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<jats:title>Abstract</jats:title> <jats:p>M54 is a prototype for a globular cluster embedded in a dark matter halo. Gaia Early Data Release 3 photometry and proper motions separate the old, metal-poor stars from the more metal-rich and younger dwarf galaxy stars. The metal-poor stars dominate the inner 50 pc, with a velocity dispersion profile that declines to a minimum around 30 pc then rises back to nearly the central velocity dispersion, as expected for a globular cluster at the center of a cold dark matter (CDM) cosmology dark matter halo. The Jeans equation mass analysis of the three separate stellar populations gives consistent masses that rise approximately linearly with radius to 1 kpc. These data are compatible with an infalling CDM dark matter halo reduced to ≃3 × 10<jats:sup>8</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> at the 50 kpc apocenter 2.3 Gyr ago, with a central globular cluster surrounded by the remnant of a dwarf galaxy. Tides gradually remove material beyond 1 kpc but have little effect on the stars and dark matter within 300 pc of the center. M54 appears to be a “transitional” system between globular clusters with and without local dark halos whose evolution within the galaxy depends on the time of accretion and orbital pericenter.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present the third discovery from the COol Companions ON Ultrawide orbiTS (COCONUTS) program, the COCONUTS-3 system, composed of the young M5 primary star UCAC4 374−046899 and the very red L6 dwarf WISEA J081322.19−152203.2. These two objects have a projected separation of <jats:inline-formula> <jats:tex-math> <?CDATA $61^{\prime\prime} $?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>61</mml:mn> <mml:mo accent="false">′</mml:mo> <mml:mo accent="false">′</mml:mo> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ce9ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> (1891 au) and are physically associated given their common proper motions and estimated distances. The primary star, COCONUTS-3A, has a mass of 0.123 ± 0.006 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, and we estimate its age as 100 Myr to 1 Gyr based on its stellar activity (via H<jats:italic>α</jats:italic> and X-ray emission), kinematics, and spectrophotometric properties. We derive its bulk metallicity as 0.21 ± 0.07 dex using empirical calibrations established by older and higher-gravity M dwarfs and find that this [Fe/H] could be slightly underestimated according to PHOENIX models given COCONUTS-3A’s younger age. The companion, COCONUTS-3B, has a near-infrared spectral type of L6 ± 1 <jats:sc>int-g</jats:sc>, and we infer physical properties of <jats:italic>T</jats:italic> <jats:sub>eff</jats:sub> = <jats:inline-formula> <jats:tex-math> <?CDATA ${1362}_{-73}^{+48}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>1362</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>73</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>48</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ce9ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> K, <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{log}(g)$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>log</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:mi>g</mml:mi> <mml:mo stretchy="false">)</mml:mo> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ce9ieqn3.gif" xlink:type="simple" /> </jats:inline-formula> = <jats:inline-formula> <jats:tex-math> <?CDATA ${4.96}_{-0.34}^{+0.15}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>4.96</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.34</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.15</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ce9ieqn4.gif" xlink:type="simple" /> </jats:inline-formula> dex, <jats:inline-formula> <jats:tex-math> <?CDATA $R\,=\,{1.03}_{-0.06}^{+0.12}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>R</mml:mi> <mml:mspace width="0.50em" /> <mml:mo>=</mml:mo> <mml:mspace width="0.50em" /> <mml:msubsup> <mml:mrow> <mml:mn>1.03</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.06</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.12</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ce9ieqn5.gif" xlink:type="simple" /> </jats:inline-formula> <jats:italic>R</jats:italic> <jats:sub>Jup</jats:sub>, and <jats:inline-formula> <jats:tex-math> <?CDATA $M\,=\,{39}_{-18}^{+11}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>M</mml:mi> <mml:mspace width="0.50em" /> <mml:mo>=</mml:mo> <mml:mspace width="0.50em" /> <mml:msubsup> <mml:mrow> <mml:mn>39</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>18</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>11</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ce9ieqn6.gif" xlink:type="simple" /> </jats:inline-formula> <jats:italic>M</jats:italic> <jats:sub>Jup</jats:sub> using its bolometric luminosity, its host star’s age, and hot-start evolution models. We construct cloudy atmospheric model spectra at the evolution-based physical parameters and compare them to COCONUTS-3B’s spectrophotometry. We find that this companion possesses ample condensate clouds in its photosphere (<jats:italic>f</jats:italic> <jats:sub>sed</jats:sub> = 1) with the data–model discrepancies likely due to the models using an older version of the opacity database. Compared to field-age L6 dwarfs, COCONUTS-3B has fainter absolute magnitudes and a 120 K cooler <jats:italic>T</jats:italic> <jats:sub>eff</jats:sub>. Also, the <jats:italic>J</jats:italic> − <jats:italic>K</jats:italic> color of this companion is among the reddest for ultracool benchmarks with ages older than a few hundred megayears. COCONUTS-3 likely formed in the same fashion as stellar binaries given the companion-to-host mass ratio of 0.3 and represents a valuable benchmark to quantify the systematics of substellar model atmospheres.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The next generation of wide-field cosmic microwave background (CMB) surveys are uniquely poised to open a new window into time-domain astronomy in the millimeter band. Here, we explore the discovery phase space for extragalactic transients with near-term and future CMB experiments to characterize the expected population. We use existing millimeter-band light curves of known transients (gamma-ray bursts, tidal disruption events, fast blue optical transients (FBOTs), neutron star mergers) and theoretical models, in conjunction with known and estimated volumetric rates. Using Monte Carlo simulations of various CMB survey designs (area, cadence, depth, duration) we estimate the detection rates and the resulting light-curve characteristics. We find that existing and near-term surveys will find tens to hundreds of long-duration gamma-ray bursts (LGRBs), driven primarily by detections of the reverse shock emission, and including off-axis LGRBs. Next-generation experiments (CMB-S4, CMB-HD) will find tens of FBOTs in the nearby universe and will detect a few tidal disruption events. CMB-HD will additionally detect a small number of short gamma-ray bursts, where these will be discovered within the detection volume of next-generation gravitational wave experiments like the Cosmic Explorer.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Spatially extended halos of H <jats:sc>i</jats:sc> Ly<jats:italic>α</jats:italic> emission are now ubiquitously found around high-redshift star-forming galaxies. But our understanding of the nature and powering mechanisms of these halos is still hampered by the complex radiative transfer effects of the Ly<jats:italic>α</jats:italic> line and limited angular resolution. In this paper, we present resolved Multi Unit Spectroscopic Explorer (MUSE) observations of SGAS J122651.3+215220, a strongly lensed pair of <jats:italic>L</jats:italic>* galaxies at <jats:italic>z</jats:italic> = 2.92 embedded in a Ly<jats:italic>α</jats:italic> halo of <jats:italic>L</jats:italic> <jats:sub>Ly<jats:italic>α</jats:italic> </jats:sub> = (6.2 ± 1.3) × 10<jats:sup>42</jats:sup> erg s<jats:sup>−1</jats:sup>. Globally, the system shows a line profile that is markedly asymmetric and redshifted, but its width and peak shift vary significantly across the halo. By fitting the spatially binned Ly<jats:italic>α</jats:italic> spectra with a collection of radiative transfer galactic wind models, we infer a mean outflow expansion velocity of ≈211 km s<jats:sup>−1</jats:sup>, with higher values preferentially found on both sides of the system’s major axis. The velocity of the outflow is validated with the blueshift of low-ionization metal absorption lines in the spectra of the central galaxies. We also identify a faint (<jats:italic>M</jats:italic> <jats:sub>1500</jats:sub> ≈ −16.7) companion detected in both Ly<jats:italic>α</jats:italic> and the continuum, whose properties are in agreement with a predicted population of satellite galaxies that contribute to the extended Ly<jats:italic>α</jats:italic> emission. Finally, we briefly discuss the impact of the interaction between the central galaxies on the properties of the halo and the possibility of in situ fluorescent Ly<jats:italic>α</jats:italic> production.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present a joint analysis of the power spectra of the Planck Compton <jats:italic>y</jats:italic> parameter map and the projected galaxy density field using the Wide Field Infrared Survey Explorer (WISE) all-sky survey. We detect the statistical correlation between WISE and Planck data (g<jats:italic>y</jats:italic>) with a significance of 21.8<jats:italic>σ</jats:italic>. We also measure the autocorrelation spectrum for the thermal Sunyaev–Zel’dovich (tSZ) (<jats:italic>yy</jats:italic>) and the galaxy density field maps (gg) with a significance of 150<jats:italic>σ</jats:italic> and 88<jats:italic>σ</jats:italic>, respectively. We then construct a halo model and use the measured correlations <jats:inline-formula> <jats:tex-math> <?CDATA ${C}_{{\ell }}^{\mathrm{gg}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>C</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="italic">ℓ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>gg</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, <jats:inline-formula> <jats:tex-math> <?CDATA ${C}_{{\ell }}^{{yy}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>C</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="italic">ℓ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="italic">yy</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn2.gif" xlink:type="simple" /> </jats:inline-formula>, and <jats:inline-formula> <jats:tex-math> <?CDATA ${C}_{{\ell }}^{{\rm{g}}y}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>C</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="italic">ℓ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">g</mml:mi> <mml:mi>y</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn3.gif" xlink:type="simple" /> </jats:inline-formula> to constrain the tSZ mass bias <jats:inline-formula> <jats:tex-math> <?CDATA $B\equiv {M}_{500}/{M}_{500}^{\mathrm{tSZ}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>B</mml:mi> <mml:mo>≡</mml:mo> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>500</mml:mn> </mml:mrow> </mml:msub> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:msubsup> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>500</mml:mn> </mml:mrow> <mml:mrow> <mml:mi>tSZ</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn4.gif" xlink:type="simple" /> </jats:inline-formula>. We also fit for the galaxy bias, which is included with explicit redshift and multipole dependencies as <jats:inline-formula> <jats:tex-math> <?CDATA ${b}_{{\rm{g}}}{(z,{\ell })={b}_{{\rm{g}}}^{0}(1+z)}^{\alpha }{({\ell }/{{\ell }}_{0})}^{\beta }$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>b</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">g</mml:mi> </mml:mrow> </mml:msub> <mml:msup> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mi>z</mml:mi> <mml:mo>,</mml:mo> <mml:mi mathvariant="italic">ℓ</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mi>b</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">g</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>1</mml:mn> <mml:mo>+</mml:mo> <mml:mi>z</mml:mi> <mml:mo stretchy="false">)</mml:mo> </mml:mrow> <mml:mrow> <mml:mi>α</mml:mi> </mml:mrow> </mml:msup> <mml:msup> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mi mathvariant="italic">ℓ</mml:mi> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:msub> <mml:mrow> <mml:mi mathvariant="italic">ℓ</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> </mml:msub> <mml:mo stretchy="false">)</mml:mo> </mml:mrow> <mml:mrow> <mml:mi>β</mml:mi> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn5.gif" xlink:type="simple" /> </jats:inline-formula>, with <jats:italic>ℓ</jats:italic> <jats:sub>0</jats:sub> = 117. We obtain the constraints to be <jats:italic>B</jats:italic> = 1.50 ± 0.07(stat) ± 0.34(sys), i.e., 1 − <jats:italic>b</jats:italic> <jats:sub>H</jats:sub> = 0.67 ± 0.03(stat) ± 0.16(sys) (68% confidence level) for the hydrostatic mass bias, and <jats:inline-formula> <jats:tex-math> <?CDATA ${b}_{{\rm{g}}}^{0}={1.28}_{-0.04}^{+0.03}(\mathrm{stat})\pm 0.11(\mathrm{sys})$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>b</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">g</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>1.28</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.04</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.03</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo stretchy="false">(</mml:mo> <mml:mi>stat</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo>±</mml:mo> <mml:mn>0.11</mml:mn> <mml:mo stretchy="false">(</mml:mo> <mml:mi>sys</mml:mi> <mml:mo stretchy="false">)</mml:mo> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn6.gif" xlink:type="simple" /> </jats:inline-formula>, with <jats:inline-formula> <jats:tex-math> <?CDATA $\alpha ={0.20}_{-0.07}^{+0.11}(\mathrm{stat})\pm 0.10(\mathrm{sys})$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>α</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>0.20</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.07</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.11</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo stretchy="false">(</mml:mo> <mml:mi>stat</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo>±</mml:mo> <mml:mn>0.10</mml:mn> <mml:mo stretchy="false">(</mml:mo> <mml:mi>sys</mml:mi> <mml:mo stretchy="false">)</mml:mo> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7b8cieqn7.gif" xlink:type="simple" /> </jats:inline-formula> and <jats:italic>β</jats:italic> = 0.45 ±0.01(stat) ± 0.02(sys) for the galaxy bias. Incoming data sets from future CMB and galaxy surveys (e.g., Rubin Observatory) will allow probing the large-scale gas distribution in more detail.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The center of the nearby galaxy NGC 253 hosts a population of more than a dozen super star clusters (SSCs) that are still in the process of forming. The majority of the star formation of the burst is concentrated in these SSCs, and the starburst is powering a multiphase outflow from the galaxy. In this work, we measure the 350 GHz dust continuum emission toward the center of NGC 253 at 47 mas (0.8 pc) resolution using data from the Atacama Large Millimeter/submillimeter Array. We report the detection of 350 GHz (dust) continuum emission in the outflow for the first time, associated with the prominent South-West streamer. In this feature, the dust emission has a width of ≈8 pc, is located at the outer edge of the CO emission, and corresponds to a molecular gas mass of ∼(8–17)×10<jats:sup>6</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>. In the starburst nucleus, we measure the resolved radial profiles, sizes, and molecular gas masses of the SSCs. Compared to previous work at the somewhat lower spatial resolution, the SSCs here break apart into smaller substructures with radii 0.4–0.7 pc. In projection, the SSCs, dust, and dense molecular gas appear to be arranged as a thin, almost linear, structure roughly 155 pc in length. The morphology and kinematics of this structure can be well explained as gas following <jats:italic>x</jats:italic> <jats:sub>2</jats:sub> orbits at the center of a barred potential. We constrain the morpho-kinematic arrangement of the SSCs themselves, finding that an elliptical, angular-momentum-conserving ring is a good description of both the morphology and kinematics of the SSCs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present the Waves in Nearby Disk galaxies Survey (WiNDS) consisting of 40 nearby low-inclination disk galaxies observed through H<jats:sub> <jats:italic>α</jats:italic> </jats:sub> high-resolution Fabry–Perot interferometry. WiNDS consists of 12 new galaxy observations and 28 data archived observations obtained from different galaxy surveys. We derive two-dimensional line-of-sight velocity fields that are analyzed to identify the possible presence of vertical velocity flows in the galactic disks of these low-inclination late-type galaxies using velocity residual maps, derived from the subtraction of an axisymmetric rotation model from a rotational velocity map. Large and globally coherent flows in the line-of-sight velocity of nearly face-on galaxies can be associated with large vertical displacement of the disk with respect to its midplane. Our goal is to characterize how frequent vertical perturbations, such as those observed in the Milky Way, arise in the local universe. Our currently available data have allowed us to identify 20% of WiNDS galaxies with strong velocity perturbations that are consistent with vertically perturbed galactic disks.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We seek signatures of the current experimental <jats:sup>12</jats:sup>C <jats:inline-formula> <jats:tex-math> <?CDATA ${\left(\alpha ,\gamma \right)}^{16}{\rm{O}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mfenced close=")" open="("> <mml:mrow> <mml:mi>α</mml:mi> <mml:mo>,</mml:mo> <mml:mi>γ</mml:mi> </mml:mrow> </mml:mfenced> </mml:mrow> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ec3ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> reaction rate probability distribution function in the pulsation periods of carbon–oxygen white dwarf (WD) models. We find that adiabatic g-modes trapped by the interior carbon-rich layer offer potentially useful signatures of this reaction rate probability distribution function. Probing the carbon-rich region is relevant because it forms during the evolution of low-mass stars under radiative helium-burning conditions, mitigating the impact of convective mixing processes. We make direct quantitative connections between the pulsation periods of the identified trapped g-modes in variable WD models and the current experimental <jats:sup>12</jats:sup>C <jats:inline-formula> <jats:tex-math> <?CDATA ${\left(\alpha ,\gamma \right)}^{16}{\rm{O}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mfenced close=")" open="("> <mml:mrow> <mml:mi>α</mml:mi> <mml:mo>,</mml:mo> <mml:mi>γ</mml:mi> </mml:mrow> </mml:mfenced> </mml:mrow> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ec3ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> reaction rate probability distribution function. We find an average spread in relative period shifts of Δ<jats:italic>P</jats:italic>/<jats:italic>P</jats:italic> ≃ ±2% for the identified trapped g-modes over the ±3<jats:italic>σ</jats:italic> uncertainty in the <jats:sup>12</jats:sup>C <jats:inline-formula> <jats:tex-math> <?CDATA ${\left(\alpha ,\gamma \right)}^{16}{\rm{O}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mfenced close=")" open="("> <mml:mrow> <mml:mi>α</mml:mi> <mml:mo>,</mml:mo> <mml:mi>γ</mml:mi> </mml:mrow> </mml:mfenced> </mml:mrow> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ec3ieqn3.gif" xlink:type="simple" /> </jats:inline-formula> reaction rate probability distribution function—across the effective temperature range of observed DAV and DBV WDs and for different WD masses, helium shell masses, and hydrogen shell masses. The g-mode pulsation periods of observed WDs are typically given to six to seven significant figures of precision. This suggests that an astrophysical constraint on the <jats:sup>12</jats:sup>C <jats:inline-formula> <jats:tex-math> <?CDATA ${\left(\alpha ,\gamma \right)}^{16}{\rm{O}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mfenced close=")" open="("> <mml:mrow> <mml:mi>α</mml:mi> <mml:mo>,</mml:mo> <mml:mi>γ</mml:mi> </mml:mrow> </mml:mfenced> </mml:mrow> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac7ec3ieqn4.gif" xlink:type="simple" /> </jats:inline-formula> reaction rate could, in principle, be extractable from the period spectrum of observed variable WDs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Astrophysical jets are launched from strongly magnetized systems that host an accretion disk surrounding a central object. The origin of the magnetic field, which is a key component of the launching process, is still an open question. Here we address the question of how the magnetic field required for jet launching is generated and maintained by a dynamo process. By carrying out nonideal MHD simulations (PLUTO code), we investigate how the feedback of the generated magnetic field on the mean-field dynamo affects the disk and jet properties. We find that a stronger quenching of the dynamo leads to a saturation of the magnetic field at a lower disk magnetization. Nevertheless, we find that, while applying different dynamo feedback models, the overall jet properties remain unaffected. We then investigate a feedback model that encompasses a quenching of the magnetic diffusivity. Our modeling considers a more consistent approach for mean-field dynamo modeling simulations, as the magnetic quenching of turbulence should be considered for both a turbulent dynamo and turbulent magnetic diffusivity. We find that, after the magnetic field is saturated, the Blandford–Payne mechanism can work efficiently, leading to more collimated jets, which move, however, with slower speed. We find strong intermittent periods of flaring and knot ejection for low Coriolis numbers. In particular, flux ropes are built up and advected toward the inner disk thereby cutting off the inner disk wind, leading to magnetic field reversals, reconnection and, the emergence of intermittent flares.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Due to the latest advances in technology, telescopes with significant sky coverage will produce millions of astronomical alerts per night that must be classified both rapidly and automatically. Currently, classification consists of supervised machine-learning algorithms whose performance is limited by the number of existing annotations of astronomical objects and their highly imbalanced class distributions. In this work, we propose a data augmentation methodology based on generative adversarial networks (GANs) to generate a variety of synthetic light curves from variable stars. Our novel contributions, consisting of a resampling technique and an evaluation metric, can assess the quality of generative models in unbalanced data sets and identify GAN-overfitting cases that the Fréchet inception distance does not reveal. We applied our proposed model to two data sets taken from the Catalina and Zwicky Transient Facility surveys. The classification accuracy of variable stars is improved significantly when training with synthetic data and testing with real data with respect to the case of using only real data.</jats:p>