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<jats:title>Abstract</jats:title> <jats:p>Vortices are readily produced by hydrodynamical instabilities, such as the Rossby wave instability, in protoplanetary disks. However, large-scale asymmetries indicative of dust-trapping vortices are uncommon in submillimeter continuum observations. One possible explanation is that vortices have short lifetimes. In this paper, we explore how radiative cooling can lead to vortex decay. Elliptical vortices in Keplerian disks go through adiabatic heating and cooling cycles. Radiative cooling modifies these cycles and generates baroclinicity that changes the potential vorticity of the vortex. We show that the net effect is typically a spin down, or decay, of the vortex for a subadiabatic radial stratification. We perform a series of two-dimensional shearing box simulations, varying the gas cooling (or relaxation) time, <jats:italic>t</jats:italic> <jats:sub>cool</jats:sub>, and initial vortex strength. We measure the vortex decay half-life, <jats:italic>t</jats:italic> <jats:sub>half</jats:sub>, and find that it can be roughly predicted by the timescale ratio <jats:italic>t</jats:italic> <jats:sub>cool</jats:sub>/<jats:italic>t</jats:italic> <jats:sub>turn</jats:sub>, where <jats:italic>t</jats:italic> <jats:sub>turn</jats:sub> is the vortex turnaround time. Decay is slow in both the isothermal (<jats:italic>t</jats:italic> <jats:sub>cool</jats:sub> ≪ <jats:italic>t</jats:italic> <jats:sub>turn</jats:sub>) and adiabatic (<jats:italic>t</jats:italic> <jats:sub>cool</jats:sub> ≫ <jats:italic>t</jats:italic> <jats:sub>turn</jats:sub>) limits; it is fastest when <jats:italic>t</jats:italic> <jats:sub>cool</jats:sub> ∼ 0.1 <jats:italic>t</jats:italic> <jats:sub>turn</jats:sub>, where <jats:italic>t</jats:italic> <jats:sub>half</jats:sub> is as short as ∼300 orbits. At tens of astronomical units where disk rings are typically found, <jats:italic>t</jats:italic> <jats:sub>turn</jats:sub> is likely much longer than <jats:italic>t</jats:italic> <jats:sub>cool</jats:sub>, potentially placing vortices in the fast decay regime.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In the past few years, new observations of neutron stars (NSs) and NS mergers have provided a wealth of data that allow one to constrain the equation of state (EOS) of nuclear matter at densities above nuclear saturation density. However, most observations were based on NSs with masses of about 1.4 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, probing densities up to ∼three to four times the nuclear saturation density. Even higher densities are probed inside massive NSs such as PSR J0740+6620. Very recently, new radio observations provided an update to the mass estimate for PSR J0740+6620, and X-ray observations by the NICER and XMM telescopes constrained its radius. Based on these new measurements, we revisit our previous nuclear physics multimessenger astrophysics constraints and derive updated constraints on the EOS describing the NS interior. By combining astrophysical observations of two radio pulsars, two NICER measurements, the two gravitational-wave detections GW170817 and GW190425, detailed modeling of the kilonova AT 2017gfo, and the gamma-ray burst GRB 170817A, we are able to estimate the radius of a typical 1.4 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> NS to be <jats:inline-formula> <jats:tex-math> <?CDATA ${11.94}_{-0.87}^{+0.76}\,\mathrm{km}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>11.94</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.87</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.76</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace width="0.25em" /> <mml:mi>km</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac19abieqn1.gif" xlink:type="simple" /> </jats:inline-formula> at 90% confidence. Our analysis allows us to revisit the upper bound on the maximum mass of NSs and disfavors the presence of a strong first-order phase transition from nuclear matter to exotic forms of matter, such as quark matter, inside NSs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present the delay time distribution (DTD) estimates of Type Ia supernovae (SNe Ia) using spatially resolved SN Ia host galaxy spectra from MUSE and MaNGA. By employing a grouping algorithm based on <jats:italic>k</jats:italic>-means and earth mover’s distances (EMDs), we separated the host galaxy stellar population age distributions (SPADs) into spatially distinct regions and used maximum likelihood method to constrain the DTD of SN Ia progenitors. When a power-law model of the form DTD(<jats:italic>t</jats:italic>) ∝ <jats:italic>t</jats:italic> <jats:sup> <jats:italic>s</jats:italic> </jats:sup>(<jats:italic>t</jats:italic> &gt; <jats:italic>τ</jats:italic>) is used, we find an SN rate decay slope <jats:inline-formula> <jats:tex-math> <?CDATA $s=-{1.41}_{-0.33}^{+0.32}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>s</mml:mi> <mml:mo>=</mml:mo> <mml:mo>−</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>1.41</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.33</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.32</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac178dieqn1.gif" xlink:type="simple" /> </jats:inline-formula> and a delay time <jats:inline-formula> <jats:tex-math> <?CDATA $\tau ={120}_{-83}^{+142}\mathrm{Myr}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>τ</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>120</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>83</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>142</mml:mn> </mml:mrow> </mml:msubsup> <mml:mi>Myr</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac178dieqn2.gif" xlink:type="simple" /> </jats:inline-formula>. Moreover, we tested other DTD models, such as a broken power-law model and a two-component power-law model, and found no statistically significant support for these alternative models.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Gas-giant planets, such as Jupiter, Saturn, and massive exoplanets, were formed via the gas accretion onto the solid cores, each with a mass of roughly 10 Earth masses. However, rapid radial migration due to disk–planet interaction prevents the formation of such massive cores via planetesimal accretion. Comparably rapid core growth via pebble accretion requires very massive protoplanetary disks because most pebbles fall into the central star. Although planetesimal formation, planetary migration, and gas-giant core formation have been studied with a lot of effort, the full evolution path from dust to planets is still uncertain. Here we report the result of full simulations for collisional evolution from dust to planets in a whole disk. Dust growth with realistic porosity allows the formation of icy planetesimals in the inner disk (≲10 au), while pebbles formed in the outer disk drift to the inner disk and there grow to planetesimals. The growth of those pebbles to planetesimals suppresses their radial drift and supplies small planetesimals sustainably in the vicinity of cores. This enables rapid formation of sufficiently massive planetary cores within 0.2–0.4 million years, prior to the planetary migration. Our models shows the first gas giants form at 2–7 au in rather common protoplanetary disks, in agreement with the exoplanet and solar systems.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present the results of 3 GHz radio continuum observations of 23 superluminous supernovae (SLSNe) and their host galaxies by using the Karl G. Jansky Very Large Array conducted 5–21 yr after the explosions. The sample consists of 15 Type I and 8 Type II SLSNe at <jats:italic>z</jats:italic> &lt; 0.3, providing one of the largest samples of SLSNe with late-time radio data. We detected radio emission from one SLSN (PTF10hgi) and five hosts with a significance of &gt;5<jats:italic>σ</jats:italic>. No time variability is found in late-time radio light curves of the radio-detected sources in a timescale of years except for PTF10hgi, whose variability is reported in a separate study. Comparison of star formation rates (SFRs) derived from the 3 GHz flux densities with those derived from SED modeling based on UV–NIR data shows that four hosts have an excess of radio SFRs, suggesting obscured star formation. Upper limits for undetected hosts and stacked results show that the majority of the SLSN hosts do not have a significant obscured star formation. By using the 3 GHz upper limits, we constrain the parameters for afterglows arising from interaction between initially off-axis jets and circumstellar medium (CSM). We found that the models with higher energies (<jats:italic>E</jats:italic> <jats:sub>iso</jats:sub> ≳ several × 10<jats:sup>53</jats:sup> erg) and CSM densities (<jats:italic>n</jats:italic> ≳ 0.01 cm<jats:sup>−3</jats:sup>) are excluded, but lower energies or CSM densities are not excluded with the current data. We also constrained the models of pulsar wind nebulae powered by a newly born magnetar for a subsample of SLSNe with model predictions in the literature.</jats:p>