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<jats:title>Abstract</jats:title> <jats:p>We have investigated electromagnetic (EM) wave pulses in a jet from a neutrino-driven accretion flow (NDAF) around a black hole (BH). NDAFs are massive accretion disks whose accretion rates are <jats:inline-formula> <jats:tex-math> <?CDATA $\dot{M}\,\approx $?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>̇</mml:mo> </mml:mrow> </mml:mover> <mml:mspace width="0.2em" /> <mml:mo>≈</mml:mo> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjac56e3ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> 0.01–10 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> s<jats:sup>−1</jats:sup> for stellar-mass BHs. Such an extreme accretion may produce a collimated relativistic outflow like a magnetically driven jet in active galactic nuclei and microquasars. When we consider strong toroidal magnetic field stranded in the inner region of an NDAF disk and magnetic impulses on the jet, we find that they lead to the emanation of high-energy emissions for gamma-ray bursts, as well as high-energy cosmic rays. When Alfvénic wave pulses are generated by episodic immense accretions, they propagate along the large-scale structured magnetic field in the jet. Once the Alfvénic wave pulses reach nearly the speed of light in the underdense condition, they turn into EM wave pulses, which produce plasma wakes behind them. These wakefields exert a collective accelerating force synchronous to the motion of particles. As a result, the wakefield acceleration premises various observational signatures, such as pulsating bursts of high-energy gamma rays from accelerated electrons, pulses of neutrinos from accelerated protons, and protons with maximum energies beyond 10<jats:sup>20</jats:sup> eV.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this fifth paper of the series, we use the parameterized, spherically symmetric explosion method PUSH to investigate the impact of eight different nuclear equations of state (EOS). We present and discuss the explosion properties and the detailed nucleosynthesis yields, and predict the remnant (neutron star or black hole) for all our simulations. For this, we perform two sets of simulations. First, a complete study of nonrotating stars from 11 to 40 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> at three different metallicities using the SFHo EOS; and, second, a suite of simulations for four progenitors (16 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> at three metallicities and 25 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> at solar metallicity) for eight different nuclear EOS. We compare our predicted explosion energies and yields to observed supernovae and to the metal-poor star HD 84937. We find EOS-dependent differences in the explosion properties and the nucleosynthesis yields. However, when comparing to observations, these differences are not large enough to rule out any EOS considered in this work.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>A kilonova (KN) signal is generally expected after a black hole–neutron star merger. The strength of the signal is related to the equation of state of neutron star matter, and it increases with the stiffness of the latter. The recent results obtained by NICER from the analyses of PSR J0740+6620 suggest a rather stiff equation of state, and the expected KN signal is therefore strong, at least if the mass of the black hole does not exceed ∼10 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, the adimensional spin parameter is not too small, and the orbit is prograde. We compare the predictions obtained by considering equations of state of neutron star matter satisfying the most recent observations and assuming that only one family of compact stars exists with the results predicted in the two-families scenario. In the latter a soft hadronic equation of state produces very compact stellar objects, while a rather stiff quark matter equation of state produces massive strange quark stars, satisfying NICER results. The expected KN signal in the two-families scenario is very weak: in particular, the hadronic star–black hole merger produces a much weaker signal than in the one-family scenario because the hadronic equation of state is very soft. Moreover, according to the only existing simulation, the strange quark star–black hole merger does not produce a KN signal because the amount of mass ejected is negligible. These predictions will be easily tested with the new generation of detectors if black holes with an adimensional spin parameter <jats:italic>χ</jats:italic> <jats:sub>BH</jats:sub> ≳ 0.2 or a mass <jats:italic>M</jats:italic> <jats:sub>BH</jats:sub> ≲ 4<jats:italic> M</jats:italic> <jats:sub>⊙</jats:sub> can be present in the merger.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The encounter of the Parker Solar Probe (PSP) with Venus during the Venus Gravity Assist 3 on 2020 July 11 provided a unique opportunity to gather in situ solar wind data in the Venusian environment while also being able to observe Venus from ground-based facilities on Earth. The Wang–Sheeley–Arge (WSA) model was used to make accurate predictions of solar wind velocity and interplanetary magnetic field polarity at Earth and STEREO-A, as compared to in situ data at each spacecraft. The same model was then used to predict solar wind conditions at Venus. The predictions were in good agreement with in situ PSP data, as they match the overall magnitude and structure of the solar wind velocity and magnetic polarity at multiple spacecraft. This demonstrates that WSA can be used to make reliable predictions at locations in the heliosphere when in situ data is not available. Venusian aurorae were detected via emission in the oxygen green line 5577 Å OI(<jats:sup>1</jats:sup> <jats:italic>S</jats:italic> − <jats:sup>1</jats:sup> <jats:italic>D</jats:italic>) at the same time that PSP captured a heliospheric current sheet crossing, and shortly thereafter, detected an increase in proton count rate. This is the first observation of oxygen green line aurora on Venus that is not the direct result of a coronal mass ejection, a solar flare, or corotating interaction regions.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present a novel physically motivated, parametrized temperature model for phase-curve retrieval, able to self-consistently assess the variation in thermal structure in multidimensions. To develop this approach, we drew motivation from both full three-dimensional general circulation models and analytic formulations, accounting for the dominant dynamical feature of tidally locked planets, the planetary jet. Our formulation shows notable flexibility. It can generate planetary jets of various characteristics and redistribution efficiencies seen in the literature, including both standard eastward and unusual westward offset hotspots, as well as more exotic configurations for potential future observations. In our modeling scheme we utilize a tractable set of parameters efficient enough to enable future Bayesian analysis and, in addition to the resolved temperature structure, we return physical insights not yet derived from retrievals: the amplitude and the phase offset, and the location and the extent of the equatorial jet.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present an extensive exploration of the impact of 29 physical parameters in the oxygen abundance for a sample of 299 star-forming galaxies extracted from the extended Calar Alto Legacy Integral Field Area Survey sample. We corroborate that the stellar mass is the physical parameter that better traces the observed oxygen abundance (i.e., the mass–metallicity relation; MZR), while other physical parameters could play a potential role in shaping this abundance, but with a lower significant impact. We find that the functional form that best describes the MZR is a third-order polynomial function. From the residuals between this best functional form and the MZR, we find that once considered the impact of the mass in the oxygen abundance, the other physical parameters do not play a significant secondary role in shaping the oxygen abundance in these galaxies (including the gas fraction or the star formation rate). Our analysis suggests that the origin of the MZR is related to the chemical enrichment evolution of the interstellar medium due, most likely, to the buildup of stellar mass in these star-forming galaxies.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We look for empirical evidence of a nonminimal coupling (NMC) between dark matter (DM) and gravity in the dynamics of local spiral galaxies. In particular, we consider a theoretically motivated NMC that may arise dynamically from the collective behavior of the coarse-grained DM field (e.g., via Bose–Einstein condensation) with averaging/coherence length <jats:italic>L</jats:italic>. In the Newtonian limit, this NMC amounts to modify the Poisson equation by a term <jats:italic>L</jats:italic> <jats:sup>2</jats:sup>∇<jats:sup>2</jats:sup> <jats:italic>ρ</jats:italic> proportional to the Laplacian of the DM density itself. We show that such a term, when acting as a perturbation over the standard Navarro–Frenk–White profile of cold DM particles, can substantially alter the dynamical properties of galaxies, in terms of their total radial acceleration within the disk and rotation velocity. Specifically, we find that this NMC model can properly fit the stacked rotation curves (RCs) of local spiral galaxies with different velocities at the optical radius, including dwarfs and low-surface-brightness systems, at a level of precision comparable to, and in some instances even better than, the phenomenological Burkert profile. Finally, we show that by extrapolating down to smaller masses the scaling of <jats:italic>L</jats:italic> versus halo mass found from the above RC analysis, the NMC model can adequately reproduce the radial acceleration relation in shape and normalization down to the dwarf spheroidal galaxy range, a task which constitutes a serious challenge for alternative DM models even inclusive of baryonic effects.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The Event Horizon Telescope (EHT) recently released the first linearly polarized images of the accretion flow around the supermassive black hole Messier 87*, hereafter M87*. The spiraling polarization pattern found in the EHT images favored magnetically arrested disks as the explanation for the EHT image. With next-generation improvements to very long baseline interferometry on the horizon, understanding similar polarized features in the highly lensed structure known as the “photon ring,” where photons make multiple half orbits about the black hole before reaching the observer, will be critical to the analysis of future images. Recent work has indicated that this image region may be depolarized relative to more direct emission. We expand this observation by decomposing photon half orbits in the EHT library of simulated images of the M 87* accretion system and find that images of magnetically arrested disk simulations show a relative depolarization of the photon ring attributable to destructive interference of oppositely spiraling electric field vectors; this antisymmetry, which arises purely from strong gravitational lensing, can produce up to ∼50% depolarization in the photon ring region with respect to the direct image. In systems that are not magnetically arrested and with the exception of systems with high spin and ions and electrons of equal temperature, we find that highly lensed indirect subimages are almost completely depolarized, causing a modest depolarization of the photon ring region in the complete image. We predict that next-generation EHT observations of M 87* polarization should jointly constrain the black hole spin and the underlying emission and magnetic field geometry.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Extreme emission-line galaxies, such as blue compact dwarfs (BCDs), Green Peas (GPs), and blueberries in the local universe are potential candidates for understanding the nature of galaxies that reionized the early universe. Being low-mass, metal-poor starburst systems, they are understood to be local analogs of the high-redshift Lyman continuum and Ly<jats:italic>α</jats:italic> emitters (LAEs). Even with their proximity to us, we know little about their spatially resolved properties; while most blueberries and GPs are indeed compact, they remain unresolved. Here, we report the detection of a disk-like lower-surface-brightness (LSB) stellar host with a very old population around a blueberry LAE system using broad <jats:italic>i</jats:italic>-band imaging and integral field spectroscopic data from the SDSS and SDSS-IV MaNGA surveys, respectively. The LSB stellar host is structurally similar to that observed around local starburst BCDs. Furthermore, the kinematics of the studied blueberry source bears signs of misalignment between the gas and stellar components. Our findings establish an intriguing thread connecting the blueberry and an LSB disk with an old stellar population and suggest that blueberries and their high-redshift counterparts such as GPs do not represent peculiar cases of dwarf galaxy evolution. In fact, with respect to the structural properties of their host galaxies, they are compatible with a common evolutionary track of the main population of local BCDs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this paper, we use high-quality rest-UV spectra of three radio galaxies at <jats:italic>z</jats:italic> ∼ 3 observed with the FORS2 camera on the Very Large Telescope to measure the flux of several emission lines, including relatively faint ones, such as N <jats:sc>iv</jats:sc>]<jats:italic>λ</jats:italic>1486, O <jats:sc>iii</jats:sc>]<jats:italic>λ</jats:italic>1663, and [Ne <jats:sc>iv</jats:sc>]<jats:italic>λ</jats:italic>2424. Additionally, we collect fluxes of faint rest-UV emission lines in 12 <jats:italic>z</jats:italic> ∼ 3 radio galaxies from the literature. Previously, physical and chemical properties of narrow-line regions (NLRs) in high-<jats:italic>z</jats:italic> active galactic nuclei (AGNs) have been investigated mostly by using only strong rest-UV emission lines (e.g., N <jats:sc>v</jats:sc> <jats:italic>λ</jats:italic>1240, C <jats:sc>iv</jats:sc> <jats:italic>λ</jats:italic>1549, He <jats:sc>ii</jats:sc> <jats:italic>λ</jats:italic>1640, and C <jats:sc>iii</jats:sc>]<jats:italic>λ</jats:italic>1909). Such strong-line diagnostics are based on various assumptions due to the limitation in the number of available emission-line constraints. In this work, both physical and chemical properties of NLR clouds in each object are estimated by fitting detailed photoionization models to the measured emission-line fluxes. We confirm that the metallicity of NLRs in AGNs at <jats:italic>z</jats:italic> ∼ 3 is solar or supersolar, without assumptions about the gas density and ionization parameter thanks to the constraints from the faint emission lines. This result suggests that high-<jats:italic>z</jats:italic> radio galaxies are already chemically mature at <jats:italic>z</jats:italic> ∼ 3.</jats:p>