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<jats:title>Abstract</jats:title> <jats:p>We present the final sample of the Exploration of Local VolumE Satellites (ELVES) survey, a survey of the dwarf satellites of a nearly volume-limited sample of Milky Way (MW)−like hosts in the Local Volume. Hosts are selected simply via a cut in luminosity (<jats:inline-formula> <jats:tex-math> <?CDATA ${M}_{{K}_{s}}\lt -22.1$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>K</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>s</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> </mml:msub> <mml:mo>&lt;</mml:mo> <mml:mo>−</mml:mo> <mml:mn>22.1</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac6fd7ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> mag) and distance (<jats:italic>D</jats:italic> &lt; 12 Mpc). We cataloged the satellites of 25 of the 31 such hosts, with another five taken from the literature. All hosts are surveyed out to at least 150 projected kpc ( ∼ <jats:italic>R</jats:italic> <jats:sub>vir</jats:sub>/2), with the majority surveyed to 300 kpc ( ∼ <jats:italic>R</jats:italic> <jats:sub>vir</jats:sub>). Satellites are detected using a consistent semiautomated algorithm specialized for low surface brightness dwarfs. As shown through extensive tests with injected galaxies, the catalogs are complete to <jats:italic>M</jats:italic> <jats:sub> <jats:italic>V</jats:italic> </jats:sub> ∼ −9 mag and <jats:italic>μ</jats:italic> <jats:sub>0,<jats:italic>V</jats:italic> </jats:sub> ∼ 26.5 mag arcsec<jats:sup>−2</jats:sup>. Candidates are confirmed to be real satellites through distance measurements including redshift, tip of the red giant branch, and surface brightness fluctuations. Across all 30 surveyed hosts, there are 338 confirmed satellites with <jats:italic>M</jats:italic> <jats:sub> <jats:italic>V</jats:italic> </jats:sub> &lt; −9 mag, with a further 106 candidates awaiting distance measurement. For the vast majority of these, we provide consistent multiband Sérsic photometry. We show that satellite abundance correlates with host mass, with the MW being quite typical among comparable systems, and that satellite quenched fraction rises steeply with decreasing satellite mass, mirroring the quenched fraction for the MW and M31. The ELVES survey represents a massive increase in the statistics of surveyed systems with known completeness, and the provided catalogs are a unique data set to explore various aspects of small-scale structure and dwarf galaxy evolution.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We execute a detailed spectral-timing study of Cygnus X-1 in the low/hard, intermediate, and high/soft states with observations from the Hard X-ray Modulation Telescope. The broadband energy spectra fit well with the “truncated disk model”: the inner boundary of the accretion disk stays within ∼10 <jats:italic>R</jats:italic> <jats:sub>g</jats:sub> and moves inward as the source softens. Through studying the power density spectrum, rms, and Fourier frequency component resolved spectroscopy, we find that the X-ray variations are generated in two different regions for each state. We discover that the major contribution to the X-ray variation is from the hot corona rather than the accretion disk. We suggest a scenario with different coronal geometry for each state based on the truncated disk geometry in which the corona envelops the disk to form a sandwich geometry in the low/hard state, and then gradually moves away from the disk in a direction perpendicular to the disk until it forms a jet-like geometry in the high/soft state.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Halos of similar mass and redshift exhibit a large degree of variability in their differential properties, such as dark matter, hot gas, and stellar mass density profiles. This variability is an indicator of diversity in the formation history of these dark matter halos that is reflected in the coupling of scatters about the mean relations. In this work, we show that the strength of this coupling depends on the scale at which halo profiles are measured. By analyzing the outputs of the IllustrisTNG hydrodynamical cosmological simulations, we report the radial- and mass-dependent couplings between the dark matter, hot gas, and stellar mass radial density profiles utilizing the population diversity in dark matter halos. We find that for the same mass halos, the scatters in the density of baryons and dark matter are strongly coupled at large scales (<jats:italic>r</jats:italic> &gt; <jats:italic>R</jats:italic> <jats:sub>200</jats:sub>), but the coupling between gas and dark matter density profiles fades near the core of halos (<jats:italic>r</jats:italic> &lt; 0.3<jats:italic>R</jats:italic> <jats:sub>200</jats:sub>). We then show that the correlation between halo profile and integrated quantities induces a radius-dependent additive bias in the profile observables of halos when halos are selected on properties other than their mass. We discuss the impact of this effect on cluster abundance and cross-correlation cosmology with multiwavelength cosmological surveys.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>It is reasonable to assume that the structure of a planet and the interior distribution of its components are determined by its formation history. We thus follow the growth of a planet from a small embryo through its subsequent evolution. We estimate the accretion rate range based on a protoplanetary disk model at a large-enough distance from the central star for water ice to be a major component. We assume the accreted material to be a mixture of silicate rock and ice, with no H–He envelope, as the accretion timescale is much longer than the time required for the nebular gas to dissipate. We adopt a thermal evolution model that includes accretional heating, radioactive energy release, and separation of ice and rock. Taking the Safronov parameter and the ice-to-rock ratio as free parameters, we compute growth and evolutionary sequences for different parameter combinations, for 4.6 Gyr. We find the final structure to depend significantly on both parameters. Low initial ice-to-rock ratios and high accretion rates, each resulting in an increased heating rate, lead to the formation of extended rocky cores, while the opposite conditions leave the composition almost unchanged and result in relatively low internal temperatures. When rocky cores form, the ice-rich outer mantles still contain rock mixed with the ice. We find that a considerable fraction of the ice evaporates upon accretion, depending on parameters, and assume it is lost, thus the final surface composition and bulk density of the planet do not necessarily reflect the protoplanetary disk composition.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The ongoing monitoring of the Galactic center and Sgr A*, the central supermassive black hole, produces surprising and unexpected findings. This goes hand in hand with the technical evolution of ground- and space-based telescopes and instruments, but also with the progression of image filter techniques such as the Lucy–Richardson algorithm. As we continue to trace the members of the S cluster close to Sgr A* on their expected trajectory around the supermassive black hole, we present the finding of a new stellar source, which we call S4716. The newly found star orbits Sgr A* in about 4.0 yr and can be detected with NIRC2 (Keck), OSIRIS (Keck), SINFONI (VLT), NACO (VLT), and GRAVITY (VLTI). With a periapse distance of about 100 au, S4716 shows an equivalent distance toward Sgr A* as S4711. These fast-moving stars undergo a similar dynamical evolution, since S4711–S4716 share comparable orbital properties. We will furthermore draw a connection between the recent finding of a new faint star called S300 and the data presented here. Additionally, we observed a blend-star event with S4716 and another newly identified S star S148 in 2017.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Using a MeerKAT observation of the galaxy cluster A3562 (a member of the Shapley supercluster), we have discovered a narrow, long and straight, very faint radio filament, which branches out at a straight angle from the tail of a radio galaxy located in projection near the core of the cluster. The radio filament spans 200 kpc and aligns with a sloshing cold front seen in the X-rays, staying inside the front in projection. The radio spectral index along the filament appears uniform (within large uncertainties) at <jats:italic>α</jats:italic> ≃ −1.5. We propose that the radio galaxy is located outside the cold front but dips its tail under the front. The tangential wind that blows there may stretch the radio plasma from the radio galaxy into a filamentary structure. Some reacceleration is needed in this scenario to keep the radio spectrum uniform. Alternatively, the cosmic-ray electrons from that spot in the tail can spread along the cluster magnetic field lines, straightened by that same tangential flow, via anomalously fast diffusion. Our radio filament can provide constraints on this process. We also uncover a compact radio source at the brightest cluster galaxy that is 2–3 orders of magnitude less luminous than those in typical cluster central galaxies—probably an example of a brightest cluster galaxy starved of accretion fuel by gas sloshing.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present an analysis of physical properties of 34 [O <jats:sc>iii</jats:sc>] emission-line galaxies (ELGs) at <jats:italic>z</jats:italic> = 3.254 ± 0.029 in the Extended Chandra Deep Field South (ECDFS). These ELGs are selected from deep narrow H<jats:sub>2</jats:sub>S(1) and broad <jats:italic>K</jats:italic> <jats:italic> <jats:sub>s</jats:sub> </jats:italic> imaging of 383 arcmin<jats:sup>2</jats:sup> obtained with CFHT/WIRCam. We construct spectral energy distributions (SEDs) from <jats:italic>U</jats:italic> to <jats:italic>K</jats:italic> <jats:italic> <jats:sub>s</jats:sub> </jats:italic> to derive the physical properties of ELGs. These [O <jats:sc>iii</jats:sc>] ELGs are identified as starburst galaxies with strong [O <jats:sc>iii</jats:sc>] lines of <jats:italic>L</jats:italic> <jats:sub>O<jats:sc>III</jats:sc> </jats:sub> ∼ 10<jats:sup>42.6</jats:sup>–10<jats:sup>44.2</jats:sup> erg s<jats:sup>−1</jats:sup> and have stellar masses of <jats:italic>M</jats:italic> <jats:sub>*</jats:sub> ∼ 10<jats:sup>9.0</jats:sup>–10<jats:sup>10.6</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> and star formation rates of ∼10–210 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup>. Our results show that 24% of our sample galaxies are dusty with <jats:italic>A</jats:italic> <jats:italic> <jats:sub>V</jats:sub> </jats:italic> &gt; 1 mag and EW([O <jats:sc>iii</jats:sc>])<jats:sub>rest</jats:sub> ∼ 70–500 Å, which are often missed in optically selected [O <jats:sc>iii</jats:sc>] ELG samples. Their rest-frame UV and optical morphologies from HST/ACS and HST/WFC3 deep imaging reveal that these [O <jats:sc>iii</jats:sc>] ELGs are mostly multiple-component systems (likely mergers) or compact. And 20% of them are nearly invisible in the rest-frame UV owing to heavy dust attenuation. Interestingly, we find that our sample ELGs reside in an overdensity consisting of two components: one southeast (SE) with an overdensity factor of <jats:italic>δ</jats:italic> <jats:sub>gal</jats:sub> ∼ 41 over a volume of 13<jats:sup>3</jats:sup> cMpc<jats:sup>3</jats:sup>, and the other northwest (NW) with <jats:italic>δ</jats:italic> <jats:sub>gal</jats:sub> ∼ 38 over a volume of 10<jats:sup>3</jats:sup> cMpc<jats:sup>3</jats:sup>. The two overdense substructures are expected to be virialized at <jats:italic>z</jats:italic> = 0 with a total mass of ∼ 1.1 × 10<jats:sup>15</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> and ∼ 4.8 × 10<jats:sup>14</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> and probably merge into a Coma-like galaxy cluster.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>One <jats:italic>strong</jats:italic> magnetic cloud (MC) with a magnetic field magnitude reaching ∼40 nT at 1 au during 2012 June 16–17 is examined in association with a preexisting magnetic flux rope (MFR) identified on the Sun. The MC is characterized by a quasi-three-dimensional (3D) flux rope model based on in situ measurements from the Wind spacecraft. The contents of the magnetic flux and other parameters are quantified. In addition, a correlative study with the corresponding measurements of the same structure crossed by the Venus Express (VEX) spacecraft at a heliocentric distance of 0.7 au and with an angular separation of ∼6° in longitude is performed to validate the MC modeling results. The spatial variation between the Wind and VEX magnetic field measurements is attributed to the 3D configuration of the structure appearing as a knotted bundle of flux. A comparison of the magnetic flux contents between the MC and the preexisting MFR on the Sun indicates that the 3D reconnection process accompanying an M1.9 flare may correspond to the magnetic reconnection between the field lines of the preexisting MFR rooted in the opposite polarity footpoints. Such a process reduces the amount of the axial magnetic flux in the erupted flux rope, by approximately 50%, in this case.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>At cosmic dawn, the 21 cm signal from intergalactic hydrogen was driven by Ly-<jats:italic>α</jats:italic> photons from some of the earliest stars, producing a spatial pattern that reflected the distribution of galaxies at that time. Due to the large foreground, it is thought that at around redshift 20 it is only observationally feasible to detect 21 cm fluctuations statistically, yielding a limited indirect probe of early galaxies. Here, we show that 21 cm images at cosmic dawn should actually be dominated by large (tens of comoving megaparsecs) high-contrast bubbles surrounding individual galaxies. We demonstrate this using a substantially upgraded seminumerical simulation code that realistically captures the formation and 21 cm effects of the small galaxies expected during this era. Small number statistics associated with the rarity of early galaxies, combined with the multiple scattering of photons in the blue wing of the Ly-<jats:italic>α</jats:italic> line, create the large bubbles, and also enhance the 21 cm power spectrum by a factor of 2–7 and add to it a feature that measures the typical brightness of galaxies. These various signatures of discrete early galaxies are potentially detectable with planned experiments, such as the Square Kilometer Array and the Hydrogen Epoch of Reionization Array, even if the early stars prove to be formed in dark matter halos with masses as low as 10<jats:sup>8</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, 10,000 times smaller than the Milky Way halo.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present 3D hydrodynamical models of the evolution of superbubbles powered by stellar winds and supernovae from young coeval massive star clusters within low-metallicity (<jats:italic>Z</jats:italic> = 0.02 <jats:italic>Z</jats:italic> <jats:sub>⊙</jats:sub>), clumpy molecular clouds. We explore the initial stages of the superbubble evolution, including the occurrence of pair-instability and core-collapse supernovae. Our aim is to study the occurrence of dust grain growth within orbiting dusty clumps, and in the superbubble’s swept-up supershell. We also aim to address the survival of dust grains produced by sequential supernovae. The model accounts for the star cluster gravitational potential and self-gravity of the parent cloud. It also considers radiative cooling (including that induced by dust) and a state-of-the-art population synthesis model for the coeval cluster. As shown before, a superbubble embedded into a clumpy medium becomes highly distorted, expanding mostly due to the hot gas streaming through low-density channels. Our results indicate that in the case of massive (∼10<jats:sup>7</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>) molecular clouds, hosting a super star cluster (∼5.6 × 10<jats:sup>5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>), grain growth increments the dust mass at a rate ∼4.8 × 10<jats:sup>−5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup> during the first 2.5 Myr of the superbubble’s evolution, while the net contribution of pair-instability and core-collapse supernovae to the superbubble’s dust budget is ∼1200 <jats:italic>M</jats:italic> <jats:sub>⊙ </jats:sub>(<jats:italic>M</jats:italic> <jats:sub>SC</jats:sub>/5.6 × 10<jats:sup>5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>), where <jats:italic>M</jats:italic> <jats:sub>SC</jats:sub> is the stellar mass of the starburst. Therefore, dust grain growth and dust injection by supernovae lead to the creation of, without invoking a top-heavy initial mass function, massive amounts of dust within low-metallicity star-forming molecular clouds, in accordance with the large dust mass present in galaxies soon after the onset of cosmic reionization.</jats:p>