clusters with half-mass radii R_h ≲ 1 pc, central densities $\rho _\mathrm{core} \gtrsim 10^5 \, \mathrm{M}_\odot \, \mathrm{pc}^{-3}$ , and resolved stellar populations with 10 per cent primordial binaries. Very massive stars (VMSs) up to $\sim 400 \, \mathrm{M}_\odot$ grow rapidly by binary exchange and three-body scattering with stars in hard binaries. Assuming that in VMS-stellar black hole (BH) collisions all stellar material is accreted on to the BH, IMBHs with masses up to $M_\mathrm{BH} \sim 350 \, \mathrm{M}_\odot$ can form on time-scales of ≲15 Myr, as qualitatively predicted from Monte Carlo MOCCA simulations. One model forms an IMBH of 140 $\mathrm{M_{\odot }}$ by three BH mergers with masses of 17:28, 25:45, and 68:70 $\mathrm{M_{\odot }}$ within ∼90 Myr. Despite the stochastic nature of the process, formation efficiencies are higher in more compact clusters. Lower accretion fractions of 0.5 also result in IMBH formation. The process might fail for values as low as 0.1. The IMBHs can merge with stellar mass BHs in intermediate mass ratio inspiral events on a 100 Myr time-scale. With 10⁵ stars, 10 per cent binaries, stellar evolution, all relevant dynamical processes, and 300 Myr simulation time, our large suite of 80 simulations indicate another rapid IMBH formation channel in young and compact massive star clusters.

Monthly Notices of the Royal Astronomical Society(03/2021)doi:10.1093/mnras/staa3860

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Planets form in discs of gas and dust around stars, and continue to grow by accretion of disc material while available. Massive planets clear a gap in their protoplanetary disc, but can still accrete gas through a circumplanetary disc. For high enough accretion rates, the planet should be detectable at infrared wavelengths. As the energy of the gas accreted on to the planet is released, the planet surroundings heat up in a feedback process. We aim to test how this planet feedback affects the gas in the coorbital region and the accretion rate itself. We modified the 2D code FARGO-AD to include a prescription for the accretion and feedback luminosity of the planet and use it to model giant planets on 10 au circular and eccentric orbits around a solar mass star. We find that this feedback reduces but does not halt the accretion on to the planet, although this result might depend on the near-coincident radial ranges where both recipes are implemented. Our simulations also show that the planet heating gives the accretion rate a stochastic variability with an amplitude $\Delta \dot{M}_p \sim 0.1 \dot{M}_p$ . A planet on an eccentric orbit (e = 0.1) presents a similar variability amplitude, but concentrated on a well-defined periodicity of half the orbital period and weaker broad-band noise, potentially allowing observations to discriminate between both cases. Finally, we find that the heating of the co-orbital region by the planet feedback alters the gas dynamics, reducing the difference between its orbital velocity and the Keplerian motion at the edge of the gap, which can have important consequences for the formation of dust rings.

Physical Review D(03/2021)doi:10.1103/PhysRevD.103.063013

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In very dense environments, neutrinos can undergo fast flavor conversions on scales as short as a few centimeters provided that the angular distribution of the neutrino lepton number crosses zero. This work presents the first attempt to establish whether the non-negligible abundance of muons and their interactions with neutrinos in the core of supernovae can affect the occurrence of such crossings. For this purpose we employ state-of-the-art one-dimensional core-collapse supernova simulations, considering models that include muon-neutrino interactions as well as models without these reactions. Although a consistent treatment of muons in the equation of state and neutrino transport does not seem to modify significantly the conditions for the occurrence of fast modes, it allows for the existence of an interesting phenomenon, namely fast instabilities in the μ -τ sector. We also show that crossings below the supernova shock are a relatively generic feature of the one-dimensional simulations under investigation, which contrasts with the previous reports in the literature. Our results highlight the importance of multidimensional simulations with muon creation, where our results must be tested in the future.

Monthly Notices of the Royal Astronomical Society(03/2021)doi:10.1093/mnras/stab089

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We analyse the near-infrared colour-magnitude diagram of a field including the giant molecular cloud G0.253+0.016 (a.k.a. The Brick) observed at high spatial resolution, with HAWK-I@VLT. The distribution of red clump stars in a line of sight crossing the cloud, compared with that in a direction just beside it, and not crossing it, allow us to measure the distance of the cloud from the Sun to be 7.20, with a statistical uncertainty of ±0.16 and a systematic error of ±0.20 kpc. This is significantly closer than what is generally assumed, i.e. that the cloud belongs to the near side of the central molecular zone, at 60 pc from the Galactic centre. This assumption was based on dynamical models of the central molecular zone, observationally constrained uniquely by the radial velocity of this and other clouds. Determining the true position of the Brick cloud is relevant because this is the densest cloud of the Galaxy not showing any ongoing star formation. This puts the cloud off by one order of magnitude from the Kennicutt-Schmidt relation between the density of the dense gas and the star formation rate. Several explanations have been proposed for this absence of star formation, most of them based on the dynamical evolution of this and other clouds, within the Galactic centre region. Our result emphasizes the need to include constraints coming from stellar observations in the interpretation of our Galaxy's central molecular zone.

MIAPbP

Physical Review D(03/2021)doi:10.1103/PhysRevD.103.054502

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We present the first determination of the hadronic decays of the lightest exotic J^{P C}=1^-+ resonance in lattice QCD. Working with SU(3) flavor symmetry, where the up, down and strange-quark masses approximately match the physical strange-quark mass giving m_π∼700 MeV , we compute finite-volume spectra on six lattice volumes which constrain a scattering system featuring eight coupled channels. Analytically continuing the scattering amplitudes into the complex-energy plane, we find a pole singularity corresponding to a narrow resonance which shows relatively weak coupling to the open pseudoscalar-pseudoscalar, vector-pseudoscalar and vector-vector decay channels, but large couplings to at least one kinematically closed axial-vector-pseudoscalar channel. Attempting a simple extrapolation of the couplings to physical light-quark mass suggests a broad π₁ resonance decaying dominantly through the b₁π mode with much smaller decays into f₁π , ρ π , η^′π and η π . A large total width is potentially in agreement with the experimental π₁(1564 ) candidate state observed in η π , η^′π , which we suggest may be heavily suppressed decay channels.

RU-C

The Astrophysical Journal(03/2021)doi:10.3847/1538-4357/abe387

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As cosmic structures form, matter density fluctuations collapse gravitationally and baryonic matter is shock-heated and thermalized. We therefore expect a connection between the mean gravitational potential energy density of collapsed halos, ${{\rm{\Omega }}}_{W}^{\mathrm{halo}}$ , and the mean thermal energy density of baryons, Ω_th. These quantities can be obtained using two fundamentally different estimates: we compute ${{\rm{\Omega }}}_{W}^{\mathrm{halo}}$ using the theoretical framework of the halo model, which is driven by dark matter statistics, and measure Ω_th using the Sunyaev-Zeldovich (SZ) effect, which probes the mean thermal pressure of baryons. First, we derive that, at the present time, about 90% of ${{\rm{\Omega }}}_{W}^{\mathrm{halo}}$ originates from massive halos with M > 10¹³ M_⊙. Then, using our measurements of the SZ background, we find that Ω_th accounts for about 80% of the kinetic energy of the baryons available for pressure in halos at z ≲ 0.5. This constrains the amount of nonthermal pressure, e.g., due to bulk and turbulent gas motion sourced by mass accretion, to be about Ω_non-th ≃ 0.4 × 10^-8 at z = 0.

Physical Review Research(03/2021)doi:10.1103/PhysRevResearch.3.013258

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Spatial organization of proteins in cells is important for many biological functions. In general, the nonlinear, spatially coupled models for protein-pattern formation are only accessible to numerical simulations, which has limited insight into the general underlying principles. To overcome this limitation, we adopt the setting of two diffusively coupled, well-mixed compartments that represents the elementary feature of any pattern—an interface. For intracellular systems, the total numbers of proteins are conserved on the relevant timescale of pattern formation. Thus the essential dynamics is the redistribution of the globally conserved mass densities between the two compartments. We present a phase-portrait analysis in the phase-space of the redistributed masses that provides insights on the physical mechanisms underlying pattern formation. We demonstrate this approach for several paradigmatic model systems. In particular, we show that the pole-to-pole Min oscillations in Escherichia coli are relaxation oscillations of the MinD polarity orientation. This reveals a close relation between cell polarity oscillatory patterns in cells. Critically, our findings suggest that the design principles of intracellular pattern formation are found in characteristic features in these phase portraits (nullclines and fixed points). These features are not uniquely determined by the topology of the protein-interaction network but depend on parameters (kinetic rates, diffusion constants) and distinct networks can give rise to equivalent phase portrait features.

CN-7

RU-A

The Astrophysical Journal(03/2021)doi:10.3847/1538-4357/abd54e

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The diffuse cosmic supernova neutrino background (DSNB) is an observational target of the gadolinium-loaded Super-Kamiokande (SK) detector and the forthcoming JUNO and Hyper-Kamiokande detectors. Current predictions are hampered by our still incomplete understanding of the supernova (SN) explosion mechanism and of the neutron star (NS) equation of state and maximum mass. In our comprehensive study we revisit this problem on grounds of the landscapes of successful and failed SN explosions obtained by Sukhbold et al. and Ertl et al. with parameterized one-dimensional neutrino engines for large sets of single-star and helium-star progenitors, with the latter serving as a proxy for binary evolution effects. Besides considering engines of different strengths, leading to different fractions of failed SNe with black hole (BH) formation, we also vary the NS mass limit and the spectral shape of the neutrino emission and include contributions from poorly understood alternative NS formation channels, such as accretion-induced and merger-induced collapse events. Since the neutrino signals of our large model sets are approximate, we calibrate the associated degrees of freedom by using state-of-the-art simulations of proto-NS cooling. Our predictions are higher than other recent ones because of a large fraction of failed SNe with long delay to BH formation. Our best-guess model predicts a DSNB ${\bar{\nu }}_{{\rm{e}}}$ <!-- --> -flux of ${28.8}_{-10.9}^{+24.6}$ <!-- --> cm^-2 s^-1 with ${6.0}_{-2.1}^{+5.1}$ <!-- --> cm^-2 s^-1 in the favorable measurement interval of [10, 30] MeV and ${1.3}_{-0.4}^{+1.1}$ <!-- --> cm^-2 s^-1 with ${\bar{\nu }}_{{\rm{e}}}$ <!-- --> energies > 17.3 MeV, which is roughly a factor of two below the current SK limit. The uncertainty range is dominated by the still insufficiently constrained cosmic rate of stellar core-collapse events.

CN-5

Monthly Notices of the Royal Astronomical Society(03/2021)doi:10.1093/mnras/staa3875

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We introduce the LYRA project, a new high-resolution galaxy formation model built within the framework of the cosmological hydrodynamical moving mesh code AREPO. The model resolves the multiphase interstellar medium (ISM) down to 10 K. It forms individual stars sampled from the initial mass function (IMF), and tracks their lifetimes and death pathways individually. Single supernova (SN) blast waves with variable energy are followed within the hydrodynamic calculation to interact with the surrounding ISM. In this paper, we present the methods and apply the model to a $10^{10}\, \mathrm{M}_{\odot }$ isolated halo. We demonstrate that the majority of SNe are Sedov resolved at our fiducial gas mass resolution of $4\, \mathrm{M}_{\odot }$ . We show that our SN feedback prescription self-consistently produces a hot phase within the ISM that drives significant outflows, reduces the gas density, and suppresses star formation. Clustered SNe play a major role in enhancing the effectiveness of feedback, because the majority of explosions occur in low-density material. Accounting for variable SN energy allows the feedback to respond directly to stellar evolution. We show that the ISM is sensitive to the spatially distributed energy deposition. It strongly affects the outflow behaviour, reducing the mass loading by a factor of 2-3, thus allowing the galaxy to retain a higher fraction of mass and metals. LYRA makes it possible to use a comprehensive multiphysics ISM model directly in cosmological (zoom) simulations of dwarf and higher mass galaxies.

RU-D

Astronomy and Astrophysics(03/2021)doi:10.1051/0004-6361/202039925

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Context. Pebble accretion is an emerging paradigm for the fast growth of planetary cores. Pebble flux and pebble sizes are the key parameters used in the pebble accretion models.
Aims: We aim to derive the pebble sizes and fluxes from state-of-the-art dust coagulation models and to understand their dependence on disk parameters and the fragmentation threshold velocity, and the impact of those on planetary growth by pebble accretion.
Methods: We used a 1D dust evolution model including dust growth and fragmentation to calculate realistic pebble sizes and mass flux. We used this information to integrate the growth of planetary embryos placed at various locations in the protoplanetary disk.
Results: Pebble flux strongly depends on disk properties including size and turbulence level, as well as the dust aggregates' fragmentation threshold. We find that dust fragmentation may be beneficial to planetary growth in multiple ways. First of all, it prevents the solids from growing to very large sizes, at which point the efficiency of pebble accretion drops. What is more, small pebbles are depleted at a lower rate, providing a long-lasting pebble flux. As the full coagulation models are computationally expensive, we provide a simple method of estimating pebble sizes and flux in any protoplanetary disk model without substructure and with any fragmentation threshold velocity.

Journal of Cosmology and Astroparticle Physics(03/2021)doi:10.1088/1475-7516/2021/03/051

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In first-order cosmological phase transitions, the asymptotic velocity of expanding bubbles is of crucial relevance for predicting observables like the spectrum of stochastic gravitational waves, or for establishing the viability of mechanisms explaining fundamental properties of the universe such as the observed baryon asymmetry. In these dynamic phase transitions, it is generally accepted that subluminal bubble expansion requires out-of-equilibrium interactions with the plasma which are captured by friction terms in the equations of motion for the scalar field. This has been disputed in works pointing out subluminal velocities in local equilibrium arising either from hydrodynamic effects in deflagrations or from the entropy change across the bubble wall in general situations. We argue that both effects are related and can be understood from the conservation of the entropy of the degrees of freedom in local equilibrium, leading to subluminal speeds for both deflagrations and detonations. The friction effect arises from the background field dependence of the entropy density in the plasma, and can be accounted for by simply imposing local conservation of stress-energy and including field dependent thermal contributions to the effective potential. We illustrate this with explicit calculations of dynamic and static bubbles for a first-order electroweak transition in a Standard Model extension with additional scalar fields.

Journal of Cosmology and Astroparticle Physics(03/2021)doi:10.1088/1475-7516/2021/03/054

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There is a guaranteed background of stochastic gravitational waves produced in the thermal plasma in the early universe. Its energy density per logarithmic frequency interval scales with the maximum temperature T_max which the primordial plasma attained at the beginning of the standard hot big bang era. It peaks in the microwave range, at around 80 GHz [106.75/g_*s(T_max)]^1/3, where g_*s(T_max) is the effective number of entropy degrees of freedom in the primordial plasma at T_max. We present a state-of-the-art prediction of this Cosmic Gravitational Microwave Background (CGMB) for general models, and carry out calculations for the case of the Standard Model (SM) as well as for several of its extensions. On the side of minimal extensions we consider the Neutrino Minimal SM (νMSM) and the SM-Axion-Seesaw-Higgs portal inflation model (SMASH), which provide a complete and consistent cosmological history including inflation. As an example of a non-minimal extension of the SM we consider the Minimal Supersymmetric Standard Model (MSSM). Furthermore, we discuss the current upper limits and the prospects to detect the CGMB in laboratory experiments and thus measure the maximum temperature and the effective number of degrees of freedom at the beginning of the hot big bang.

RU-D

The Astrophysical Journal(02/2021)doi:10.3847/1538-4357/abd24f

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We analyzed archival molecular line data of pre-main-sequence (PMS) stars in the Lupus and Taurus star-forming regions obtained with ALMA surveys with an integration time of a few minutes per source. We stacked the data of ¹³CO and C¹⁸O (J = 2-1 and 3-2) and CN (N = 3-2, J = 7/2-5/2) lines to enhance the signal-to-noise ratios and measured the stellar masses of 45 out of 67 PMS stars from the Keplerian rotation in their circ*mstellar disks. The measured dynamical stellar masses were compared to the stellar masses estimated from the spectroscopic measurements with seven different stellar evolutionary models. We found that the magnetic model of Feiden provides the best estimate of the stellar masses in the mass range of 0.6 M_⊙ ≤ M_⋆ ≤ 1.3 M_⊙ with a deviation of <0.7σ from the dynamical masses, while all the other models underestimate the stellar masses in this mass range by 20%-40%. In the mass range of <0.6 M_⊙, the stellar masses estimated with the magnetic model of Feiden have a larger deviation (>2σ) from the dynamical masses, and other, nonmagnetic stellar evolutionary models of Siess et al., Baraffe et al., and Feiden show better agreement with the dynamical masses with the deviations of 1.4σ-1.6σ. Our results show the mass dependence of the accuracy of these stellar evolutionary models.

(02/2021)e-Print:2102.05601

abstract +abstract -

The apparent clustering in longitude of perihelion $\varpi$ and ascending node $\Omega$ of extreme trans-Neptunian objects (ETNOs) has been attributed to the gravitational effects of an unseen 5-10 Earth-mass planet in the outer solar system. To investigate how selection bias may contribute to this clustering, we consider 14 ETNOs discovered by the Dark Energy Survey, the Outer Solar System Origins Survey, and the survey of Sheppard and Trujillo. Using each survey's published pointing history, depth, and TNO tracking selections, we calculate the joint probability that these objects are consistent with an underlying parent population with uniform distributions in $\varpi$ and $\Omega$. We find that the mean scaled longitude of perihelion and orbital poles of the detected ETNOs are consistent with a uniform population at a level between $17\%$ and $94\%$, and thus conclude that this sample provides no evidence for angular clustering.

Astrophys.J.Supp.(02/2021)e-Print:2102.05033doi:10.3847/1538-4365/ac35e9

abstract +abstract -

We present component-separated maps of the primary cosmic microwave background/kinematic Sunyaev–Zel’dovich (SZ) amplitude and the thermal SZ Compton-y parameter, created using data from the South Pole Telescope (SPT) and the Planck satellite. These maps, which cover the ∼2500 deg$^{2}$ of the southern sky imaged by the SPT-SZ survey, represent a significant improvement over previous such products available in this region by virtue of their higher angular resolution ( for our highest-resolution Compton-y maps) and lower noise at small angular scales. In this work we detail the construction of these maps using linear combination techniques, including our method for limiting the correlation of our lowest-noise Compton-y map products with the cosmic infrared background. We perform a range of validation tests on these data products to test our sky modeling and combination algorithms, and we find good performance in all of these tests. Recognizing the potential utility of these data products for a wide range of astrophysical and cosmological analyses, including studies of the gas properties of galaxies, groups, and clusters, we make these products publicly available at pole.uchicago.edu/public/data/sptsz_ymap and on the NASA/LAMBDA website.

MIAPbP

Physical Review D(02/2021)doi:10.1103/PhysRevD.103.034505

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Nonzero topological charge is prohibited in the chiral limit of continuum gauge-fermion systems because any unpaired instanton would create a zero mode of the Dirac operator. On the lattice, however, the geometric Q_geom=⟨F F ∼ ⟩/32 π² definition of the topological charge does not necessarily vanish in the chiral limit even when the gauge fields are smoothed for example with gradient flow. Small vacuum fluctuations (dislocations) not seen by the fermions may be promoted to instantonlike objects by the gradient flow. We demonstrate that these artifacts of the flow cause the gradient flow renormalized gauge coupling to increase and appear to run faster. In step-scaling studies such strong coupling artifacts contribute a term that might not follow perturbative scaling. The usual a /L →0 continuum limit extrapolations can hence lead to incorrect results. In this paper we investigate these topological lattice artifacts in the massless SU(3) 10-flavor system with domain wall fermions and the massless 8-flavor system with staggered fermions. For both systems we observe that in the range of strong coupling Symanzik gradient flow exhibits more lattice artifacts compared to Wilson gradient flow. We demonstrate how this artifact impacts the determination of the renormalized gauge coupling and the step-scaling β function.

CN-7

Physics Letters B(02/2021)doi:10.1016/j.physletb.2020.136016

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In the past two decades, pions created in the high density regions of heavy ion collisions have been predicted to be sensitive at high densities to the symmetry energy term in the nuclear equation of state, a property that is key to our understanding of neutron stars. In a new experiment designed to study the symmetry energy, the multiplicities of negatively and positively charged pions have been measured with high accuracy for central ¹³²Sn+¹²⁴Sn, ¹¹²Sn+¹²⁴Sn, and ¹⁰⁸Sn+¹¹²Sn collisions at E / A = 270 MeV with the SπRIT Time Projection Chamber. While individual pion multiplicities are measured to 4% accuracy, those of the charged pion multiplicity ratios are measured to 2% accuracy. We compare these data to predictions from seven major transport models. The calculations reproduce qualitatively the dependence of the multiplicities and their ratios on the total neutron and proton number in the colliding systems. However, the predictions of the transport models from different codes differ too much to allow extraction of reliable constraints on the symmetry energy from the data. This finding may explain previous contradictory conclusions on symmetry energy constraints obtained from pion data in Au+Au system. These new results call for still better understanding of the differences among transport codes, and new observables that are more sensitive to the density dependence of the symmetry energy.

MIAPbP

Journal of Cosmology and Astroparticle Physics(02/2021)doi:10.1088/1475-7516/2021/02/046

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In this paper we analyze the spectrum of the primordial gravitational waves (GWs) predicted in the Standard Model*Axion*Seesaw*Higgs portal inflation (SMASH) model, which was proposed as a minimal extension of the Standard Model that addresses five fundamental problems of particle physics and cosmology (inflation, baryon asymmetry, neutrino masses, strong CP problem, and dark matter) in one stroke. The SMASH model has a unique prediction for the critical temperature of the second order Peccei-Quinn (PQ) phase transition T_c ~ 10⁸ GeV up to the uncertainty in the calculation of the axion dark matter abundance, implying that there is a drastic change in the equation of state of the universe at that temperature. Such an event is imprinted on the spectrum of GWs originating from the primordial tensor fluctuations during inflation and entering the horizon at T ~ T_c, which corresponds to f ~ 1 Hz, pointing to a best frequency range covered by future space-borne GW interferometers. We give a precise estimation of the effective relativistic degrees of freedom across the PQ phase transition and use it to evaluate the spectrum of GWs observed today. It is shown that the future high sensitivity GW experiment—ultimate DECIGO—can probe the nontrivial feature resulting from the PQ phase transition in this model.

CN-4

RU-C

Physical Review D(02/2021)doi:10.1103/PhysRevD.103.043502

abstract +abstract -

We investigate the application of volume statistics to probe the distribution of underdense regions in the large-scale structure of the Universe. This statistic measures the distortion of Eulerian volume elements relative to Lagrangian ones and can be built from tracer particles using tessellation methods. We apply Voronoi and Delaunay tessellation to study the clustering properties of density and volume statistics. Their level of shot-noise contamination is similar, as both methods take into account all available tracer particles in the field estimator. The tessellation causes a smoothing effect in the power spectrum, which can be approximated by a constant window function on large scales. The clustering bias of the volume statistic with respect to the dark matter density field is determined and found to be negative. We further identify the baryon acoustic oscillation (BAO) feature in the volume statistic. Apart from being smoothed out on small scales, the BAO is present in the volume power spectrum as well, without any systematic bias. These observations suggest that the exploitation of volume statistics as a complementary probe of cosmology is very promising.

Astronomy and Astrophysics(02/2021)doi:10.1051/0004-6361/202039218

abstract +abstract -

To use strongly lensed Type Ia supernovae (LSNe Ia) for cosmology, a time-delay measurement between the multiple supernova (SN) images is necessary. The sharp rise and decline of SN Ia light curves make them promising for measuring time delays, but microlensing can distort these light curves and therefore add large uncertainties to the measurements. An alternative approach is to use color curves where uncertainties due to microlensing are significantly reduced for a certain period of time known as the achromatic phase. In this work, we investigate in detail the achromatic phase, testing four different SN Ia models with various microlensing configurations. We find on average an achromatic phase of around three rest-frame weeks or longer for most color curves, but the spread in the duration of the achromatic phase (due to different microlensing maps and filter combinations) is quite large and an achromatic phase of just a few days is also possible. Furthermore, the achromatic phase is longer for smoother microlensing maps and lower macro-magnifications. From our investigations, we do not find a strong dependency on the SN model or on asymmetries in the SN ejecta. We find that six rest-frame LSST color curves exhibit features such as extreme points or turning points within the achromatic phase, which make them promising for time-delay measurements; however, only three of the color curves are independent. These curves contain combinations of rest-frame bands u, g, r, and i, and to observe them for typical LSN Ia redshifts, it would be ideal to cover (observer-frame) filters r, i, z, y, J, and H. If follow-up resources are restricted, we recommend r, i, and z as the bare minimum for using color curves and/or light curves since LSNe Ia are bright in these filters and observational uncertainties are lower than in the infrared regime. With additional resources, infrared observations in y, J, and H would be useful for obtaining color curves of SNe, especially at redshifts above ∼0.8 when they become critical.

RU-D

The Astrophysical Journal(02/2021)doi:10.3847/2041-8213/abdf57

abstract +abstract -

Gas-rich circ*mstellar disks are the cradles of planet formation. As such, their evolution will strongly influence the resulting planet population. In the ESO DESTINYS large program, we study these disks within the first 10 Myr of their development with near-infrared scattered-light imaging. Here we present VLT/SPHERE polarimetric observations of the nearby class II system SU Aur in which we resolve the disk down to scales of ∼7 au. In addition to the new SPHERE observations, we utilize VLT/NACO, HST/STIS, and ALMA archival data. The new SPHERE data show the disk around SU Aur and extended dust structures in unprecedented detail. We resolve several dust tails connected to the Keplerian disk. By comparison with ALMA data, we show that these dust tails represent material falling onto the disk. The disk itself shows an intricate spiral structure and a shadow lane, cast by an inner, misaligned disk component. Our observations suggest that SU Aur is undergoing late infall of material, which can explain the observed disk structures. SU Aur is the clearest observational example of this mechanism at work and demonstrates that late accretion events can still occur in the class II phase, thereby significantly affecting the evolution of circ*mstellar disks. Constraining the frequency of such events with additional observations will help determine whether this process is responsible for the spin-orbit misalignment in evolved exoplanet systems. * Based on observations performed with VLT/SPHERE under program ID 1104.C-0415(E).

Physical Review Letters(02/2021)doi:10.1103/PhysRevLett.126.082003

abstract +abstract -

We compute the color-singlet and color-octet nonrelativistic QCD (NRQCD) long-distance matrix elements for inclusive production of P -wave quarkonia in the framework of potential NRQCD. In this way, the color-octet NRQCD long-distance matrix element can be determined without relying on measured cross section data, which has not been possible so far. We obtain inclusive cross sections of χ_{c J} and χ_{b J} at the LHC, which are in good agreement with data. In principle, the formalism developed in this Letter can be applied to all inclusive production processes of heavy quarkonia.

Monthly Notices of the Royal Astronomical Society(02/2021)doi:10.1093/mnras/staa3772

abstract +abstract -

Dark matter models involving a very light bosonic particle, generally known as fuzzy dark matter (FDM), have been recently attracting great interest in the cosmology community, as their wave-like phenomenology would simultaneously explain the long-standing misdetection of a dark matter particle and help easing the small-scale issues related to the standard cold dark matter (CDM) scenario. With this work, we initiate a series of papers aiming at investigating the evolution of FDM structures in a cosmological framework performed with our N-body code AX-GADGET, detailing for the first time in the literature how the actual scaling relations between solitonic cores and host haloes properties are significantly affected by the dynamical state, morphology, and merger history of the individual systems. In particular, in this first paper we confirm the ability of AX-GADGET to correctly reproduce the typical FDM solitonic core and we employ it to study the non-linear evolution of eight FDM haloes in their cosmological context through the zoom-in simulation approach. We find that the scaling relations identified in previous works for isolated systems are generally modified for haloes evolving in a realistic cosmological environment, and appear to be valid only as a limit for the most relaxed and spherically symmetric systems.

MIAPbP

Chinese Physics C(02/2021)doi:10.1088/1674-1137/abcd8e

abstract +abstract -

Hexaquarks constitute a natural extension of complex quark systems, just as tetra- and pentaquarks do. To this end, the current status of $d^*(2380)$ in both experiment and theory is reviewed. Recent high-precision measurements in the nucleon-nucleon channel and analyses thereof have established $d^*(2380)$ as an indisputable resonance in the long-sought dibaryon channel. Important features of this $I(J^P) = 0(3^+)$ state are its narrow width and deep binding relative to the $\Delta(1232)\Delta(1232)$ threshold. Its decay branchings favor theoretical calculations predicting a compact hexaquark nature of this state. We review the current status of experimental and theoretical studies on $d^*(2380)$ as well as new physics aspects it may bring in future. In addition, we review the situation at the $\Delta(1232) N$ and $N^*(1440)N$ thresholds, where evidence for a number of resonances of presumably molecular nature has been found - similar to the situation in charmed and beauty sectors. Finally, we briefly discuss the situation of dibaryon searches in the flavored quark sectors. * This work has been supported by DFG (CL 214/3-3). H. Cl. appreciates the support by the Munich Institute for Astro- and Particle Physics (MIAPP) which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy - EXC-2094 - 390783311

CN-2

RU-D

Astronomy and Astrophysics(02/2021)doi:10.1051/0004-6361/202039658

abstract +abstract -

Context. Transition discs are expected to be a natural outcome of the interplay between photoevaporation and giant planet formation. Massive planets reduce the inflow of material from the outer to the inner disc, therefore triggering an earlier onset of disc dispersal due to photoevaporation through a process known as Planet-Induced PhotoEvaporation. In this case, a cavity is formed as material inside the planetary orbit is removed by photoevaporation, leaving only the outer disc to drive the migration of the giant planet.
Aims: We investigate the impact of photoevaporation on giant planet migration and focus specifically on the case of transition discs with an evacuated cavity inside the planet location. This is important for determining under what circ*mstances photoevaporation is efficient at halting the migration of giant planets, thus affecting the final orbital distribution of a population of planets.
Methods: For this purpose, we use 2D FARGO simulations to model the migration of giant planets in a range of primordial and transition discs subject to photoevaporation. The results are then compared to the standard prescriptions used to calculate the migration tracks of planets in 1D planet population synthesis models.
Results: The FARGO simulations show that once the disc inside the planet location is depleted of gas, planet migration ceases. This contradicts the results obtained by the impulse approximation, which predicts the accelerated inward migration of planets in discs that have been cleared inside the planetary orbit.
Conclusions: These results suggest that the impulse approximation may not be suitable for planets embedded in transition discs. A better approximation that could be used in 1D models would involve halting planet migration once the material inside the planetary orbit is depleted of gas and the surface density at the 3:2 mean motion resonance location in the outer disc reaches a threshold value of 0.01 g cm⁻².

Physical Review C(02/2021)doi:10.1103/PhysRevC.103.025806

abstract +abstract -

Neutron star (NS) merger ejecta offer viable sites for the production of heavy r -process elements with nuclear mass numbers A ≳140 . The crucial role of fission recycling is responsible for the robustness of this site against many astrophysical uncertainties. Here, we introduce improvements to our scission-point model, called SPY, to derive the fission fragment distribution for all neutron-rich fissioning nuclei of relevance in r -process calculations. These improvements include a phenomenological modification of the scission distance and a smoothing procedure of the distribution. Such corrections lead to much better agreement with experimental fission yields. Those yields are also used to estimate the number of neutrons emitted by the excited fragments on the basis of different neutron evaporation models. Our fission yields are extensively compared to those predicted by the GEF (general description of fission observables) model. The impact of fission on the r -process nucleosynthesis in binary neutron mergers is also reanalyzed. Two scenarios are considered, the first one with low initial electron fraction subject to intense fission recycling, in contrast to the second one, which includes weak interactions on nucleons. The various regions of the nuclear chart responsible for fission recycling during the neutron irradiation and after freeze-out are discussed. The contribution fission processes may have to the final abundance distribution is also studied in detail in the light of newly defined quantitative indicators describing the fission recycling, the fission seeds, and the fission progenitors. In particular, those allow us to estimate the contribution of fission to the final abundance distribution stemming from specific heavy nuclei. Calculations obtained with SPY and GEF fission fragment distributions are compared for both r -process scenarios.

Astronomy and Astrophysics(02/2021)doi:10.1051/0004-6361/202039574

abstract +abstract -

Modeling the mass distributions of strong gravitational lenses is often necessary in order to use them as astrophysical and cosmological probes. With the large number of lens systems (≳10⁵) expected from upcoming surveys, it is timely to explore efficient modeling approaches beyond traditional Markov chain Monte Carlo techniques that are time consuming. We train a convolutional neural network (CNN) on images of galaxy-scale lens systems to predict the five parameters of the singular isothermal ellipsoid (SIE) mass model (lens center x and y, complex ellipticity e_x and e_y, and Einstein radius θ_E). To train the network we simulate images based on real observations from the Hyper Suprime-Cam Survey for the lens galaxies and from the Hubble Ultra Deep Field as lensed galaxies. We tested different network architectures and the effect of different data sets, such as using only double or quad systems defined based on the source center and using different input distributions of θ_E. We find that the CNN performs well, and with the network trained on both doubles and quads with a uniform distribution of θ_E > 0.5″ we obtain the following median values with 1σ scatter: Δx = (0.00_-0.30^+0.30)″, Δy = (0.00_-0.29^+0.30)″, Δθ_E = (0.07_-0.12^+0.29)″, Δe_x = -0.01_-0.09^+0.08, and Δe_y = 0.00_-0.09^+0.08. The bias in θ_E is driven by systems with small θ_E. Therefore, when we further predict the multiple lensed image positions and time-delays based on the network output, we apply the network to the sample limited to θ_E > 0.8″. In this case the offset between the predicted and input lensed image positions is (0.00_-0.29^+0.29)″ and (0.00_-0.31^+0.32)″ for the x and y coordinates, respectively. For the fractional difference between the predicted and true time-delay, we obtain 0.04_-0.05^+0.27. Our CNN model is able to predict the SIE parameter values in fractions of a second on a single CPU, and with the output we can predict the image positions and time-delays in an automated way, such that we are able to process efficiently the huge amount of expected galaxy-scale lens detections in the near future.

The Astrophysical Journal(02/2021)doi:10.3847/1538-4357/abd183

abstract +abstract -

We performed the largest and most hom*ogeneous spectroscopic survey of field RR Lyraes (RRLs). We secured ≍6300 high-resolution (HR, R ∼ 35,000) spectra for 143 RRLs (111 fundamental, RRab; 32 first-overtone, RRc). The atmospheric parameters were estimated by using the traditional approach and the iron abundances were measured by using an LTE line analysis. The resulting iron distribution shows a well-defined metal-rich tail approaching solar iron abundance. This suggests that field RRLs experienced a complex chemical enrichment in the early halo formation. We used these data to develop a new calibration of the ΔS method. This diagnostic, based on the equivalent widths of Ca II K and three Balmer (H_δ,γ,β) lines, traces the metallicity of RRLs. For the first time, the new empirical calibration: (i) includes spectra collected over the entire pulsation cycle; (ii) includes RRc variables; (iii) relies on spectroscopic calibrators covering more than three dex in iron abundance; and (iv) provides independent calibrations based on one/two/three Balmer lines. The new calibrations were applied to a data set of both SEGUE-SDSS and degraded HR spectra totalling 6451 low-resolution (R ∼ 2000) spectra for 5001 RRLs (3439 RRab, 1562 RRc). This resulted in an iron distribution with a median η = -1.55 ± 0.01 and σ = 0.51 dex, in good agreement with literature values. We also found that RRc are 0.10 dex more metal-poor than RRab variables, and have a distribution with a smoother metal-poor tail. This finding supports theoretical prescriptions suggesting a steady decrease in the RRc number when moving from metal-poor to metal-rich stellar environments. ^* Based on observations obtained with the du Pont telescope at Las Campanas Observatory, operated by Carnegie Institution for Science. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Based partly on data obtained with the STELLA robotic telescopes in Tenerife, an AIP facility jointly operated by AIP and IAC. Some of the observations reported in this paper were obtained with the Southern African Large Telescope (SALT). Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Fundación Galileo Galilei of the INAF (Istituto Nazionale di Astrofisica) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere.

Astronomy and Astrophysics(02/2021)doi:10.1051/0004-6361/202038831

abstract +abstract -

We present the methodology for a joint cosmological analysis of weak gravitational lensing from the fourth data release of the ESO Kilo-Degree Survey (KiDS-1000) and galaxy clustering from the partially overlapping Baryon Oscillation Spectroscopic Survey (BOSS) and the 2-degree Field Lensing Survey (2dFLenS). Cross-correlations between BOSS and 2dFLenS galaxy positions and source galaxy ellipticities have been incorporated into the analysis, necessitating the development of a hybrid model of non-linear scales that blends perturbative and non-perturbative approaches, and an assessment of signal contributions by astrophysical effects. All weak lensing signals were measured consistently via Fourier-space statistics that are insensitive to the survey mask and display low levels of mode mixing. The calibration of photometric redshift distributions and multiplicative gravitational shear bias has been updated, and a more complete tally of residual calibration uncertainties was propagated into the likelihood. A dedicated suite of more than 20 000 mocks was used to assess the performance of covariance models and to quantify the impact of survey geometry and spatial variations of survey depth on signals and their errors. The sampling distributions for the likelihood and the χ² goodness-of-fit statistic have been validated, with proposed changes for calculating the effective number of degrees of freedom. The prior volume was explicitly mapped, and a more conservative, wide top-hat prior on the key structure growth parameter S₈ = σ₈ (Ω_m/0.3)^1/2 was introduced. The prevalent custom of reporting S₈ weak lensing constraints via point estimates derived from its marginal posterior is highlighted to be easily misinterpreted as yielding systematically low values of S₈, and an alternative estimator and associated credible interval are proposed. Known systematic effects pertaining to weak lensing modelling and inference are shown to bias S₈ by no more than 0.1 standard deviations, with the caveat that no conclusive validation data exist for models of intrinsic galaxy alignments. Compared to the previous KiDS analyses, S₈ constraints are expected to improve by 20% for weak lensing alone and by 29% for the joint analysis.

MIAPbP

Journal of High Energy Physics(02/2021)doi:10.1007/JHEP02(2021)029

abstract +abstract -

We transform the metric of an isolated matter source in the multipolar post-Minkowskian approximation from harmonic (de Donder) coordinates to radiative Newman-Unti (NU) coordinates. To linearized order, we obtain the NU metric as a functional of the mass and current multipole moments of the source, valid all-over the exterior region of the source. Imposing appropriate boundary conditions we recover the generalized Bondi-van der Burg-Metzner-Sachs residual symmetry group. To quadratic order, in the case of the mass-quadrupole interaction, we determine the contributions of gravitational-wave tails in the NU metric, and prove that the expansion of the metric in terms of the radius is regular to all orders. The mass and angular momentum aspects, as well as the Bondi shear, are read off from the metric. They are given by the radiative quadrupole moment including the tail terms.

CN-3

RU-B

Physical Review D(02/2021)doi:10.1103/PhysRevD.103.035010

abstract +abstract -

Two-loop effects on the right-handed neutrino masses can have an impact on the low-energy phenomenology, especially when the right-handed neutrino mass spectrum is very hierarchical at the cutoff scale. In this case, the physical masses of the lighter right-handed neutrinos can be dominated by quantum effects induced by the heavier ones. Further, if the heaviest right-handed neutrino mass is at around the Planck scale, two-loop effects on the right-handed neutrino masses generate, through the seesaw mechanism, an active neutrino mass that is in the ballpark of the experimental values. In this paper we investigate extensions of the Planck-scale lepton number breaking scenario by additional Higgs doublets (inert or not). We find that under reasonable assumptions these models lead simultaneously to an overall neutrino mass scale and to a neutrino mass hierarchy in qualitative agreement with observations.

RU-A

Journal of High Energy Physics(02/2021)e-Print:2011.09813doi:10.1007/JHEP02%282021%29088

abstract +abstract -

CN-2

RU-D

RU-E

Astronomy and Astrophysics(01/2021)doi:10.1051/0004-6361/202039483

abstract +abstract -

We present an overview of the ALMA chemical survey of disk-outflow sources in Taurus (ALMA-DOT), a campaign devoted to the characterization of the molecular emission from partly embedded young stars. The project is aimed at attaining a better understanding of the gaseous products delivered to planets by means of high-resolution maps of the assorted lines probing disks at the time of planet formation (≲1 Myr). Nine different molecules are surveyed through our observations of six Class I/flat-spectrum sources. As part of a series of articles analyzing specific targets and molecules, in this work we describe the sample and provide a general overview of the results, focusing specifically on the spatial distribution, column densities, and abundance ratios of H₂CO, CS, and CN. In these embedded sources, the ¹²CO emission is dominated by envelope and outflow emission while the CS and, especially, the H₂CO are good tracers of the gaseous disk structure. The spatial distribution and brightness of the o-H₂CO 3_1,2-2_1,1 and CS 5-4 lines are very similar to each other and across all targets. The CN 2-1 line emission is fainter and distributed over radii larger than the dust continuum. The H₂CO and CS emission is always dimmed in the inner ~50 au. While the suppression by the dusty disk and absorption by the line-of-sight material significantly contributes to this inner depression, an actual decrease in the column density is plausible in most cases, making the observed ring-like morphology realistic. We also found that the gaseous disk extent, when traced by H₂CO (150-390 au), is always 60% larger than the dust disk. This systematic discrepancy may, in principle, be explained by the different optical depth of continuum and line emission without invoking any dust radial drift. Finally, the o-H₂CS 7_1,6-6_1,5 and CH₃OH 5_0,5-4_0,4 line emission are detected in two disks and one disk, respectively, while the HDO is never detected. The H₂CO column densities are 12-50 times larger than those inferred for Class II sources while they are in line with those of other Class 0/I. The CS column densities are lower than those of H₂CO, which is an opposite trend with regard to Class II objects. We also inferred abundance ratios between the various molecular species finding, among others, a H₂CS/H₂CO ratio that is systematically lower than unity (0.4-0.7 in HL Tau, 0.1 - 0.2 in IRAS 04302+2247, and <0.4 in all other sources), as well as a CH₃OH/H₂CO ratio (<0.7 in HL Tau and 0.5-0.7 in IRAS 04302+2247) that is lower than the only available estimate in a protoplanetary disks (1.3 in TW Hya) and between one and two orders of magnitude lower than those of the hot corinos around Class 0 protostars. These results are a first step toward the characterization of the disk's chemical evolution, which ought to be complemented by subsequent observations of less exceptional disks and customized thermo-chemical modeling.

CN-7

RU-A

Physical Review Letters(01/2021)e-Print:2012.13802 doi:10.1103/PhysRevLett.126.032502

abstract +abstract -

The mean-square charge radii of 207,208Hg (Z=80, N=127, 128) have been studied for the first time and those of 202,203,206Hg (N=122, 123, 126) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic kink in the charge radii at the N=126 neutron shell closure has been revealed, providing the first information on its behavior below the Z=82 proton shell closure. A theoretical analysis has been performed within relativistic Hartree-Bogoliubov and nonrelativistic Hartree-Fock-Bogoliubov approaches, considering both the new mercury results and existing lead data. Contrary to previous interpretations, it is demonstrated that both the kink at N=126 and the odd-even staggering (OES) in its vicinity can be described predominately at the mean-field level and that pairing does not need to play a crucial role in their origin. A new OES mechanism is suggested, related to the staggering in the occupation of the different neutron orbitals in odd- and even-A nuclei, facilitated by particle-vibration coupling for odd-A nuclei.

CN-3

PhD Thesis

Thesis(01/2021)doi:10.5282/edoc.27802

abstract +abstract -

While most galaxies evolve gradually, a subset of galaxies, such as star-forming galaxies falling into galaxy cluster or post-starburst galaxies (PSBs), evolve far more quickly. These transition galaxies are characterised by a short timescale decrease of star formation and offer key insights into how and by what mechanisms galaxies evolve. To resolve the extensive range of relevant physical processes involved in galaxy evolution, we analyse the state-of-the-art cosmological hydrodynamical simulation suite Magneticum Pathfinder. We track the orbits, merger history, galactic properties, and black holes of transition galaxies and control samples in different environments over several ∼ Gyr.

CN-8

PhD Thesis

abstract +abstract -

Understanding how systems that can replicate information can emerge from the interaction of informational polymers (DNA, RNA) is crucial to comprehend the origins of life on Earth. To this end, system-level properties arising from the interaction of informational polymers must be identified and understood. We abstract and coarse-grain the interaction details to find universal rules governing systems of self-assembly of informational polymers via templated ligation.

CN-4

RU-C

Mon.Not.Roy.Astron.Soc.(01/2021)e-Print:2101.04984doi:10.1093/mnras/stab869

abstract +abstract -

We perform a cross validation of the cluster catalogue selected by the red-sequence Matched-filter Probabilistic Percolation algorithm (redMaPPer) in Dark Energy Survey year 1 (DES-Y1) data by matching it with the Sunyaev–Zel’dovich effect (SZE) selected cluster catalogue from the South Pole Telescope SPT-SZ survey. Of the 1005 redMaPPer selected clusters with measured richness |$\hat{\lambda }\gt 40$| in the joint footprint, 207 are confirmed by SPT-SZ. Using the mass information from the SZE signal, we calibrate the richness–mass relation using a Bayesian cluster population model. We find a mass trend λ∝ M^B consistent with a linear relation (B ∼ 1), no significant redshift evolution and an intrinsic scatter in richness of σ_λ= 0.22±0.06. By considering two error models, we explore the impact of projection effects on the richness–mass modelling, confirming that such effects are not detectable at the current level of systematic uncertainties. At low richness SPT-SZ confirms fewer redMaPPer clusters than expected. We interpret this richness dependent deficit in confirmed systems as due to the increased presence at low richness of low-mass objects not correctly accounted for by our richness-mass scatter model, which we call contaminants. At a richness |$\hat{\lambda }=40$|⁠, this population makes up |${\gt}12{{\ \rm per\ cent}}$| (97.5 percentile) of the total population. Extrapolating this to a measured richness |$\hat{\lambda }=20$| yields |${\gt}22{{\ \rm per\ cent}}$| (97.5 percentile). With these contamination fractions, the predicted redMaPPer number counts in different plausible cosmologies are compatible with the measured abundance. The presence of such a population is also a plausible explanation for the different mass trends (B ∼ 0.75) obtained from mass calibration using purely optically selected clusters. The mean mass from stacked weak lensing (WL) measurements suggests that these low-mass contaminants are galaxy groups with masses ∼3–5×10^13 M_⊙ which are beyond the sensitivity of current SZE and X-ray surveys but a natural target for SPT-3G and eROSITA.

RU-C

Mon.Not.Roy.Astron.Soc.(01/2021)e-Print:2101.02257doi:10.1093/mnras/staa3936

abstract +abstract -

The COnstrain Dark Energy with X-ray clusters (CODEX) sample contains the largest flux limited sample of X-ray clusters at $0.35 < z < 0.65$. It was selected from ROSAT data in the 10,000 square degrees of overlap with BOSS, mapping a total number of 2770 high-z galaxy clusters. We present here the full results of the CFHT CODEX program on cluster mass measurement, including a reanalysis of CFHTLS Wide data, with 25 individual lensing-constrained cluster masses. We employ $lensfit$ shape measurement and perform a conservative colour-space selection and weighting of background galaxies. Using the combination of shape noise and an analytic covariance for intrinsic variations of cluster profiles at fixed mass due to large scale structure, miscentring, and variations in concentration and ellipticity, we determine the likelihood of the observed shear signal as a function of true mass for each cluster. We combine 25 individual cluster mass likelihoods in a Bayesian hierarchical scheme with the inclusion of optical and X-ray selection functions to derive constraints on the slope $\alpha$, normalization $\beta$, and scatter $\sigma_{\ln \lambda | \mu}$ of our richness-mass scaling relation model in log-space: $\left<\ln \lambda | \mu \right> = \alpha \mu + \beta$, with $\mu = \ln (M_{200c}/M_{\mathrm{piv}})$, and $M_{\mathrm{piv}} = 10^{14.81} M_{\odot}$. We find a slope $\alpha = 0.49^{+0.20}_{-0.15}$, normalization $ \exp(\beta) = 84.0^{+9.2}_{-14.8}$ and $\sigma_{\ln \lambda | \mu} = 0.17^{+0.13}_{-0.09}$ using CFHT richness estimates. In comparison to other weak lensing richness-mass relations, we find the normalization of the richness statistically agreeing with the normalization of other scaling relations from a broad redshift range ($0.0<z<0.65$) and with different cluster selection (X-ray, Sunyaev-Zeldovich, and optical).

MIAPbP

European Physical Journal C(01/2021)doi:10.1140/epjc/s10052-021-08853-y

abstract +abstract -

We discuss a method that employs a multilayer perceptron to detect deviations from a reference model in large multivariate datasets. Our data analysis strategy does not rely on any prior assumption on the nature of the deviation. It is designed to be sensitive to small discrepancies that arise in datasets dominated by the reference model. The main conceptual building blocks were introduced in D'Agnolo and Wulzer (Phys Rev D 99 (1), 015014. doi.org/10.1103/PhysRevD.99.015014. arXiv:1806.02350 [hep-ph], 2019). Here we make decisive progress in the algorithm implementation and we demonstrate its applicability to problems in high energy physics. We show that the method is sensitive to putative new physics signals in di-muon final states at the LHC. We also compare our performances on toy problems with the ones of alternative methods proposed in the literature.

RU-C

Journal of Cosmology and Astroparticle Physics(01/2021)doi:10.1088/1475-7516/2021/01/012

abstract +abstract -

We investigate the possibility of measuring the primordial gravitational wave (GW) signal across 21 decades in frequencies, using the cosmic microwave background (CMB), pulsar timing arrays (PTA), and laser and atomic interferometers. For the CMB and PTA experiments we consider the LiteBIRD mission and the Square Kilometer Array (SKA), respectively. For the interferometers we consider space mission proposals including the Laser Interferometer Space Antenna (LISA), the Big Bang Observer (BBO), the Deci-hertz Interferometer Gravitational wave Observatory (DECIGO), the μAres experiment, the Decihertz Observatory (DO), and the Atomic Experiment for Dark Matter and Gravity Exploration in Space (AEDGE), as well as the ground-based Einstein Telescope (ET) proposal. We implement the mathematics needed to compute sensitivities for both CMB and interferometers, and derive the response functions for the latter from the first principles. We also evaluate the effect of the astrophysical foreground contamination in each experiment. We present binned sensitivity curves and error bars on the energy density parameter, Ω_GWh², as a function of frequency for two representative classes of models for the stochastic background of primordial GW: the quantum vacuum fluctuation in the metric from single-field slow-roll inflation, and the source-induced tensor perturbation from the spectator axion-SU(2) inflation models. We find excellent prospects for joint measurements of the GW spectrum by CMB and space-borne interferometers mission proposals.

Monthly Notices of the Royal Astronomical Society(01/2021)doi:10.1093/mnras/staa3234

abstract +abstract -

We measure the anisotropic clustering of the quasar sample from Data Release 16 (DR16) of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey (eBOSS). A sample of 343 708 spectroscopically confirmed quasars between redshift 0.8 < z < 2.2 are used as tracers of the underlying dark matter field. In comparison with DR14 sample, the final sample doubles the number of objects as well as the survey area. In this paper, we present the analysis in configuration space by measuring the two-point correlation function and decomposing it using the Legendre polynomials. For the full-shape analysis of the Legendre multipole moments, we measure the baryon acoustic oscillation (BAO) distance and the growth rate of the cosmic structure. At an effective redshift of z_eff = 1.48, we measure the comoving angular diameter distance D_M(z_eff)/r_drag = 30.66 ± 0.88, the Hubble distance D_H(z_eff)/r_drag = 13.11 ± 0.52, and the product of the linear growth rate and the rms linear mass fluctuation on scales of $8 \, h^{-1}\, {\rm Mpc}$ , fσ₈(z_eff) = 0.439 ± 0.048. The accuracy of these measurements is confirmed using an extensive set of mock simulations developed for the quasar sample. The uncertainties on the distance and growth rate measurements have been reduced substantially (∼45 and ∼30 per cent) with respect to the DR14 results. We also perform a BAO-only analysis to cross check the robustness of the methodology of the full-shape analysis. Combining our analysis with the Fourier-space analysis, we arrive at $D^{{\bf c}}_{\rm M}(z_{\rm eff})/r_{\rm drag} = 30.21 \pm 0.79$ , $D^{{\bf c}}_{\rm H}(z_{\rm eff})/r_{\rm drag} = 13.23 \pm 0.47$ , and $f\sigma _8^{{\bf c}}(z_{\rm eff}) = 0.462 \pm 0.045$ .

RU-C

Monthly Notices of the Royal Astronomical Society(01/2021)doi:10.1093/mnras/staa3523

abstract +abstract -

We employ a set of Magneticum cosmological hydrodynamic simulations that span over 15 different cosmologies, and extract masses and concentrations of all well-resolved haloes between z = 0 and 1 for critical overdensities $\Delta _\textrm {vir}, \Delta _{200c}, \Delta _{500c}, \Delta _{2500c}$ and mean overdensity Δ_200m. We provide the first mass-concentration (Mc) relation and sparsity relation (i.e. M_Δ1 - M_Δ2 mass conversion) of hydrodynamic simulations that is modelled by mass, redshift, and cosmological parameters Ω_m, Ω_b, σ₈, h₀ as a tool for observational studies. We also quantify the impact that the Mc relation scatter and the assumption of Navarro-Frank-White (NFW) density profiles have on the uncertainty of the sparsity relation. We find that converting masses with the aid of an Mc relation carries an additional fractional scatter ( $\approx 4{{\ \rm per\ cent}}$ ) originated from deviations from the assumed NFW density profile. For this reason, we provide a direct mass-mass conversion relation fit that depends on redshift and cosmological parameters. We release the package HYDRO_MC, a PYTHON tool that perform all kind of conversions presented in this paper.

MIAPbP

Monthly Notices of the Royal Astronomical Society(01/2021)doi:10.1093/mnras/staa3269

abstract +abstract -

We explore how to mitigate the clustering distortions in Lyman α emitter (LAE) samples caused by the misidentification of the Lyman α ( $\rm {Ly}\,\alpha$ ) wavelength in their $\rm {Ly}\,\alpha$ line profiles. We use the $\rm {Ly}\,\alpha$ line profiles from our previous LAE theoretical model that includes radiative transfer in the interstellar and intergalactic mediums. We introduce a novel approach to measure the systemic redshift of LAEs from their $\rm {Ly}\,\alpha$ line using neural networks. In detail, we assume that for a fraction of the whole LAE population their systemic redshift is determined precisely through other spectral features. We then use this subset to train a neural network that predicts the $\rm {Ly}\,\alpha$ wavelength given an $\rm {Ly}\,\alpha$ line profile. We test two different training sets: (i) the LAEs are selected hom*ogeneously and (ii) only the brightest LAE is selected. In comparison with previous approaches in the literature, our methodology improves significantly the accuracy in determining the $\rm {Ly}\,\alpha$ wavelength. In fact, after applying our algorithm in ideal $\rm {Ly}\,\alpha$ line profiles, we recover the clustering unperturbed down to $1\, {\rm cMpc}\, h^{-1}$ . Then, we test the performance of our methodology in realistic $\rm {Ly}\,\alpha$ line profiles by downgrading their quality. The machine learning technique using the uniform sampling works well even if the $\rm {Ly}\,\alpha$ line profile quality is decreased considerably. We conclude that LAE surveys such as HETDEX would benefit from determining with high accuracy the systemic redshift of a subpopulation and applying our methodology to estimate the systemic redshift of the rest of the galaxy sample.

MIAPbP

Monthly Notices of the Royal Astronomical Society(01/2021)doi:10.1093/mnras/staa3461

abstract +abstract -

The relationship between a galaxy's properties and its circumgalactic medium (CGM) provides a unique view of how galaxies evolve. We present an interesting edge-on (i = 86°) disc galaxy (G1547) where the CGM is probed by a background quasar at a distance of 84 kpc and within 10° of the galaxy major axis. G1547 does not have any detectable CGM absorption down to stringent limits, covering H I (EW_r <0.02 Å, log(N(H I)/cm^-2) < 12.6) and a range of low and high ionization absorption lines (O I, C II, N II, Si II, C III, N III, Si III, C IV, Si IV, N V, and O VI). This system is rare, given the covering fraction of $1.00_{-0.04}^{+0.00}$ for sub-L* galaxies within 50-100 kpc of quasar sightlines. G1547 has a low star formation rate (SFR, 1.1 M_⊙ yr^-1), specific SFR (sSFR, 1.5 × 10^-10 yr^-1), and Σ_SFR (0.06 M_⊙ yr^-1 kpc^-2) and does not exhibit active galactic nucleus or star-formation-driven outflows. Compared to the general population of galaxies, G1547 is in the green valley and has an above average metallicity with a negative gradient. When compared to other H I absorption-selected galaxies, we find that quiescent galaxies with log(sSFR/yr^-1) < -11 have a low probability (4/12) of possessing detectable H I in their CGM, while all galaxies (40/40) with log(sSFR/yr^-1) > -11 have H I absorption. We conclude that sSFR is a good indicator of the presence of H I CGM. Interestingly however, G1547 is the only galaxy with log(sSFR/yr^-1) > -11 that has no detectable CGM. Given the properties of G1547, and its absent CGM, it is plausible that G1547 is undergoing quenching due to a lack of accreting fuel for star formation, with an estimated quenching time-scale of 4 ± 1 Gyr. G1547 provides a unique perspective into the external mechanisms that could explain the migration of galaxies into the green valley.

The Astrophysical Journal(01/2021)doi:10.3847/1538-4357/abcb85

abstract +abstract -

We present details of the Automated Radio Telescope Imaging Pipeline (ARTIP) and the results of a sensitive blind search for H I and OH absorbers at z < 0.4 and z < 0.7, respectively. ARTIP is written in Python 3.6, extensively uses the Common Astronomy Software Application tools and tasks, and is designed to enable the geographically distributed MeerKAT Absorption Line Survey (MALS) team to collaboratively process large volumes of radio interferometric data. We apply it to the first MALS data set obtained using the 64-dish MeerKAT radio telescope and 32 K channel mode of the correlator. With merely 40 minutes on target, we present the most sensitive spectrum of PKS 1830-211 ever obtained and characterize the known H I (z = 0.19) and OH (z = 0.89) absorbers. We further demonstrate ARTIP's capabilities to handle realistic observing scenarios by applying it to a sample of 72 bright radio sources observed with the upgraded Giant Metrewave Radio Telescope (uGMRT) to blindly search for H I and OH absorbers. We estimate the numbers of H I and OH absorbers per unit redshift to be n₂₁(z ∼ 0.18) < 0.14 and n_OH(z ∼ 0.40) < 0.12, respectively, and constrain the cold gas covering factor of galaxies at large impact parameters (50 kpc < ρ < 150 kpc) to be less than 0.022. Due to the small redshift path, Δz ∼ 13 for H I with column density >5.4 × 10¹⁹ cm^-2, the survey has probed only the outskirts of star-forming galaxies at ρ > 30 kpc. MALS with the expected Δz ∼ 10^3-4 will overcome this limitation and provide stringent constraints on the cold gas fraction of galaxies in diverse environments over 0 < z < 1.5.

Astronomy and Astrophysics(01/2021)doi:10.1051/0004-6361/202039736

abstract +abstract -

MIAPbP

Physical Review D(01/2021)doi:10.1103/PhysRevD.103.023501

abstract +abstract -

We present a next-to-next-to-leading (fifth or NNLO) order calculation for the covariance matrix of the matter power spectrum, taking into account the effect of survey window functions. Using the grid-based calculation scheme for the standard perturbation theory, GridSPT, we quickly generate multiple realizations of the nonlinear density fields to fifth order in perturbation theory, then estimate the power spectrum and the covariance matrix from the sample. To the end, we have obtained the non-Gaussian covariance originated from the one-loop trispectrum without explicitly computing the trispectrum. By comparing the GridSPT calculations with the N -body results, we show that NNLO GridSPT result reproduces the N -body results on quasilinear scales, where SPT accurately models nonlinear matter power spectrum. Incorporating the survey window function effect to GridSPT is rather straightforward, and the resulting NNLO covariance matrix also matches well with the N -body results.

RU-D

Astronomy and Computing(01/2021)doi:10.1016/j.ascom.2021.100448

abstract +abstract -

Observational astronomers survey the sky in great detail to gain a better understanding of many types of astronomical phenomena. In particular, the formation and evolution of galaxies, including our own, are a wide field of research. Three dimensional (spatial 3D) scientific visualisation is typically limited to simulated galaxies, due to the inherently two dimensional spatial resolution of Earth-based observations. However, with appropriate means of reconstruction, such visualisation can also be used to bring out the inherent 3D structure that exists in 2D observations of known galaxies, providing new views of these galaxies and visually illustrating the spatial relationships within galaxy groups that are not obvious in 2D. We present a novel approach to reconstruct and visualise 3D representations of nearby galaxies based on observational data using the scientific visualisation software Splotch. We apply our approach to a case study of the nearby barred spiral galaxy known as M83, presenting a new perspective of the M83 local group and highlighting the similarities between our reconstructed views of M83 and other known galaxies of similar inclinations.

Nature Astronomy(01/2021)doi:10.1038/s41550-020-01267-y

abstract +abstract -

The formation and evolutionary processes of galaxy bulges are still unclear, and the presence of young stars in the bulge of the Milky Way is largely debated. We recently demonstrated that Terzan 5, in the Galactic bulge, is a complex stellar system hosting stars with very different ages and a striking chemical similarity to the field population. This indicates that its progenitor was probably one of the giant structures that are thought to generate bulges through coalescence. Here we show that another globular cluster-like system in the bulge (Liller 1) hosts two distinct stellar populations with remarkably different ages: only 1-3 Gyr for the youngest, and 12 Gyr for the oldest, which is impressively similar to the old component of Terzan 5. This discovery classifies Liller 1 and Terzan 5 as sites of recent star formation in the Galactic bulge and provides clear observational proof that the hierarchical assembly of primordial massive structures contributed to the formation of the Milky Way spheroid.

arXiv e-prints(01/2021)e-Print:2101.01729

abstract +abstract -

We analyze a suite of $30$ high resolution zoom-in cosmological hydrodynamic simulations of massive galaxies with stellar masses $M_{\ast} > 10^{10.9} M_\odot$, with the goal of better understanding merger activity in AGN, AGN activity in merging systems, SMBH growth during mergers, and the role of gas content. Using the radiative transfer code \textsc{Powderday}, we generate HST-WFC3 F160W synthetic observations of redshift $0.5 < z < 3$ central galaxies, add noise properties similar to the CANDELS survey, and measure morphological properties from the synthetic images using commonly adopted non-parametric statistics. We compare the distributions of morphological properties measured from the synthetic images with a sample of inactive galaxies and X-ray selected AGN hosts from CANDELS. We study the connection between mergers and AGN activity in the simulations, the synthetic images, and the observed CANDELS sample. We find that, in both the simulations and CANDELS, even the most luminous $(L_{\rm bol} > 10^{45}$ erg s$^{-1})$ AGN in our sample are no more likely than inactive galaxies $(L_{\rm bol} < 10^{43}$ erg s$^{-1})$ to be found in merging systems. We also find that AGN activity is not overall enhanced by mergers, nor enhanced at any specific time in the $1$ Gyr preceding and following a merger. Even gas rich major mergers (stellar mass ratio $>$1:4) do not necessarily enhance AGN activity or significantly grow the central SMBH. We conclude that in the simulated massive galaxies studied here, mergers are not the primary drivers of AGN.

CN-5

RU-D

Astronomy and Astrophysics(01/2021)doi:10.1051/0004-6361/202039335

abstract +abstract -

RU-D

Monthly Notices of the Royal Astronomical Society(01/2021)doi:10.1093/mnras/staa3464

abstract +abstract -

We contrast the gas kinematics and dark matter contents of z = 2 star-forming galaxies (SFGs) from state-of-the-art cosmological simulations within the ΛCDM framework to observations. To this end, we create realistic mock observations of massive SFGs ( $M_*\gt 4\times 10^{10} \, \mathrm{M}_{\odot}$ , SFR >50 M_⊙ yr^-1) from the TNG50 simulation of the IllustrisTNG suite, resembling near-infrared, adaptive-optics assisted integral-field observations from the ground. Using observational line fitting and modelling techniques, we analyse in detail the kinematics of seven TNG50 galaxies from five different projections per galaxy, and compare them to observations of twelve massive SFGs by Genzel et al. (2020). The simulated galaxies show clear signs of disc rotation but mostly exhibit more asymmetric rotation curves, partly due to large intrinsic radial and vertical velocity components. At identical inclination angle, their 1D velocity profiles can vary along different lines of sight by up to Δv = 200 km s^-1. From dynamical modelling we infer rotation speeds and velocity dispersions that are broadly consistent with observational results. We find low central dark matter fractions compatible with observations ( $f_{\rm DM}^v(\lt R_e)=v_{\rm DM}^2(R_e)/v_{\rm circ}^2(R_e)\sim 0.32\pm 0.10$ ), however for disc effective radii R_e that are mostly too small: at fixed R_e the TNG50 dark matter fractions are too high by a factor of ∼2. We speculate that the differences in gas kinematics and dark matter content compared to the observations may be due to physical processes that are not resolved in sufficient detail with the numerical resolution available in current cosmological simulations.

IDSL

RU-E

PNAS(01/2021)doi:10.1073/pnas.2018830118

abstract +abstract -

The central question in the origin of life is to understand how structure can emerge from randomness. The Eigen theory of replication states, for sequences that are copied one base at a time, that the replication fidelity has to surpass an error threshold to avoid that replicated specific sequences become random because of the incorporated replication errors [M. Eigen, Naturwissenschaften 58 (10), 465–523 (1971)]. Here, we showed that linking short oligomers from a random sequence pool in a templated ligation reaction reduced the sequence space of product strands. We started from 12-mer oligonucleotides with two bases in all possible combinations and triggered enzymatic ligation under temperature cycles. Surprisingly, we found the robust creation of long, highly structured sequences with low entropy. At the ligation site, complementary and alternating sequence patterns developed. However, between the ligation sites, we found either an A-rich or a T-rich sequence within a single oligonucleotide. Our modeling suggests that avoidance of hairpins was the likely cause for these two complementary sequence pools. What emerged was a network of complementary sequences that acted both as templates and substrates of the reaction. This self-selecting ligation reaction could be restarted by only a few majority sequences. The findings showed that replication by random templated ligation from a random sequence input will lead to a highly structured, long, and nonrandom sequence pool. This is a favorable starting point for a subsequent Darwinian evolution searching for higher catalytic functions in an RNA world scenario.

Nature Physics(2021)doi:10.1038/s41567-021-01213-3

abstract +abstract -

The healthy growth and maintenance of a biological system depends on the precise spatial organization of molecules within the cell through the dissipation of energy. Reaction-diffusion mechanisms can facilitate this organization, as can directional cargo transport orchestrated by motor proteins, by relying on specific protein interactions. However, transport of material through the cell can also be achieved by active processes based on non-specific, purely physical mechanisms, a phenomenon that remains poorly explored. Here, using a combined experimental and theoretical approach, we discover and describe a hidden function of the Escherichia coli MinDE protein system: in addition to forming dynamic patterns, this system accomplishes the directional active transport of functionally unrelated cargo on membranes. Remarkably, this mechanism enables the sorting of diffusive objects according to their effective size, as evidenced using modular DNA origami-streptavidin nanostructures. We show that the diffusive fluxes of MinDE and non-specific cargo couple via density-dependent friction. This non-specific process constitutes a diffusiophoretic mechanism, as yet unknown in a cell biology setting. This nonlinear coupling between diffusive fluxes could represent a generic physical mechanism for establishing intracellular organization.

RU-A

Acta Physica Polonica B(2021)doi:10.5506/APhysPolB.52.1189

abstract +abstract -

We reemphasize that the ratio $R_{s\mu} \equiv \overline{\mathcal{B}}(B_s\to\mu\bar\mu)/\Delta M_s$ is a measure of the tension of the Standard Model (SM) with latest measurements of $\overline{\mathcal{B}}(B_s\to\mu\bar\mu)$ that does not suffer from the persistent puzzle on the $|V_{cb}|$ determinations from inclusive versus exclusive $b\to c\ell\bar\nu$ decays and which affects the value of the CKM element $|V_{ts}|$ that is crucial for the SM predictions of both $\overline{\mathcal{B}}(B_s\to\mu\bar\mu)$ and $\Delta M_s$, but cancels out in the ratio $R_{s\mu}$. In our analysis we include higher order electroweak and QED corrections und adapt the latest hadronic input to find a tension of about $2\sigma$ for $R_{s\mu}$ measurements with the SM independently of $|V_{ts}|$. We also discuss the ratio $R_{d\mu}$ which could turn out, in particular in correlation with $R_{s\mu}$, to be useful for the search for New Physics, when the data on both ratios improves. Also $R_{d\mu}$ is independent of $|V_{cb}|$ or more precisely $|V_{td}|$.

RU-A

Acta Physica Polonica B(2021)doi:10.5506/APhysPolB.52.7

abstract +abstract -

The ratio $\epsilon'/\epsilon$ measures the size of the direct CP violation in $K_L\to\pi\pi$ decays $(\epsilon^\prime)$ relative to the indirect one described by $\epsilon$ and is very sensitive to new sources of CP violation. As such it played a prominent role in particle physics already for 45 years. Due to the smallness of $\epsilon'/\epsilon$ its measurement required heroic efforts in the 1980s and the 1990s on both sides of the Atlantic with final results presented by NA48 and KTeV collaborations 20 years ago. Unfortunately, even 45 years after the first calculation of $\epsilon'/\epsilon$ we do not know to which degree the Standard Model agrees with this data and how large is the room left for new physics contributions to this ratio. This is due to significant non-perturbative (hadronic) uncertainties accompanied by partial cancellation between the QCD penguin contributions and electroweak penguin contributions. While the significant control over the short distance perturbative effects has been achieved already in the early 1990s, with several improvements since then, different views on the non-perturbative contributions to $\epsilon'/\epsilon$ have been expressed by different authors over last thirty years. In fact even today the uncertainty in the room left for NP contributions to $\epsilon'/\epsilon$ is very significant. My own work on $\epsilon'/\epsilon$ started in 1983 and involved both perturbative and non-perturbative calculations. This writing is a non-technical recollection of the steps which led to the present status of $\epsilon'/\epsilon$ including several historical remarks not known to everybody. The present status of the $\Delta I=1/2$ rule is also summarized. This story is dedicated to Jean-Marc Gerard on the occasion of the 35th anniversary of our collaboration and his 64th birthday.

Mon.Not.Roy.Astron.Soc.(2021)e-Print:2109.09996doi:10.1093/mnras/stab2754

abstract +abstract -

The flat stellar density cores of massive elliptical galaxies form rapidly due to sinking supermassive black holes (SMBHs) in gas-poor galaxy mergers. After the SMBHs form a bound binary, gravitational slingshot interactions with nearby stars drive the core regions towards a tangentially biased stellar velocity distribution. We use collisionless galaxy merger simulations with accurate collisional orbit integration around the central SMBHs to demonstrate that the removal of stars from the centre by slingshot kicks accounts for the entire change in velocity anisotropy. The rate of strong (unbinding) kicks is constant over several hundred Myr at |$\sim 3 \ \mathrm{ M}_\odot\, \rm yr^{-1}$| for our most massive SMBH binary (M_BH = 1.7×10^10 M_⊙). Using a frequency-based orbit classification scheme (box, x-tube, z-tube, rosette), we demonstrate that slingshot kicks mostly affect box orbits with small pericentre distances, leading to a velocity anisotropy of β ≲ −0.6 within several hundred Myr as observed in massive ellipticals with large cores. We show how different SMBH masses affect the orbital structure of the merger remnants and present a kinematic tomography connecting orbit families to integral field kinematic features. Our direct orbit classification agrees remarkably well with a modern triaxial Schwarzschild analysis applied to simulated mock kinematic maps.

CN-4

PhD Thesis

RU-C

(7/2020)link

abstract +abstract -

There is a great need for independent accurate measurements of the Hubble constant (H0). We establish a new one-step method to determine H0 based on radiative transfer modeling of type II supernovae and demonstrate its utility in a proof-of-principle measurement. In this first-ever application of the tailored-expanding-photosphere method in the Hubble flow, we find H0=72.3 ± 2.9 km s-1 Mpc-1 in good agreement with state-of-the-art results.

CN-7

RU-A

Progress in Particle and Nuclear Physics(5/2020)doi:10.1016/j.ppnp.2020.103770

abstract +abstract -

We review the present status of the experimental and theoretical developments in the field of strangeness in nuclei and neutron stars. We start by discussing the K ¯ N interaction, that is governed by the presence of the Λ(1405) . We continue by showing the two-pole nature of the Λ(1405) , and the production mechanisms in photon-, pion-, kaon-induced reactions as well as proton-proton collisions, while discussing the formation of K ¯ NN bound states. We then move to the theoretical and experimental analysis of the properties of kaons and antikaons in dense nuclear matter, paying a special attention to kaonic atoms and the analysis of strangeness creation and propagation in nuclear collisions. Next, we examine the ϕ meson and the advances in photoproduction, proton-induced and pion-induced reactions, so as to understand its properties in dense matter. Finally, we address the dynamics of hyperons with nucleons and nuclear matter, and the connection to the phases of dense matter with strangeness in the interior of neutron stars.

CN-8

PhD Thesis

RU-E

(2/2020)doi:10.5282/edoc.25726

abstract +abstract -

Spatiotemporal organization is key to transforming a “bag of molecules” into a functional cell capable of exerting complex tasks, such as chromosome segregation and cell division. In bacteria, molecular transport and positioning relies on protein systems centered around ParA-type ATPases, which serve as nucleotide-dependent molecular switches. Of these systems, the Escherichia coli MinCDE system, which self-organizes by a reaction-diffusion mechanism, has been studied the most extensively. Based on the ATPase MinD, its ATPase-activating protein MinE, the passenger protein MinC and the membrane as a reaction matrix, this minimal oscillator defines the midcell position in E. coli. In this thesis, I set out to further refine the understanding of the MinDE self-organization mechanism and to decipher additional roles of the MinDE system, by taking advantage of the established in vitro reconstitution assay of Min(C)DE self-organization. [...]

RU-D

Monthly Notices of the Royal Astronomical Society(12/2020)doi:10.1093/mnras/staa2933

abstract +abstract -

The disc surrounding PDS 70, with two directly imaged embedded giant planets, is an ideal laboratory to study planet-disc interaction. We present 3D smoothed particle hydrodynamics simulations of the system. In our simulations, planets, which are free to migrate and accrete mass, end up in a locked resonant configuration that is dynamically stable. We show that features observed at infrared (scattered light) and millimetre (thermal continuum) wavelengths are naturally explained by the accretion stream on to the outer planet, without requiring a circumplanetary disc around Planet c. We post-processed our near-infrared synthetic images in order to account for observational biases known to affect high-contrast images. Our successful reproduction of the observations indicates that planet-disc dynamical interactions alone are sufficient to explain the observations of PDS 70.

Mon.Not.Roy.Astron.Soc.(12/2020)e-Print:2012.15340doi:10.1093/mnras/stab1349

abstract +abstract -

Blazars are among the most studied sources in high-energy astrophysics as they form the largest fraction of extragalactic gamma-ray sources and are considered prime candidates for being the counterparts of high-energy astrophysical neutrinos. Their reliable identification amid the many faint radio sources is a crucial step for multimessenger counterpart associations. As the astronomical community prepares for the coming of a number of new facilities able to survey the non-thermal sky at unprecedented depths, from radio to gamma-rays, machine-learning techniques for fast and reliable source identification are ever more relevant. The purpose of this work was to develop a deep learning architecture to identify Blazar within a population of active galactic nucleus (AGN) based solely on non-contemporaneous spectral energy distribution information, collected from publicly available multifrequency catalogues. This study uses an unprecedented amount of data, with spectral energy distributions (SEDs) for ≈14 000 sources collected with the Open Universe VOU-Blazars tool. It uses a convolutional long short-term memory neural network purposefully built for the problem of SED classification, which we describe in detail and validate. The network was able to distinguish Blazars from other types of active galactic nuclei (AGNs) to a satisfying degree (achieving a receiver operating characteristic area under curve of 0.98), even when trained on a reduced subset of the whole sample. This initial study does not attempt to classify Blazars among their different sub-classes, or quantify the likelihood of any multifrequency or multimessenger association, but is presented as a step towards these more practically oriented applications.

RU-C

JCAP(12/2020)e-Print:2012.04637doi:10.1088/1475-7516/2021/05/069

abstract +abstract -

Halo occupation distribution (HOD) models describe the number of galaxies that reside in different haloes, and are widely used in galaxy-halo connection studies using the halo model (HM). Here, we introduce and study HOD response functions R

Eur.Phys.J.C(12/2020)e-Print:2012.15629doi:10.1140/epjc/s10052-021-09198-2

abstract +abstract -

Predictions for the Higgs masses are a distinctive feature of supersymmetric extensions of the Standard Model, where they play a crucial role in constraining the parameter space. The discovery of a Higgs boson and the remarkably precise measurement of its mass at the LHC have spurred new efforts aimed at improving the accuracy of the theoretical predictions for the Higgs masses in supersymmetric models. The “Precision SUSY Higgs Mass Calculation Initiative” (KUTS) was launched in 2014 to provide a forum for discussions between the different groups involved in these efforts. This report aims to present a comprehensive overview of the current status of Higgs-mass calculations in supersymmetric models, to document the many advances that were achieved in recent years and were discussed during the KUTS meetings, and to outline the prospects for future improvements in these calculations.

Phys.Rev.D(12/2020)e-Print:2012.06594doi:10.1103/PhysRevD.103.063033

abstract +abstract -

We assess the occurrence of fast neutrino flavor instabilities in two three-dimensional state-of-the-art core-collapse supernova simulations performed using a two-moment three-species neutrino transport scheme: one with an exploding 9M⊙ and one with a nonexploding 20M⊙ model. Apart from confirming the presence of fast instabilities occurring within the neutrino decoupling and the supernova pre-shock regions, we detect flavor instabilities in the post-shock region for the exploding model. These instabilities are likely to be scattering-induced. In addition, the failure in achieving a successful explosion in the heavier supernova model seems to seriously hinder the occurrence of fast instabilities in the post-shock region. This is a consequence of the large matter densities behind the stalled or retreating shock, which implies high neutrino scattering rates and thus more isotropic distributions of neutrinos and antineutrinos. Our findings suggest that the supernova model properties and the fate of the explosion can remarkably affect the occurrence of fast instabilities. Hence, a larger set of realistic hydrodynamical simulations of the stellar collapse is needed in order to make reliable predictions on the flavor conversion physics.

Physical Review Letters(12/2020)doi:10.1103/PhysRevLett.125.251801

abstract +abstract -

Neutrinos in a core-collapse supernova can undergo fast flavor conversions with a possible impact on the explosion mechanism and nucleosynthesis. We perform the first nonlinear simulations of fast conversions in the presence of three neutrino flavors. The recent supernova simulations with muon production call for such an analysis, as they relax the standard ν_{μ ,τ}=ν_{¯ μ ,τ} (two-flavor) assumption. Our results show the significance of muon and tau lepton number angular distributions, together with the traditional electron lepton number ones. Indeed, our three-flavor results are potentially very different from two-flavor ones. These results strengthen the need to further investigate the occurrence of fast conversions in supernova simulation data, including the degeneracy breaking of mu and tau neutrinos.

abstract +abstract -

LiteBIRD is JAXA Strategic Large Mission for the late 2020s that aims to observe the large-scale B-mode polarization pattern of the cosmic microwave background. One of its telescopes, the Low Frequency Telescope (LFT), has a crossed-Dragone design and observes at 34-161 GHz with a field of view of 18° x 9°. Because a miscalibration of the polarization angles mixes E- and B-mode polarization, we have measured the variation of the polarization angles in the field of view of a 1/4-scaled LFT antenna at 140-220 GHz, which corresponds to 35-55 GHz for the full-scale LFT, considering a scaling of the wavelength. We placed a collimated-wave source near the scaled-LFT aperture and rotated the polarization angle of the LFT feed. The measurements were explained well with a simple Jones matrix calculation, and the fitting errors of the polarization angles were less than 0.1'. We also measured the polarization angles by rotating the polarization direction in the scaled-LFT aperture, and the results were consistent with the angles measured by rotating the feed polarization at the +/-10" level, except at the lowest frequencies. The polarization angle at the edges of the focal plane varied from that at the center by up to around a degree, with larger variation at lower frequencies. We evaluated the polarization angles for both Pol-X and Pol-Y feeds, and the results with Pol-Y showed a trend consistent with ray-tracing simulations. The results for Pol-X showed the opposite trend of the polarization rotation direction and larger angle variations.

ApJ(12/2020)e-Print:2010.03693doi:10.3847/1538-4357/abc339

abstract +abstract -

Observations of debris disks, the products of the collisional evolution of rocky planetesimals, can be used to trace planetary activity across a wide range of stellar types. The most common end points of stellar evolution are no exception as debris disks have been observed around several dozen white dwarf stars. But instead of planetary formation, post-main-sequence debris disks are a signpost of planetary destruction, resulting in compact debris disks from the tidal disruption of remnant planetesimals. In this work, we present the discovery of five new debris disks around white dwarf stars with gaseous debris in emission. All five systems exhibit excess infrared radiation from dusty debris, emission lines from gaseous debris, and atmospheric absorption features indicating on-going accretion of metal-rich debris. In four of the systems, we detect multiple metal species in emission, some of which occur at strengths and transitions previously unseen in debris disks around white dwarf stars. Our first year of spectroscopic follow-up hints at strong variability in the emission lines that can be studied in the future, expanding the range of phenomena these post-main-sequence debris disks exhibit.

abstract +abstract -

The LiteBIRD satellite is planned to be launched by JAXA in the late 2020s. Its main purpose is to observe the large-scale B-mode polarization in the Cosmic Microwave Background (CMB) anticipated from the Inflation theory. LiteBIRD will observe the sky for three years at the second Lagrangian point (L2) of the Sun-Earth system. Planck was the predecessor for observing the CMB at L2, and the onboard High Frequency Instrument (HFI) suffered contamination by glitches caused by the cosmic-ray (CR) hits. We consider the CR hits can also be a serious source of the systematic uncertainty for LiteBIRD. Thus, we have started a comprehensive end-to-end simulation study to assess impact of the CR hits for the LiteBIRD detectors. Here, we describe procedures to make maps and power spectra from the simulated time-ordered data, and present initial results. Our initial estimate is that ClBB by CR is ~ 2 ×10-6 μK2CMB in a one-year observation with 12 detectors assuming that the noise is 1 aW/ √ Hz for the differential mode of two detectors constituting a polarization pair.

MIAPbP

The Astrophysical Journal(12/2020)doi:10.3847/1538-4357/abc42f

abstract +abstract -

The connection between galaxy star formation rate (SFR) and dark matter (DM) is of paramount importance for the extraction of cosmological information from next-generation spectroscopic surveys that will target emission line star-forming galaxies. Using publicly available mock galaxy catalogs obtained from various semianalytic models (SAMs), we explore the SFR-DM connection in relation to the speed-from-light method for inferring the growth rate, f, from luminosity/SFR shifts. Emphasis is given to the dependence of the SFR distribution on the environmental density on scales of 10-100 s Mpc. We show that the application of the speed-from-light method to a Euclid-like survey is not biased by environmental effects. In all models, the precision on the measured β = f/b parameter is σ_β ≲ 0.17 at z = 1. This translates into errors of σ_f ∼ 0.22 and ${\sigma }_{(f{\sigma }_{8})}\sim 0.1$ without invoking assumptions on the mass power spectrum. These errors are in the same ballpark as recent analyses of the redshift space distortions in galaxy clustering. In agreement with previous studies, the bias factor, b, is roughly a scale-independent, constant function of the SFR for star-forming galaxies. Its value at z = 1 ranges from 1.2 to 1.5 depending on the SAM recipe. Although in all SAMs, denser environments host galaxies with higher stellar masses, the dependence of the SFR on the environment is more involved. In most models, the SFR probability distribution is skewed to larger values in denser regions. One model exhibits an inverted trend, where high SFR is suppressed in dense environments.

abstract +abstract -

LiteBIRD is a JAXA-led strategic Large-Class satellite mission designed to measure the polarization of the cosmic microwave background and cosmic foregrounds from 34 to 448 GHz across the entire sky from L2 in the late 2020's. The primary focus of the mission is to measure primordially generated B-mode polarization at large angular scales. Beyond its primary scientific objective LiteBIRD will generate a data-set capable of probing a number of scientific inquiries including the sum of neutrino masses. The primary responsibility of United States will be to fabricate the three flight model focal plane units for the mission. The design and fabrication of these focal plane units is driven by heritage from ground based experiments and will include both lenslet-coupled sinuous antenna pixels and horn-coupled orthom*ode transducer pixels. The experiment will have three optical telescopes called the low frequency telescope, mid frequency telescope, and high frequency telescope each of which covers a portion of the mission's frequency range. JAXA is responsible for the construction of the low frequency telescope and the European Consortium is responsible for the mid- and high- frequency telescopes. The broad frequency coverage and low optical loading conditions, made possible by the space environment, require development and adaptation of detector technology recently deployed by other cosmic microwave background experiments. This design, fabrication, and characterization will take place at UC Berkeley, NIST, Stanford, and Colorado University, Boulder. We present the current status of the US deliverables to the LiteBIRD mission.

RU-B

Physics Letters B(12/2020)doi:10.1016/j.physletb.2020.135929

abstract +abstract -

We demonstrate that megaton-mass neutrino telescopes are able to observe the signal from long-lived particles beyond the Standard Model, in particular the stau, the supersymmetric partner of the tau lepton. Its signature is an excess of charged particle tracks with horizontal arrival directions and energy deposits between 0.1 and 1 TeV inside the detector. We exploit this previously-overlooked signature to search for stau particles in the publicly available IceCube data. The data shows no evidence of physics beyond the Standard Model. We derive a new lower limit on the stau mass of 320 GeV (95% C.L.) and estimate that this new approach, when applied to the full data set available to the IceCube collaboration, will reach word-leading sensitivity to the stau mass (m_τ∼ = 450 GeV).

RU-C

abstract +abstract -

LiteBIRD has been selected as JAXA's strategic large mission in the 2020s, to observe the cosmic microwave background (CMB) B-mode polarization over the full sky at large angular scales. The challenges of LiteBIRD are the wide field-of-view (FoV) and broadband capabilities of millimeter-wave polarization measurements, which are derived from the system requirements. The possible paths of stray light increase with a wider FoV and the far sidelobe knowledge of -56 dB is a challenging optical requirement. A crossed-Dragone configuration was chosen for the low frequency telescope (LFT : 34-161 GHz), one of LiteBIRD's onboard telescopes. It has a wide field-of-view (18° x 9°) with an aperture of 400 mm in diameter, corresponding to an angular resolution of about 30 arcminutes around 100 GHz. The focal ratio f/3.0 and the crossing angle of the optical axes of 90° are chosen after an extensive study of the stray light. The primary and secondary reflectors have rectangular shapes with serrations to reduce the diffraction pattern from the edges of the mirrors. The reflectors and structure are made of aluminum to proportionally contract from warm down to the operating temperature at 5 K. A 1/4 scaled model of the LFT has been developed to validate the wide field-of-view design and to demonstrate the reduced far sidelobes. A polarization modulation unit (PMU), realized with a half-wave plate (HWP) is placed in front of the aperture stop, the entrance pupil of this system. A large focal plane with approximately 1000 AlMn TES detectors and frequency multiplexing SQUID amplifiers is cooled to 100 mK. The lens and sinuous antennas have broadband capability. Performance specifications of the LFT and an outline of the proposed verification plan are presented.

The Astrophysical Journal(12/2020)doi:10.3847/1538-4357/abc5b9

abstract +abstract -

We present new observations with the Atacama Large Millimeter/submillimeter Array of the 122 and 205 μm fine-structure line emission of singly ionized nitrogen in a strongly lensed starburst galaxy at z = 2.6. The 122/205 μm [N II] line ratio is sensitive to electron density, ${n}_{{\rm{e}}}$, in the ionized interstellar medium, and we use this to measure n_e ≍ 300 cm^-3, averaged across the galaxy. This is over an order of magnitude higher than the Milky Way average, comparable to localized Galactic star-forming regions. Combined with observations of the atomic carbon (C I) and carbon monoxide (CO J = 4-3) in the same system, we reveal the conditions in this intensely star-forming system. The majority of the molecular interstellar medium has been driven to high density, and the resultant conflagration of star formation produces a correspondingly dense ionized phase, presumably colocated with myriad H II regions that litter the gas-rich disk.

RU-C

abstract +abstract -

We present a breadboard model development status of the polarization modulator unit (PMU) for a low-frequency telescope (LFT) of the LiteBIRD space mission. LiteBIRD is a next-generation cosmic microwave background polarization satellite to measure the primordial B-mode with the science goal of σr < 0.001. The baseline design of LiteBIRD consists of reflective low-frequency and refractive medium-and-high-frequency telescopes. Each telescope employs the PMU based on a continuous rotating half-wave plate (HWP) at the aperture. The PMU is a critical instrument for the LiteBIRD to achieve the science goal because it significantly suppresses 1/f noise and mitigates systematic uncertainties. The LiteBIRD LFT PMU consists of a broadband achromatic HWP and a cryogenic rotation mechanism. In this presentation, we discuss requirements, design and systematic studies of the PMU, and we report the development status of the broadband HWP and the space-compatible cryogenic rotation mechanism.

abstract +abstract -

The LiteBIRD mission is a JAXA strategic L-class mission for all sky CMB surveys which will be launched in the 2020s. The main target of the mission is the detection of primordial gravitational waves with a sensitivity of the tensor-to-scalar ratio δr<0.001. The polarization modulator unit (PMU) represents a critical and powerful component to suppress 1/f noise contribution and mitigate systematic uncertainties induced by detector gain drift, both for the high-frequency telescope (HFT) and for the mid-frequency telescope (MFT). Each PMU is based on a continuously-rotating transmissive half-wave plate (HWP) held by a superconducting magnetic bearing in a 5K environment. In this contribution we will present the design and expected performance of the LiteBIRD PMUs and testing performed on every PMU subsystem with a room-temperature rotating disk used as a stand-in for the cryogenic HWP rotor.

abstract +abstract -

The electromagnetic interference (EMI) is becoming an increasingly important factor in the spacecraft design equipped with highly sensitive detectors. This is particularly the case for LiteBIRD, in which the TES bolometers are exposed to space through the optical path. A particular concern is radiative interference caused by the X-band transmission during the ground communication. As the end-to-end verification test will be conducted in a later phase of the development, we need to derisk the concern early using simulation. In this report, we present the result of the EMI effects in the 1-GHz frequency range based on the electromagnetic simulation using a finite difference time domain (FDTD) solver. We modeled the dominant large structures of the spacecraft, calculated the spatial transmission of the antenna power, and estimated the electric field strength at the detector focal plane. The simulation results helped constrain aspects of the LiteBIRD satellite, such as the forward/backward ratio of the transmission antenna, to reduce the coupling between the antenna and the detectors.

abstract +abstract -

LiteBIRD is a JAXA strategic L-class mission devoted to the measurement of polarization of the Cosmic Microwave Background, searching for the signature of primordial gravitational waves in the B-modes pattern of the polarization. The onboard instrumentation includes a Middle and High Frequency Telescope (MHFT), based on a pair of cryogenically cooled refractive telescopes covering, respectively, the 89-224 GHz and the 166-448 GHz bands. Given the high target sensitivity and the careful systematics control needed to achieve the scientific goals of the mission, optical modeling and characterization are performed with the aim to capture most of the physical effects potentially affecting the real performance of the two refractors. We describe the main features of the MHFT, its design drivers and the major challenges in system optimization and characterization. We provide the current status of the development of the optical system and we describe the current plan of activities related to optical performance simulation and validation.

Astronomy and Astrophysics(12/2020)doi:10.1051/0004-6361/202037757

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We present the HOLISMOKES programme on strong gravitational lensing of supernovae (SNe) as a probe of SN physics and cosmology. We investigate the effects of microlensing on early-phase SN Ia spectra using four different SN explosion models. We find that distortions of SN Ia spectra due to microlensing are typically negligible within ten rest-frame days after a SN explosion (< 1% distortion within the 1σ spread and ≲10% distortion within the 2σ spread). This shows the great prospects of using lensed SNe Ia to obtain intrinsic early-phase SN spectra for deciphering SN Ia progenitors. As a demonstration of the usefulness of lensed SNe Ia for cosmology, we simulate a sample of mock lensed SN Ia systems that are expected to have accurate and precise time-delay measurements in the era of the Rubin Observatory Legacy Survey of Space and Time (LSST). Adopting realistic yet conservative uncertainties on their time-delay distances and lens angular diameter distances, of 6.6% and 5%, respectively, we find that a sample of 20 lensed SNe Ia would allow us to constrain the Hubble constant (H₀) with 1.3% uncertainty in the flat ΛCDM cosmology. We find a similar constraint on H₀ in an open ΛCDM cosmology, while the constraint degrades to 3% in a flat wCDM cosmology. We anticipate lensed SNe to be an independent and powerful probe of SN physics and cosmology in the upcoming LSST era.

RU-A

Journal of High Energy Physics(12/2020)doi:10.1007/JHEP12(2020)097

abstract +abstract -

Recently the RBC-UKQCD lattice QCD collaboration presented new results for the hadronic matrix elements relevant for the ratio ɛ'/ɛ in the Standard Model (SM) albeit with significant uncertainties. With the present knowledge of the Wilson coefficients and isospin breaking effects there is still a sizable room left for new physics (NP) contributions to ɛ'/ɛ which could both enhance or suppress this ratio to agree with the data. The new SM value for the K⁰ - K^¯0 mass difference ΔM_K from RBC-UKQCD is on the other hand by 2σ above the data hinting for NP required to suppress ΔM_K. Simultaneously the most recent results for K⁺ → π⁺ν ν ¯ from NA62 and for K_L → π⁰ν ν ¯ from KOTO still allow for significant NP contributions. We point out that the suppression of ΔM_K by NP requires the presence of new CP-violating phases with interesting implications for K → πν ν ¯, K_S → μ⁺μ^- and K_L → π⁰ℓ⁺ℓ^- decays. Considering a Z'-scenario within the SMEFT we analyze the dependence of all these observables on the size of NP still allowed by the data on ɛ'/ɛ. The hinted ΔM_K anomaly together with the ɛ_K constraint implies in the presence of only left-handed (LH) or right-handed (RH) flavour-violating Z' couplings strict correlation between K⁺ → π⁺ν ν ¯ and K_L → π⁰ν ν ¯ branching ratios so that they are either simultaneously enhanced or suppressed relative to SM predictions. An anticorrelation can only be obtained in the presence of both LH and RH couplings. Interestingly, the NP QCD penguin scenario for ɛ'/ɛ is excluded by SMEFT renormalization group effects in ɛ_K so that NP effects in ɛ'/ɛ are governed by electroweak penguins. We also investigate for the first time whether the presence of a heavy Z' with flavour violating couplings could generate through top Yukawa renormalization group effects FCNCs mediated by the SM Z-boson. The outcome turns out to be very interesting.

MIAPbP

Journal of High Energy Physics(12/2020)doi:10.1007/JHEP12(2020)076

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The double copy suggests that the basis of the dynamics of general relativity is Yang-Mills theory. Motivated by the importance of the relativistic two-body problem, we study the classical dynamics of colour-charged particle scattering from the perspective of amplitudes, rather than equations of motion. We explain how to compute the change of colour, and the radiation of colour, during a classical collision. We apply our formalism at next-to-leading order for the colour change and at leading order for colour radiation.

Physical Review Letters(12/2020)doi:10.1103/PhysRevLett.125.258301

abstract +abstract -

A hallmark of topological phases is the occurrence of topologically protected modes at the system's boundary. Here, we find topological phases in the antisymmetric Lotka-Volterra equation (ALVE). The ALVE is a nonlinear dynamical system and describes, for example, the evolutionary dynamics of a rock-paper-scissors cycle. On a one-dimensional chain of rock-paper-scissor cycles, topological phases become manifest as robust polarization states. At the transition point between left and right polarization, solitary waves are observed. This topological phase transition lies in symmetry class D within the "tenfold way" classification as also realized by 1D topological superconductors.

MIAPbP

Physics of the Dark Universe(12/2020)doi:10.1016/j.dark.2020.100624

abstract +abstract -

Due to the inverse Primakoff effect, it has been shown that when axions mix with a DC B →-field, the resulting electrical action will produce an AC electromotive force, which oscillates at the Compton frequency of the axion. As in standard electrodynamics, this electromotive force may be modelled as an oscillating effective impressed magnetic current boundary source. We use this result to calculate the sensitivity of new experiments to low-mass axions using the quasi-static technique, defined as when the Compton wavelength of the axion is greater than the dimensions of the experiment. First, we calculate the current induced in a straight conducting wire (electric dipole antenna) in the limit where the DC B →-field can be considered as spatially constant and show that it has a sensitivity proportional to the axion mass. Following this we extend the topology by making use of the full extent of the spatially varying DC B →-field of the electromagnet. This is achieved by transforming the 1D conducting wire to a 2D winding with inductance, to fully link the effective magnetic current boundary source and hence couple to the full axion induced electrical action (or electromotive force). We investigate two different topologies: The first uses a single winding, and couples to the effective short circuit current generated in the winding, which is optimally read out using a sensitive low impedance SQUID amplifier: The second technique uses multiple windings, with every turn effectively increasing the induced voltage, which is proportional to the winding number. The read out of this configuration is optimised by implementing a cryogenic low-noise high input impedance voltage amplifier. The end result is the realisation of new Broadband Electrical Action Sensing Techniques with orders of magnitude improved sensitivity over current low-mass axion experiments, with a sensitivity linearly proportional to the axion-photon coupling and capable of detecting QCD dark matter axions in the mass range of 10^-12 - 10^-8 eV and below.

CN-4

MIAPbP

RU-C

Journal of Cosmology and Astroparticle Physics(12/2020)doi:10.1088/1475-7516/2020/12/023

abstract +abstract -

We report novel cosmological constraints obtained from cosmic voids in the final BOSS DR12 dataset. They arise from the joint analysis of geometric and dynamic distortions of average void shapes (i.e., the stacked void-galaxy cross-correlation function) in redshift space. Our model uses tomographic deprojection to infer real-space void profiles and self-consistently accounts for the Alco*ck-Paczynski (AP) effect and redshift-space distortions (RSD) without any prior assumptions on cosmology or structure formation. It is derived from first physical principles and provides an extremely good description of the data at linear perturbation order. We validate this model with the help of mock catalogs and apply it to the final BOSS data to constrain the RSD and AP parameters f/b and D_A H/c, where f is the linear growth rate, b the linear galaxy bias, D_A the comoving angular diameter distance, H the Hubble rate, and c the speed of light. In addition, we include two nuisance parameters in our analysis to marginalize over potential systematics. We obtain f/b=0.540±0.091 and D_A H/c=0.588±0.004 from the full void sample at a mean redshift of z=0.51. In a flat ΛCDM cosmology, this implies Ω_m=0.312±0.020 for the present-day matter density parameter. When we use additional information from the survey mocks to calibrate our model, these constraints improve to f/b=0.347±0.023, D_A H/c=0.588±0.003, and Ω_m = 0.310 ± 0.017. However, we emphasize that the calibration depends on the specific model of cosmology and structure formation assumed in the mocks, so the calibrated results should be considered less robust. Nevertheless, our calibration-independent constraints are among the tightest of their kind to date, demonstrating the immense potential of using cosmic voids for cosmology in current and future data.

Astronomy and Astrophysics(12/2020)doi:10.1051/0004-6361/202038346

abstract +abstract -

RU-A

Journal of High Energy Physics(12/2020)doi:10.1007/JHEP12(2020)187

abstract +abstract -

We present a model-independent anatomy of the ΔF = 2 transitions K⁰-K^¯0, B_s,d-B_{¯s ,d} and D⁰-D^¯0 in the context of the Standard Model Effective Field Theory (SMEFT). We present two master formulae for the mixing amplitude [M₁₂]_BSM. One in terms of the Wilson coefficients (WCs) of the Low-Energy Effective Theory (LEFT) operators evaluated at the electroweak scale μ_ew and one in terms of the WCs of the SMEFT operators evaluated at the BSM scale Λ. The coefficients P_a^ij entering these formulae contain all the information below the scales μ_ew and Λ, respectively. Renormalization group effects from the top-quark Yukawa coupling play the most important role. The collection of the individual contributions of the SMEFT operators to [M₁₂]_BSM can be considered as the SMEFT atlas of ΔF = 2 transitions and constitutes a travel guide to such transitions far beyond the scales explored by the LHC. We emphasize that this atlas depends on whether the down-basis or the up-basis for SMEFT operators is considered. We illustrate this technology with tree-level exchanges of heavy gauge bosons (Z', G') and corresponding heavy scalars.

RU-C

abstract +abstract -

LiteBIRD, the Lite (Light) satellite for the study of B-mode polarization and Inflation from cosmic background Radiation Detection, is a space mission for primordial cosmology and fundamental physics. JAXA selected LiteBIRD in May 2019 as a strategic large-class (L-class) mission, with its expected launch in the late 2020s using JAXA's H3 rocket. LiteBIRD plans to map the cosmic microwave background (CMB) polarization over the full sky with unprecedented precision. Its main scientific objective is to carry out a definitive search for the signal from cosmic inflation, either making a discovery or ruling out well-motivated inflationary models. The measurements of LiteBIRD will also provide us with an insight into the quantum nature of gravity and other new physics beyond the standard models of particle physics and cosmology. To this end, LiteBIRD will perform full-sky surveys for three years at the Sun-Earth Lagrangian point L2 for 15 frequency bands between 34 and 448 GHz with three telescopes, to achieve a total sensitivity of 2.16 μK-arcmin with a typical angular resolution of 0.5° at 100 GHz. We provide an overview of the LiteBIRD project, including scientific objectives, mission requirements, top-level system requirements, operation concept, and expected scientific outcomes.

Physical Review D(12/2020)doi:10.1103/PhysRevD.102.123511

abstract +abstract -

It is common to express cosmological measurements in units of h^-1 Mpc . Here, we review some of the complications that originate from this practice. A crucial problem caused by these units is related to the normalization of the matter power spectrum, which is commonly characterized in terms of the linear-theory rms mass fluctuation in spheres of radius 8 h^-1 Mpc , σ₈. This parameter does not correctly capture the impact of h on the amplitude of density fluctuations. We show that the use of σ₈ has caused critical misconceptions for both the so-called σ₈ tension regarding the consistency between low-redshift probes and cosmic microwave background data and the way in which growth-rate estimates inferred from redshift-space distortions are commonly expressed. We propose to abandon the use of h^-1 Mpc units in cosmology and to characterize the amplitude of the matter power spectrum in terms of σ₁₂, defined as the mass fluctuation in spheres of radius 12 Mpc, whose value is similar to the standard σ₈ for h ∼0.67 .

RU-C

abstract +abstract -

LiteBIRD is a JAXA-led Strategic Large-Class mission designed to search for the existence of the primordial gravitational waves produced during the inflationary phase of the Universe, through the measurements of their imprint onto the polarization of the cosmic microwave background (CMB). These measurements, requiring unprecedented sensitivity, will be performed over the full sky, at large angular scales, and over 15 frequency bands from 34 GHz to 448 GHz. The LiteBIRD instruments consist of three telescopes, namely the Low-, Medium-and High-Frequency Telescope (respectively LFT, MFT and HFT). We present in this paper an overview of the design of the Medium-Frequency Telescope (89{224 GHz) and the High-Frequency Telescope (166{448 GHz), the so-called MHFT, under European responsibility, which are two cryogenic refractive telescopes cooled down to 5 K. They include a continuous rotating half-wave plate as the first optical element, two high-density polyethylene (HDPE) lenses and more than three thousand transition-edge sensor (TES) detectors cooled to 100 mK. We provide an overview of the concept design and the remaining specific challenges that we have to face in order to achieve the scientific goals of LiteBIRD.

RU-D

The Astrophysical Journal(12/2020)doi:10.3847/1538-4357/abb242

abstract +abstract -

Whereas cold dark matter (CDM) simulations predict central dark matter cusps with densities that diverge as ρ(r) ∼ 1/r, observations often indicate constant-density cores with finite central densities ρ₀ and a flat density distribution within a core radius r₀. This paper investigates whether this core-cusp problem can be solved by fuzzy dark matter (FDM), a hypothetical particle with a mass of the order of m ≍ 10^-22 eV and a corresponding de Broglie wavelength on astrophysical scales. We show that galaxies with CDM halo virial masses M_vir ≤ 10¹¹M_⊙ follow two core-scaling relations. In addition to the well-known universal core column density Σ₀ ≡ ρ₀ × r₀ = 75 ${M}_{\odot }$ pc^-2, core radii increase with virial masses as r₀ ∼ ${M}_{\mathrm{vir}}^{\gamma }$ with γ of order unity. Using the simulations by Schive et al. we demonstrate that FDM can explain the r₀-M_vir scaling relation if the virial masses of the observed galaxy sample scale with the formation redshift z as M_vir ∼ (1 + z)^-0.4. The observed constant Σ₀ is however in complete disagreement with FDM cores which are characterized by a steep dependence Σ₀ ∼ r ${}_{0}^{-3}$ , independent of z. More high-resolution simulations are now required to confirm the simulations of Schive et al. and explore the transition region between the soliton core and the surrounding halo. If these results hold, FDM can be ruled out as the origin of observed dark matter cores and other physical processes are required to account for their formation.

The Astrophysical Journal(12/2020)doi:10.3847/1538-4357/abc429

abstract +abstract -

Large galaxies may contain an "atmosphere" of hot interstellar X-ray gas, and the temperature and radial density profile of this gas can be used to measure the total mass of the galaxy contained within a given radius r. We use this technique for 102 early-type galaxies with stellar masses M_⋆ > 10¹⁰M_⊙, to evaluate the mass fraction of dark matter (DM) within the fiducial radius r = 5r_e, denoted f₅ = f_DM(5r_e). On average, these systems have a median $\overline{{f}_{5}}\simeq 0.8\mbox{--}0.9$ with a typical galaxy-to-galaxy scatter ±0.15. Comparisons with mass estimates made through the alternative techniques of satellite dynamics (e.g., velocity distributions of globular clusters, planetary nebulae, satellite dwarfs) as well as strong lensing show encouraging consistency over the same range of stellar mass. We find that many of the disk galaxies (S0/SA0/SB0) have a significantly higher mean f₅ than do the pure ellipticals, by Δf₅ ≃ 0.1. We suggest that this higher level may be a consequence of sparse stellar haloes and quieter histories with fewer major episodes of feedback or mergers. Comparisons are made with the Magneticum Pathfinder suite of simulations for both normal and centrally dominant "Brightest Cluster" galaxies. Though the observed data exhibit somewhat larger scatter at a given galaxy mass than do the simulations, the mean level of DM mass fraction for all classes of galaxies is in good first-order agreement with the simulations. Finally, we find that the group galaxies with stellar masses near M_⋆ ∼ 10¹¹M_⊙ have relatively more outliers at low f₅ than in other mass ranges, possibly the result of especially effective AGN feedback in that mass range leading to expansion of their DM halos.

Physical Review D(12/2020)doi:10.1103/PhysRevD.102.123517

abstract +abstract -

We compute the covariance of the galaxy power spectrum multipoles in perturbation theory, including the effects of nonlinear evolution, nonlinear and nonlocal bias, radial redshift-space distortions, arbitrary survey window, and shot noise. We rewrite the power spectrum FKP estimator in terms of the usual windowed galaxy fluctuations and the fluctuations in the number of galaxies inside the survey volume. We show that this leads to a stronger supersample covariance than assumed in the literature and causes a substantial leakage of Gaussian information. We decompose the covariance matrix into several contributions that provide an insight into its behavior for different biased tracers. We show that for realistic surveys, the covariance of power spectrum multipoles is already dominated by shot noise and super survey mode coupling in the weakly nonlinear regime. Both these effects can be accurately modeled analytically, making a perturbative treatment of the covariance very compelling. Our method allows for the covariance to be varied as a function of cosmology and bias parameters very efficiently, with survey geometry entering as fixed kernels that can be computed separately using fast fourier transforms (FFTs). We find excellent agreement between our analytic covariance and that estimated from BOSS DR12 Patchy mock catalogs in the whole range we tested, up to k =0.6 h /Mpc . This bodes well for application to future surveys such as DESI and Euclid.

Monthly Notices of the Royal Astronomical Society(12/2020)doi:10.1093/mnras/staa3019

abstract +abstract -

We present constraints on the emergence and evolution of passive galaxies with the empirical model EMERGE, which reproduces the evolution of stellar mass functions (SMFs), specific and cosmic star formation rates since $z$ ≍ 10, 'quenched' galaxy fractions, and correlation functions. At fixed halo mass, present-day passive galaxies are more massive than active galaxies, whereas at fixed stellar mass passive galaxies populate more massive haloes in agreement with observations. This effect naturally results from the shape and scatter of the stellar-to-halo mass relation. The stellar mass assembly of present-day passive galaxies is dominated by 'in situ' star formation below ∼3 × 10¹¹ M_⊙ and by merging and accretion of 'ex situ' formed stars at higher mass. The mass dependence is in tension with current cosmological simulations. Lower mass passive galaxies show extended star formation towards low redshift in agreement with IFU surveys. All passive galaxies have main progenitors on the 'main sequence of star formation' with the 'red sequence' appearing at $z$ ≍ 2. Above this redshift, over 95 per cent of the progenitors of passive galaxies are active. More than 90 per cent of $z$ ≍ 2 'main sequence' galaxies with m_* > 10¹⁰ M_⊙ evolve into present-day passive galaxies. Above redshift 6, more than 80 per cent of the observed SMFs above 10⁹ M_⊙ can be accounted for by progenitors of passive galaxies with m_* > 10¹⁰ M_⊙. This implies that high-redshift observations mainly probe the birth of present-day passive galaxies. EMERGE is available at github.com/bmoster/emerge.

CN-2

RU-D

abstract +abstract -

The Manfred Hirt Planet Spectrograph (MaHPS) — formerly also referred to as FOCES — is a high-resolution echelle spectrograph at the 2m telescope of the Wendelstein Observatory. One of its main scientific goals is the detection of planets at the few m/s level. To achieve such high precisions on a long-term scale, environmental stabilization of the instrument is required. The currently used temperature and pressure control systems are introduced and we present two different temperature control setups, with two and three actively controlled layers respectively. A series of measurements with an Astro Frequency Comb (AFC) as calibrator is shown to illustrate the system performance.

abstract +abstract -

The Manfred Hirt Planet Spectrograph - formerly operated under the name FOCES - started its regular scientific observation program in fall 2019 at the 2m telescope of the Wendelstein Observatory, operated by the University Observatory of the LMU Munich. We present the first radial velocity stability measurements of an astronomical target, the 51 Pegasi b exoplanet system, utilizing our Astro Frequency Comb (ACF) for wavelength calibration. For computing RV shifts from orderwisely extracted Echelle spectra we have developed a new software pipeline. In this proceeding we will introduce the most important features of our pipeline: wavelength calibration with simultaneously recorded spectra of the AFC, generation of spectral templates, and an optional fit or cross- correlation function (CCF) for the calculation of the relative RV signals. Finally, the performance of the pipeline real data is demonstrated.

Mon.Not.Roy.Astron.Soc.(11/2020)e-Print:2011.10237doi:10.1093/mnras/stab011

abstract +abstract -

We present a multifrequency study of the transient γ-ray source 4FGL J1544.3−0649, a blazar that exhibited a remarkable behaviour raising from the state of an anonymous mid-intensity radio source, never detected at high energies, to that of one of the brightest extreme blazars in the X-ray and γ-ray sky. Our analysis shows that the averaged γ-ray spectrum is well described by a power law with a photon index of 1.87±0.04, while the flux above 100 MeV is (8.0±0.9)× 10^−9 photon cm^−2 s^−1, which increases during the active state of the source. The X-ray flux and spectral slope are both highly variable, with the highest 2–10keV flux reaching (1.28±0.05)× 10^−10 erg cm^−2 s^−1. On several observations, the X-ray spectrum hardened to the point implying as SED peak moving to energies larger than 10keV. As in many extreme blazars the broad-band spectral energy distribution can be described by a hom*ogeneous one-zone synchrotron-self-Compton leptonic model. We briefly discuss the potential implications for high-energy multimessenger astrophysics in case the dual behaviour shown by 4FGL J1544.3−0649 does not represent an isolated case, but rather a manifestation of a so far unnoticed relatively common phenomenon.