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<jats:title>Abstract</jats:title> <jats:p>Reionization is an inhomogeneous process, thought to begin in small ionized bubbles of the intergalactic medium (IGM) around overdense regions of galaxies. Recent Ly<jats:italic>α</jats:italic> studies during the epoch of reionization show evidence that ionized bubbles formed earlier around brighter galaxies, suggesting higher IGM transmission of Ly<jats:italic>α</jats:italic> from these galaxies. We investigate this problem using IR slitless spectroscopy from the Hubble Space Telescope (HST) Wide-Field Camera 3 (WFC3) G102 grism observations of 148 galaxies selected via photometric redshifts at 6.0 &lt; <jats:italic>z</jats:italic> &lt; 8.2. These galaxies have spectra extracted from the CANDELS Ly<jats:italic>α</jats:italic> Emission at Reionization (CLEAR) survey. We combine the CLEAR data for 275 galaxies with the Keck Deep Imaging Multi-Object Spectrograph and MOSFIRE data set from the Texas Spectroscopic Search for Ly<jats:italic>α</jats:italic> Emission at the End of Reionization Survey. We constrain the Ly<jats:italic>α</jats:italic> equivalent width (EW) distribution at 6.0 &lt; <jats:italic>z</jats:italic> &lt; 8.2, which is described by an exponential form, <jats:inline-formula> <jats:tex-math> <?CDATA ${dN}/d\mathrm{EW}\propto \exp (-\mathrm{EW})/{W}_{0}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi mathvariant="italic">dN</mml:mi> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:mi>d</mml:mi> <mml:mi>EW</mml:mi> <mml:mo>∝</mml:mo> <mml:mi>exp</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:mo>−</mml:mo> <mml:mi>EW</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:msub> <mml:mrow> <mml:mi>W</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> </mml:msub> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac6fe7ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, with the characteristic <jats:italic>e</jats:italic>-folding scale width (<jats:italic>W</jats:italic> <jats:sub>0</jats:sub>). We confirm a significant drop in the Ly<jats:italic>α</jats:italic> strength (i.e., <jats:italic>W</jats:italic> <jats:sub>0</jats:sub>) at <jats:italic>z</jats:italic> &gt; 6. Furthermore, we compare the redshift evolution of <jats:italic>W</jats:italic> <jats:sub>0</jats:sub> between galaxies at different UV luminosities. UV-bright (<jats:italic>M</jats:italic> <jats:sub>UV</jats:sub> &lt; −21 [i.e., <jats:italic>L</jats:italic> <jats:sub>UV</jats:sub> &gt; <jats:italic>L</jats:italic>*]) galaxies show weaker evolution with a decrease of 0.4 ( ± 0.2) dex in <jats:italic>W</jats:italic> <jats:sub>0</jats:sub> at <jats:italic>z</jats:italic> &gt; 6, while UV-faint (<jats:italic>M</jats:italic> <jats:sub>UV</jats:sub> &gt; −21 [<jats:italic>L</jats:italic> <jats:sub>UV</jats:sub> &lt; <jats:italic>L</jats:italic>*]) galaxies exhibit a significant drop of 0.7–0.8 (±0.2) dex in <jats:italic>W</jats:italic> <jats:sub>0</jats:sub> from <jats:italic>z</jats:italic> &lt; 6 to <jats:italic>z</jats:italic> &gt; 6. If the change in <jats:italic>W</jats:italic> <jats:sub>0</jats:sub> is proportional to the change in the IGM transmission for Ly<jats:italic>α</jats:italic> photons, then this is evidence that the transmission is “boosted” around UV-brighter galaxies, suggesting that reionization proceeds faster in regions around such galaxies.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We report a NOrthern Extended Millimeter Array (NOEMA) and Atacama Large Millimeter/submillimeter Array search for redshifted CO emission from the galaxies associated with seven high-metallicity ([M/H] ≥ −1.03) damped Ly<jats:italic>α</jats:italic> absorbers (DLAs) at <jats:italic>z</jats:italic> ≈ 1.64–2.51. Our observations yielded one new detection of CO(3–2) emission from a galaxy at <jats:italic>z</jats:italic> = 2.4604 using NOEMA, associated with the <jats:italic>z</jats:italic> = 2.4628 DLA toward QSO B0201+365. Including previous searches, our search results in detection rates of CO emission of <jats:inline-formula> <jats:tex-math> <?CDATA $\approx {56}_{-24}^{+38}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>≈</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>56</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>24</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>38</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b2cieqn1.gif" xlink:type="simple" /> </jats:inline-formula>% and <jats:inline-formula> <jats:tex-math> <?CDATA $\approx {11}_{-9}^{+26}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>≈</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>11</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>9</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>26</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b2cieqn2.gif" xlink:type="simple" /> </jats:inline-formula>%, respectively, in the fields of DLAs with [M/H] &gt; −0.3 and [M/H] &lt; −0.3. Further, the H<jats:sc>i</jats:sc>–selected galaxies associated with five DLAs with [M/H] &gt; −0.3 all have high molecular gas masses, ≳5 × 10<jats:sup>10</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>. This indicates that the highest-metallicity DLAs at <jats:italic>z</jats:italic> ≈ 2 are associated with the most massive galaxies. The newly identified <jats:italic>z</jats:italic> ≈ 2.4604 H<jats:sc>i</jats:sc>–selected galaxy, DLA0201+365g, has an impact parameter of ≈7 kpc to the QSO sightline, and an implied molecular gas mass of (5.04 ± 0.78) × 10<jats:sup>10</jats:sup> × (<jats:italic>α</jats:italic> <jats:sub>CO</jats:sub>/4.36) × (<jats:italic>r</jats:italic> <jats:sub>31</jats:sub>/0.55) <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>. Archival Hubble Space Telescope Wide Field and Planetary Camera 2 imaging covering the rest-frame near-ultraviolet (NUV) and far-ultraviolet (FUV) emission from this galaxy yield nondetections of rest-frame NUV and FUV emission, and a 5<jats:italic>σ</jats:italic> upper limit of 2.3 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup> on the unobscured star formation rate (SFR). The low NUV-based SFR estimate, despite the very high molecular gas mass, indicates that DLA0201+365g either is a very dusty galaxy, or has a molecular gas depletion time that is around 2 orders of magnitude larger than that of star-forming galaxies at similar redshifts.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We analyze spatially resolved and co-added SDSS-IV MaNGA spectra with signal-to-noise ratio ∼100 from 2200 passive central galaxies (<jats:italic>z</jats:italic> ∼ 0.05) to understand how central galaxy assembly depends on stellar mass (<jats:italic>M</jats:italic> <jats:sub>*</jats:sub>) and halo mass (<jats:italic>M</jats:italic> <jats:sub> <jats:italic>h</jats:italic> </jats:sub>). We control for systematic errors in <jats:italic>M</jats:italic> <jats:sub> <jats:italic>h</jats:italic> </jats:sub> by employing a new group catalog from Tinker and the widely used Yang et al. catalog. At fixed <jats:italic>M</jats:italic> <jats:sub>*</jats:sub>, the strengths of several stellar absorption features vary systematically with <jats:italic>M</jats:italic> <jats:sub> <jats:italic>h</jats:italic> </jats:sub>. Completely model-free, this is one of the first indications that the stellar populations of centrals with identical <jats:italic>M</jats:italic> <jats:sub>*</jats:sub> are affected by the properties of their host halos. To interpret these variations, we applied full spectral fitting with the code <jats:monospace>alf</jats:monospace>. At fixed <jats:italic>M</jats:italic> <jats:sub>*</jats:sub>, centrals in more massive halos are older, show lower [Fe/H], and have higher [Mg/Fe] with 3.5<jats:italic>σ</jats:italic> confidence. We conclude that halos not only dictate how much <jats:italic>M</jats:italic> <jats:sub>*</jats:sub> galaxies assemble but also modulate their chemical enrichment histories. Turning to our analysis at fixed <jats:italic>M</jats:italic> <jats:sub> <jats:italic>h</jats:italic> </jats:sub>, high-<jats:italic>M</jats:italic> <jats:sub>*</jats:sub> centrals are older, show lower [Fe/H], and have higher [Mg/Fe] for <jats:italic>M</jats:italic> <jats:sub> <jats:italic>h</jats:italic> </jats:sub> &gt; 10<jats:sup>12</jats:sup> <jats:italic> h</jats:italic> <jats:sup>−1</jats:sup> <jats:italic> M</jats:italic> <jats:sub>⊙</jats:sub> with confidence &gt;4<jats:italic>σ</jats:italic>. While massive passive galaxies are thought to form early and rapidly, our results are among the first to distinguish these trends at fixed <jats:italic>M</jats:italic> <jats:sub> <jats:italic>h</jats:italic> </jats:sub>. They suggest that high-<jats:italic>M</jats:italic> <jats:sub>*</jats:sub> centrals experienced unique <jats:italic>early</jats:italic> formation histories, either through enhanced collapse and gas fueling or because their halos were early forming and highly concentrated, a possible signal of galaxy assembly bias.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>This paper investigates the impact of dust size distribution on magnetic resistivity. In particular, we focus on its impact when the maximum dust size significantly increases from a submicron level. The first half of the paper describes our calculation method for magnetic resistivity based on the model of Draine &amp; Sutin and shows that the method reproduces the results of more realistic chemical reaction network calculations reasonably well. Then, we describe the results of the resistivity calculations for dust distributions with large maximum dust grains. Our results show that resistivity tends to decrease with dust growth, which is particularly true when the dust size power exponent <jats:italic>q</jats:italic> is <jats:italic>q</jats:italic> = 2.5. On the other hand, the decrease is less pronounced when the dust size power exponent <jats:italic>q</jats:italic> is <jats:italic>q</jats:italic> = 3.5, i.e., when the small dust is also responsible for the dust cross section. Our results suggest that detailed dust coagulation and fragmentation processes play a vital role in the magnetic resistivities in protostar formation.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In supernovae (SNe), where the light curves show evidence of strong and early interaction between the ejecta and the circumstellar matter (CSM), the formation of new dust is estimated to take place in a dense shell of gas between the forward shock (FS) and the reverse shock (RS). For the first time, in this study the mechanism of dust formation in this dense shell is modeled. A set of nine cases, considering variations of the ejecta mass and the pre-explosion mass-loss rates, is considered, accounting for the diverse nature of interactions reported in such SNe. For a single main-sequence mass, the variation of ejecta mass was manifested as a variation of the H-shell mass of the star, lost due to pre-explosion mass loss. We find that the dust masses in the dense shell range between 10<jats:sup>−3</jats:sup> and 0.8 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, composed of O-rich and C-rich grains, whose relative proportions are determined by the nature of interaction. Dust formation in the post-shock gas is characterized by a gradual production rate, mostly ranging from 10<jats:sup>−6</jats:sup> to 10<jats:sup>−3</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> day<jats:sup>−1</jats:sup>, which may continue for a decade, post-explosion. A higher mass-loss rate leads to a larger mass of dust, while a smaller ejecta mass (smaller leftover H shell) increases the efficiency of dust production in such SNe. Dust formed behind the RS, as in our calculations, is not subject to destruction by either the FS or RS and is thus likely to survive in a larger proportion than dust formed in the ejecta.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Kiloparsec-scale triple active galactic nuclei (AGNs), potential precursors of gravitationally bound triple massive black holes (MBHs), are rarely seen objects and believed to play an important role in the evolution of MBHs and their host galaxies. In this work we present a multiband (3.0, 6.0, 10.0, and 15.0 GHz), high-resolution radio imaging of the triple AGN candidate, SDSS J0849+1114, using the Very Large Array. Two of the three nuclei (A and C) are detected at 3.0, 6.0, and 15 GHz for the first time, both exhibiting a steep spectrum over 3–15 GHz (with a spectral index −0.90 ± 0.05 and −1.03 ± 0.04) consistent with a synchrotron origin. Nucleus A, the strongest nucleus among the three, shows a double-sided jet, with the jet orientation changing by ∼20° between its inner 1″ and the outer 5.″5 (8.1 kpc) components, which may be explained as the MBH’s angular momentum having been altered by merger-enhanced accretion. Nucleus C also shows a two-sided jet, with the western jet inflating into a radio lobe with an extent of 1.″5 (2.2 kpc). The internal energy of the radio lobe is estimated to be 5.0 × 10<jats:sup>55</jats:sup> erg, for an equipartition magnetic field strength of ∼160 <jats:italic>μ</jats:italic>G. No significant radio emission is detected at all four frequencies for nucleus B, yielding an upper limit of 15, 15, 15, and 18 <jats:italic>μ</jats:italic>Jy beam<jats:sup>−1</jats:sup> at 3.0, 6.0, 10.0, and 15.0 GHz, based on which we constrain the star formation rate in nucleus B to be ≲0.4 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup>.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present Atacama Large Millimeter/submillimeter Array data on the 3 mm continuum emission, CO isotopologues (<jats:sup>12</jats:sup>CO, <jats:sup>13</jats:sup>CO, and C<jats:sup>18</jats:sup>O), and high-density molecular tracers (HCN, HCO<jats:sup>+</jats:sup>, HNC, HNCO, CS, CN, and CH<jats:sub>3</jats:sub>OH) in NGC 4526. These data enable a detailed study of the physical properties of the molecular gas in a longtime resident of the Virgo Cluster; comparisons to more commonly studied spiral galaxies offer intriguing hints into the processing of molecular gas in the cluster environment. Many molecular line ratios in NGC 4526, along with our inferred abundances and CO/H<jats:sub>2</jats:sub> conversion factors, are similar to those found in nearby spirals. One striking exception is the very low observed <jats:sup>12</jats:sup>CO/<jats:sup>13</jats:sup>CO(1−0) line ratio, 3.4 ± 0.3, which is unusually low for spirals though not for Virgo Cluster early-type galaxies. We carry out radiative transfer modeling of the CO isotopologues with some archival (2−1) data, and we use Bayesian analysis with Markov Chain Monte Carlo techniques to infer the physical properties of the CO-emitting gas. We find surprisingly low [<jats:sup>12</jats:sup>CO/<jats:sup>13</jats:sup>CO] abundance ratios of <jats:inline-formula> <jats:tex-math> <?CDATA ${7.8}_{-1.5}^{+2.7}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>7.8</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1.5</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>2.7</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7149ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> and <jats:inline-formula> <jats:tex-math> <?CDATA ${6.5}_{-1.3}^{+3.0}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>6.5</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1.3</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>3.0</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7149ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> at radii of 0.4 kpc and 1 kpc. The emission from the high-density tracers HCN, HCO<jats:sup>+</jats:sup>, HNC, CS, and CN is also relatively bright, and CN is unusually optically thick in the inner parts of NGC 4526. These features hint that processing in the cluster environment may have removed much of the galaxy’s relatively diffuse, optically thinner molecular gas along with its atomic gas. Angular momentum transfer to the surrounding intracluster medium may also have caused contraction of the disk, magnifying radial gradients such as we find in [<jats:sup>13</jats:sup>CO/C<jats:sup>18</jats:sup>O]. More detailed chemical evolution modeling would be interesting in order to explore whether the unusual [<jats:sup>12</jats:sup>CO/<jats:sup>13</jats:sup>CO] abundance ratio is entirely an environmental effect or whether it also reflects the relatively old stellar population in this early-type galaxy.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Using full Boltzmann neutrino transport, we performed 2D core-collapse supernova simulations in axisymmetry for two progenitor models with 11.2 and 15.0<jats:italic> M</jats:italic> <jats:sub>⊙</jats:sub>, both rotational and nonrotational. We employed the results obtained in the early post-bounce phase (<jats:italic>t</jats:italic> ≲ 20 ms) to assess performance under rapid rotation of some closure relations commonly employed in the truncated moment method. We first made a comparison in 1D under spherical symmetry, though, of the Eddington factor <jats:italic>p</jats:italic> defined in the fluid rest frame (FR). We confirmed that the maximum entropy closure for the Fermionic distribution (MEFD) performs better than others near the proto–neutron star surface, where <jats:italic>p</jats:italic> &lt; 1/3 occurs, but does not work well even in 1D when the phase-space occupancy satisfies <jats:italic>e</jats:italic> &lt; 0.5 together with <jats:italic>p</jats:italic> &lt; 1/3, the condition known to be not represented by MEFD. For the 2D models with the rapid rotation, we employed the principal-axis analysis of the Eddington tensor. We paid particular attention to the direction of the longest principal axis. We observed in FR that it is aligned neither with the radial direction nor with the neutrino flux in 2D, particularly so in convective and/or rapidly rotating regions, the fact not accommodated in the moment method. We repeated the same analysis in the laboratory frame and found again that the direction of the longest principal axis is not well reproduced by MEFD because the interpolation between the optically thick and thin limits is not very accurate in this frame.</jats:p>