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<jats:title>Abstract</jats:title> <jats:p>We use combined South Pole Telescope (SPT)+Planck temperature maps to analyze the circumgalactic medium (CGM) encompassing 138,235 massive, quiescent 0.5 ≤ <jats:italic>z</jats:italic> ≤ 1.5 galaxies selected from data from the Dark Energy Survey (DES) and Wide-Field Infrared Survey Explorer (WISE). Images centered on these galaxies were cut from the 1.85 arcmin resolution maps with frequency bands at 95, 150, and 220 GHz. The images were stacked, filtered, and fit with a graybody dust model to isolate the thermal Sunyaev–Zel’dovich (tSZ) signal, which is proportional to the total energy contained in the CGM of the galaxies. We separated these <jats:italic>M</jats:italic> <jats:sub>⋆</jats:sub> = 10<jats:sup>10.9</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>–10<jats:sup>12</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> galaxies into 0.1 dex stellar mass bins, detecting tSZ per bin up to 5.6<jats:italic>σ</jats:italic> and a total signal-to-noise ratio of 10.1<jats:italic>σ</jats:italic>. We also detect dust with an overall signal-to-noise ratio of 9.8<jats:italic>σ</jats:italic>, which overwhelms the tSZ at 150 GHz more than in other lower-redshift studies. We corrected for the 0.16 dex uncertainty in the stellar mass measurements by parameter fitting for an unconvolved power-law energy-mass relation, <jats:inline-formula> <jats:tex-math> <?CDATA ${E}_{\mathrm{therm}}={E}_{\mathrm{therm},\mathrm{peak}}{\left({M}_{\star }/{M}_{\star ,\mathrm{peak}}\right)}^{\alpha }$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>E</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>therm</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msub> <mml:mrow> <mml:mi>E</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>therm</mml:mi> <mml:mo>,</mml:mo> <mml:mi>peak</mml:mi> </mml:mrow> </mml:msub> <mml:msup> <mml:mrow> <mml:mfenced close=")" open="("> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> </mml:mrow> </mml:msub> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> <mml:mo>,</mml:mo> <mml:mi>peak</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> </mml:mfenced> </mml:mrow> <mml:mrow> <mml:mi>α</mml:mi> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf2b4ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, with the peak stellar mass distribution of our selected galaxies defined as <jats:italic>M</jats:italic> <jats:sub>⋆,peak</jats:sub> = 2.3 × 10<jats:sup>11</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>. This yields an <jats:inline-formula> <jats:tex-math> <?CDATA ${E}_{\mathrm{therm},\mathrm{peak}}={5.98}_{-1.00}^{+1.02}\,\times {10}^{60}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>E</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>therm</mml:mi> <mml:mo>,</mml:mo> <mml:mi>peak</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>5.98</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1.00</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>1.02</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace width="0.25em" /> <mml:mo>×</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mn>60</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf2b4ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> erg and <jats:inline-formula> <jats:tex-math> <?CDATA $\alpha ={3.77}_{-0.74}^{+0.60}$?> </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>3.77</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.74</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.60</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf2b4ieqn3.gif" xlink:type="simple" /> </jats:inline-formula>. These are consistent with <jats:italic>z</jats:italic> ≈ 0 observations and within the limits of moderate models of active galactic nucleus feedback. We also computed the radial profile of our full sample, which is similar to that recently measured at lower-redshift by Schaan et al.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We investigate 16 solar energetic electron (SEE) events measured by WIND/3DP with a double-power-law spectrum and the associated western hard X-ray (HXR) flares measured by RHESSI with good count statistics, from 2002 February to 2016 December. In all the 16 cases, the presence of an SEE power-law spectrum extending down to ≤5 keV at 1 au implies that the SEE source would be high in the corona, at a heliocentric distance of ≥1.3 solar radii, while the footpoint or footpoint-like emissions shown in HXR images suggest that the observed HXRs are likely produced mainly by HXR-producing electrons via thick-target bremsstrahlung processes very low in the corona. We find that for all the 16 cases, the estimated power-law spectral index of HXR-producing electrons is no less than the observed high-energy spectral index of SEEs, and it shows a positive correlation with the high-energy spectral index of SEEs. In addition, the estimated number of SEEs is only ∼10<jats:sup>−4</jats:sup>–10<jats:sup>−2</jats:sup> of the estimated number of HXR-producing electrons at energies above 30 keV, but with a positive correlation between the two numbers. These results suggest that in these cases, SEEs are likely formed by upward-traveling electrons from an acceleration source high in the corona, while their downward-traveling counterparts may undergo a secondary acceleration before producing HXRs via thick-target bremsstrahlung processes. In addition, the associated <jats:sup>3</jats:sup>He/<jats:sup>4</jats:sup>He ratio is positively correlated with the observed high-energy spectral index of SEEs, indicating a possible relation of the <jats:sup>3</jats:sup>He ion acceleration with high-energy SEEs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Presolar silicon carbide (SiC) grains in meteoritic samples can help constrain circumstellar condensation processes and conditions in C-rich stars and core-collapse supernovae (CCSNe). This study presents our findings on eight presolar SiC grains from asymptotic giant branch (AGB) stars (four mainstream and one Y grain) and CCSNe (three X grains), chosen on the basis of <jats:italic>μ</jats:italic>-Raman spectral features that were indicative of their having unusual non-3C polytypes and/or high degrees of crystal disorder. Analytical transmission electron microscopy (TEM), which provides elemental compositional and structural information, shows evidence for complex histories for the grains. Our TEM results confirm the presence of non-3C,2H crystal domains. Minor-element heterogeneities and/or subgrains were observed in all grains analyzed for their compositions. The C/O ratios inferred for the parent stars varied from 0.98 to ≥1.03. Our data show that SiC condensation can occur under a wide range of conditions, in which environmental factors other than temperature (e.g., pressure, gas composition, heterogeneous nucleation on precondensed phases) play a significant role. Based on previous <jats:italic>μ</jats:italic>-Raman studies, ∼10% of SiC grains may have infrared (IR) spectral features that are influenced by crystal defects, porosity, and/or subgrains. Future sub-diffraction-limited IR measurements of complex SiC grains might shed further light on the relative contributions of each of these features to the shape and position of the characteristic IR 11 <jats:italic>μ</jats:italic>m SiC feature and thus improve the interpretation of IR spectra of AGB stars like those that produced the presolar SiC grains.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We conduct three-dimensional hydrodynamical numerical simulations of planetary nebula (PN) shaping and show that jets that precede the ejection of the main PN shell can form the morphological feature of ears. Ears are two opposite protrusions from the main nebula that are smaller than the main nebula and with a cross section that decreases monotonically from the base of an ear at the shell to its far end. Only a very small fraction of PNe have ears. The short-lived jets, about a year in the present simulations, interact with the regular asymptotic giant branch wind to form the ears, while the later blown dense wind forms the main PN dense shell. Namely, the jets are older than the main PN shell. We also find that for the jets to inflate ears they cannot be too energetic, cannot be too wide, and cannot be too slow. A flow structure where short-lived jets precede the main phase of nebula ejection by a few years or less can result from a system that enters a common envelope evolution. The low mass companion accretes mass through an accretion disk and launches jets just before it enters the envelope of the giant progenitor star of the PN. Shortly after that the companion enters the envelope and spirals-in to eject the envelope that forms the main PN shell.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Disk vortices have been heralded as promising routes for planet formation due to their ability to trap significant amounts of pebbles. While the gas motions and trapping properties of two-dimensional vortices have been studied in enough detail in the literature, pebble trapping in three dimensions has received less attention, due to the higher computational demand. Here we use the <jats:sc>Pencil Code</jats:sc> to study 3D vortices generated by convective overstability and the trapping of solids within them. The gas is unstratified whereas the pebbles settle to the midplane due to vertical gravity. We find that for pebbles of normalized friction times of <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{St}=0.05$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>St</mml:mi> <mml:mo>=</mml:mo> <mml:mn>0.05</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf739ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> and <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{St}=1$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>St</mml:mi> <mml:mo>=</mml:mo> <mml:mn>1</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf739ieqn2.gif" xlink:type="simple" /> </jats:inline-formula>, and dust-to-gas ratio <jats:inline-formula> <jats:tex-math> <?CDATA $\varepsilon =0.01$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> <mml:mo>=</mml:mo> <mml:mn>0.01</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf739ieqn3.gif" xlink:type="simple" /> </jats:inline-formula>, the vortex column in the midplane is strongly perturbed. Yet when the initial dust-to-gas ratio is decreased the vortices remain stable and function as efficient pebble traps. Streaming instability is triggered even for the lowest dust-to-gas ratio (<jats:inline-formula> <jats:tex-math> <?CDATA ${\varepsilon }_{0}={10}^{-4}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>ε</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>4</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf739ieqn4.gif" xlink:type="simple" /> </jats:inline-formula>) and smallest pebble sizes (<jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{St}=0.05$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>St</mml:mi> <mml:mo>=</mml:mo> <mml:mn>0.05</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabf739ieqn5.gif" xlink:type="simple" /> </jats:inline-formula>) we assumed, showing a path for planetesimal formation in vortex cores from even extremely subsolar metallicity. To estimate if the reached overdensities can be held together solely by their own gravity we estimate the Roche density at different radii. Depending on disk model and radial location of the pebble clump we do reach concentrations higher than the Roche density. We infer that if self-gravity was included for the pebbles then gravitational collapse would likely occur.</jats:p>