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<jats:title>Abstract</jats:title> <jats:p>Using numerical simulations, we study the effects of magnetic resistivity and thermal conductivity in the dynamics and properties of solar jets with characteristics of Type II spicules and cool coronal jets. The dynamic evolution of the jets is governed by the resistive MHD equations with thermal conduction along the magnetic field lines on a 2.5D slice. The magnetic field configuration consists of two symmetric neighboring loops with opposite polarity, used to support reconnection and followed by the plasma jet formation. In total, 10 simulations were carried out with different values of resistivity and thermal conductivity that produce jets with different morphological and thermal properties we quantify. We find that an increase in magnetic resistivity does not produce significant effects on the morphology, velocity, and temperature of the jets. However, thermal conductivity affects both temperature and morphology of the jets. In particular, thermal conductivity causes jets to reach greater heights and increases the temperature of the jet-apex. Also, heat flux maps indicate the jet-apex and corona interchange energy more efficiently than the body of the jet. These results could potentially open a new avenue for plasma diagnostics in the Sun’s atmosphere.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present multiwavelength photometric and spectroscopic observations of SN 2019ein, a high-velocity Type Ia supernova (SN Ia) discovered in the nearby galaxy NGC 5353 with a two-day nondetection limit. SN 2019ein exhibited some of the highest measured expansion velocities of any SN Ia, with a Si <jats:sc>ii</jats:sc> absorption minimum blueshifted by 24,000 km s<jats:sup>−1</jats:sup> at 14 days before peak brightness. More unusually, we observed the emission components of the P Cygni profiles to be blueshifted upward of 10,000 km s<jats:sup>−1</jats:sup> before <jats:italic>B</jats:italic>-band maximum light. This blueshift, among the highest in a sample of 28 other SNe Ia, is greatest at our earliest spectroscopic epoch and subsequently decreases toward maximum light. We discuss possible progenitor systems and explosion mechanisms that could explain these extreme absorption and emission velocities. Radio observations beginning 14 days before <jats:italic>B</jats:italic>-band maximum light yield nondetections at the position of SN 2019ein, which rules out symbiotic progenitor systems, most models of fast optically thick accretion winds, and optically thin shells of mass <jats:inline-formula> <jats:tex-math> <?CDATA $\lesssim {10}^{-6}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjab8e3fieqn1.gif" xlink:type="simple" /> </jats:inline-formula> <jats:inline-formula> <jats:tex-math> <?CDATA ${M}_{\odot }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjab8e3fieqn2.gif" xlink:type="simple" /> </jats:inline-formula> at radii <jats:inline-formula> <jats:tex-math> <?CDATA $\lt 100\,\mathrm{au}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjab8e3fieqn3.gif" xlink:type="simple" /> </jats:inline-formula>. Comparing our spectra to models and observations of other high-velocity SNe Ia, we find that SN 2019ein is well fit by a delayed-detonation explosion. We propose that the high emission velocities may be the result of abundance enhancements due to ejecta mixing in an asymmetric explosion, or optical depth effects in the photosphere of the ejecta at early times. These findings may provide evidence for common explosion mechanisms and ejecta geometries among high-velocity SNe Ia.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>To understand the formation and quenching processes of local massive red spiral galaxies with <jats:italic>M</jats:italic> <jats:sub>*</jats:sub> &gt; 10<jats:sup>10.5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, we perform a statistical analysis of their spectroscopic and structural properties and compare them with elliptical and blue spiral galaxies of similar mass. The sample was selected from the stellar mass catalog of galaxies in SDSS DR7, according to their locations on the <jats:italic>u</jats:italic> − <jats:italic>r</jats:italic> color−stellar mass diagram. We find that red spirals harbor compact cores with high stellar mass surface densities measured by Σ<jats:sub>1</jats:sub> and are bulge dominated. Particularly, the red spirals, especially their bulges, follow the Σ<jats:sub>1</jats:sub>–<jats:italic>M</jats:italic> <jats:sub>*</jats:sub> ridgeline for quenched galaxies. Furthermore, the red spirals show similarly large central <jats:italic>D</jats:italic> <jats:sub> <jats:italic>n</jats:italic> </jats:sub>(4000), high [Mg/Fe], and dark matter halo mass to ellipticals. These results suggest that the bulges of red spirals formed within a short timescale before redshift ∼1–2 and were quenched via a fast mode, similar to ellipticals. Careful examinations of the optical morphologies reveal that ∼70% of red spirals show strong bars, rings/shells, and even merging features, which suggests that interactions or mergers might have played an important role in the formation of red spirals. In contrast, most of the massive blue spirals have completely different spectral and structural properties from red spirals. However, the blue spirals with high Σ<jats:sub>1</jats:sub> (<jats:inline-formula> <jats:tex-math> <?CDATA ${{\rm{\Sigma }}}_{1}\gt {10}^{9.5}\,{M}_{\odot }\,{\mathrm{kpc}}^{-2}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjab9b75ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>) show similar structural and morphological properties, as well as similar halo mass and H <jats:sc>i</jats:sc> mass to red spirals. We discuss rejuvenation from red to blue as a possible explanation for these high-Σ<jats:sub>1</jats:sub> blue spirals.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>It is unclear how galaxies and their central supermassive black holes coevolve across cosmic time, especially for the nonlocal universe (<jats:italic>z</jats:italic> ≳ 0.5). The High-<jats:italic>z</jats:italic> Universe probed via Lensing by QSOs project proposes to utilize quasi-stellar object (QSO) host galaxies acting as gravitational lenses (QSO lenses) to investigate this topic. This paper focuses on the feasibility of this project, that is, whether sufficiently large numbers of QSO lenses are expected to be found in various concurrent and future imaging surveys. We find that ∼440 QSO lenses will reside in the Hyper Suprime-Cam Wide survey (HSC/Wide), which is expected to be the most prolific concurrent survey, with this number being boosted by one to two orders of magnitude (to ∼10,000) with upcoming surveys such as that conducted with the Large Synoptic Survey Telescope (LSST). We discuss several methods of how to study the redshift evolution of the <jats:inline-formula> <jats:tex-math> <?CDATA ${M}_{\mathrm{BH}}\mbox{--}{\sigma }_{* }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjab9b23ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> relation, which is a standout illustration of the coevolution. In addition, we demonstrate how the intimacy of lensed images to the bright deflector QSO for most systems will affect the <jats:italic>detectability</jats:italic> of QSO lenses. We estimate that only ∼82 and 900 will be detectable for HSC/Wide and LSST, respectively; the decrease is significant yet still yields an acceptable sample for the main objective. This decrease will be less of a problem for space-based imaging surveys, for their small point-spread function FWHMs will allow detections of lensed images lying relatively close to the deflector QSO, and thus unveil the less massive yet more numerous QSO hosts.</jats:p>