Sazuna/UAT_keywords huggingface dataset:
Catastrophic Cooling in Superwinds: Line Emission and Non-equilibrium Ionization. Outflows are a pervasive feature of mechanical feedback from super star clusters (SSCs) in starburst galaxies, playing a fundamental role in galaxy evolution. Observations are now starting to confirm that outflows can undergo catastrophic cooling, suppressing adiabatic superwinds. Here we present a suite of one-dimensional, hydrodynamic simulations that study the ionization structure of these outflows and the resulting line emission generated by the cooling gas. We use the non-equilibrium atomic chemistry package within MAIHEM, our modified version of FLASH, which evolves the ionization state of the gas and computes the total cooling rate on an ion-by-ion basis. We find that catastrophically cooling models produce strong nebular line emission compared to adiabatic outflows. We also show that such models exhibit non-equilibrium conditions, thereby generating more highly ionized states than equivalent equilibrium models. When including photoionization from the parent SSC, catastrophically cooling models show strong C IV λ1549 and O VI λ1037 emission. For density-bounded photoionization, He II λ1640, λ4686, C III] λ1908, Si IV λ1206, and Si III λ1400 are also strongly enhanced. These lines are seen in extreme starbursts where catastrophic cooling is likely to occur, suggesting that they may serve as diagnostics of such conditions. The higher ionization generated by these flows may help to explain line emission that cannot be attributed to SSC photoionization alone.

Keywords: Starburst galaxies, Stellar-interstellar interactions, Young massive clusters, Emission line galaxies, Interstellar plasma
Effects of Strong Photospheric Dissipation on the Spectra and Structure of Accretion Disks with Nonzero Inner Torque. We present numerical calculations of spectra and structure of accretion disk models appropriate for near-Eddington luminosity black hole X-ray binaries. Our work incorporates nonzero torque at the ISCO as well as several dissipation profiles based on first-principles three-dimensional disk interior simulations. We found that significant dissipation near the photosphere can produce steep power-law-like spectra for models with moderate viewing angles spanning a range of black hole spins while including inner torque pushes the spectral peak to higher energies. Consistent with previous studies, we also conclude that disks with stresses at the inner edge remain viable models for high-frequency quasi-periodic oscillations, especially given that increasing dissipation near the photospheres actually resulted in QPO power spectra with higher quality factors compared to those found in recent work.

Keywords: Stellar accretion disks, Black hole physics, X-ray binary stars, High altitude balloons
Testing Cosmic Opacity with the Combination of Strongly Lensed and Unlensed Supernova Ia. In this paper, we present a scheme to investigate the opacity of the universe in a cosmological-model-independent way, with the combination of current and future measurements of an SN Ia sample and galactic-scale strong gravitational lensing systems with SNe Ia acting as background sources. The observational data include the current newly compiled SNe Ia data (Pantheon sample) and a simulated sample of SNe Ia observed by the forthcoming Large Synoptic Survey Telescope (LSST), which are taken for luminosity distances (D L) possibly affected by the cosmic opacity, as well as strongly lensed SNe Ia observed by the LSST, which are responsible for providing the observed time-delay distance unaffected by the cosmic opacity. Focusing on only one specific type of standard cosmological probe, this provides an original method to measure cosmic opacity at high precision. Working on the simulated sample of strongly lensed SNe Ia observed by the LSST in the 10 yr z-band search, our results show that, with the combination of the current newly compiled SNe Ia data (Pantheon sample), there is no significant deviation from the transparency of the universe at the current observational data level. Moreover, strongly lensed SNe Ia in a 10 yr LSST z-band search would produce more robust constraints on the validity of cosmic transparency, with a larger sample of unlensed SNe Ia detected in the future LSST survey. We have also discussed the ways in which our methodology could be improved, with the combination of current and future available data in the gravitational wave and electromagnetic domain.

Keywords: Strong gravitational lensing, Standard candles, Type Ia supernovae, Cosmological parameters
The Generalized Hardness-Intensity Diagram for Black Hole and Neutron Star X-Ray Binaries. Over the past half-century, X-ray and radio observations of accreting neutron stars and stellar-mass black holes have yielded a rich observational picture, with common features including state transitions and jet formation, but also sharp differences. While black hole X-ray binaries overwhelmingly suppress jets in so-called soft states, accreting neutron stars are less restrictive, with a soft state wind observed in some sources to coexist with a jet. We propose an explanation for these differences that leads to a generalization of a foundational element, the hardness-intensity diagram of Fender et al. The inverse relation between jets and winds fits into a picture that connects to prograde accretion, while the possibility of counterrotation between accretion disk and compact object accounts for observed differences in accreting neutron stars. This picture comes with a surprising twist, which is that neutron stars embody the small-scale analog of FRII quasars, an idea that allows us to complete the scale-invariant picture for the jet-disk connection.

Keywords: X-ray astronomy, Neutron stars, Accretion, Radio jets, Black holes
dHybridR: A Hybrid Particle-in-cell Code Including Relativistic Ion Dynamics. We present the first plasma simulations obtained with the code dHybridR, a hybrid particle-in-cell code with fluid electrons and both thermal and energetic ions that retain relativistic dynamics. dHybridR is constructed to study astrophysical and space-physics problems where a few energetic nonthermal particles (i.e., cosmic rays, CRs) affect the overall dynamics of a nonrelativistic plasma, such as CR-driven instabilities, collisionless shocks, magnetic reconnection, turbulence, etc. In this method paper we provide some applications to linear (resonant/nonresonant CR streaming instability) and strongly nonlinear (parallel shocks) problems that show the capabilities of the code. In particular, we provide the first self-consistent hybrid runs that show the acceleration of relativistic ions at nonrelativistic shocks; CRs develop a power law in momentum, which translates into a broken power law in energy that exhibits a steepening around the ion rest mass, as predicted by the theory of diffusive shock acceleration. We present examples of 2D dHybridR runs relevant for fast shocks in radio supernovae, whose evolution can be followed in real time, and 3D runs of low-Mach-number heliospheric shocks, which can be compared with in situ spacecraft observations.

Keywords: Space plasmas, Plasma physics, Magnetohydrodynamical simulations, Plasma astrophysics, Galactic cosmic rays, Shocks, Cosmic rays
Information in the Reflected-light Spectra of Widely Separated Giant Exoplanets. Giant exoplanets located &gt;1 au away from their parent stars have atmospheric environments cold enough for water or ammonia clouds. We have developed a new equilibrium cloud and reflected-light spectrum model, ExoREL, for widely separated giant exoplanets. The model includes the dissolution of ammonia in liquid-water cloud droplets, an effect studied for the first time for exoplanets. While preserving the causal relationship between temperature and cloud condensation, ExoREL is simple and fast to enable efficient exploration of parameter space. Using the model, we find that the mixing ratio of methane and the cloud top pressure of a giant exoplanet can be uniquely determined from a single observation of its reflected-light spectrum at wavelengths less than 1 μm if it has a cloud deck deeper than ∼0.3 bar. This measurement is enabled by the weak and strong bands of methane and requires a signal-to-noise ratio of 20. The cloud pressure, once derived, provides information about the internal heat flux of the planet. Importantly, we find that for a low, Uranus-like internal heat flux, the planet can have a deep liquid-water cloud, which will sequester ammonia and prevent the formation of the ammonia cloud that would otherwise be the uppermost cloud layer. This newly identified phenomenon causes a strong sensitivity of the cloud top pressure to the internal heat flux. Reflected-light spectroscopy from future direct-imaging missions should therefore not only measure the atmospheric abundances but also characterize the thermal evolution of giant exoplanets.

Keywords: Exoplanet atmospheric composition , Extrasolar ice giants, Exoplanet evolution, Direct imaging, Extrasolar gaseous giant planets
Radiative Properties of Magnetically Arrested Disks. Magnetically arrested disks (MADs) appear when accretion flows are supplied with a sufficient amount of magnetic flux. In this work, we use results of magnetohydrodynamic simulations to set the configuration of the magnetic field and investigate the dynamics and radiative properties of the resulting accretion flow (i.e., without that of the jet) of MADs. The method developed here is applied to both the MAD and the standard and normal evolution (SANE) accretion flow with or without large-scale magnetic fields. For the radiative processes, we include synchrotron, bremsstrahlung, and Compton scattering. We find that, in general, accretion flows of MADs have similar spectra to those of the SANE, which complicates the task of distinguishing MADs from SANEs. At the same accretion rates, MADs are systematically brighter than SANEs. However, the critical accretion rate above which the hot solution ceases to exist is lower in MADs. Consequently, the maximum luminosity an MAD can reach is comparable to but slightly lower than that of SANE, and the dependence on the magnetic flux is weak. We then discuss the implications of our results for active galactic nuclei and accreting black hole binaries.

Keywords: Black hole physics, Magnetohydrodynamics, Radiative magnetohydrodynamics, Galaxy accretion disks, Stellar accretion disks
The Detection of [O III] λ4363 in a Lensed, Dwarf Galaxy at z = 2.59: Testing Metallicity Indicators and Scaling Relations at High Redshift and Low Mass. We present Keck/MOSFIRE (Multi-Object Spectrometer for InfraRed Exploration) and Keck/LRIS (Low Resolution Imaging Spectrometer) spectroscopy of A1689-217, a lensed (magnification ∼7.9), star-forming (SFR ∼ 16 M ⊙ yr-1), dwarf (log(M */M ⊙) = 8.07-8.59) Lyα emitter (EW0 ∼ 138 Å) at z = 2.5918. Dwarf galaxies similar to A1689-217 are common at high redshift and likely responsible for reionization, yet few have been studied with detailed spectroscopy. We report a 4.2σ detection of the electron-temperature-sensitive [O III] λ4363 emission line and use this line to directly measure an oxygen abundance of 12 + log(O/H) = 8.06 ± 0.12 (∼1/4 Z ⊙). A1689-217 is the lowest-mass galaxy at z &gt; 2 with an [O III] λ4363 detection. Using the rest-optical emission lines, we measure A1689-217’s other nebular conditions, including electron temperature (T  e ([O III]) ∼ 14,000 K), electron density (n  e  ∼ 220 cm-3), and reddening (E(B-V) ∼ 0.39). We study relations between strong-line ratios and direct metallicities with A1689-217 and other galaxies with [O III] λ4363 detections at z ∼ 0-3.1, showing that the locally calibrated, oxygen-based, strong-line relations are consistent from z ∼ 0 to 3.1. We also show additional evidence that the O32 versus R23 excitation diagram can be utilized as a redshift-invariant, direct-metallicity-based, oxygen abundance diagnostic out to z ∼ 3.1. From this excitation diagram and the strong-line ratio-metallicity plots, we observe that the ionization parameter at fixed O/H is consistent with no redshift evolution. Although A1689-217 is metal-rich for its M * and star formation rate, we find it to be consistent within the large scatter of the low-mass end of the fundamental metallicity relation. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. These observations are associated with programs #9289, #11710, #11802, #12201, #12931.

Keywords: Dwarf galaxies, Galaxy abundances, Galaxy evolution, Interstellar medium, High-redshift galaxies
Transit Signatures of Inhomogeneous Clouds on Hot Jupiters: Insights from Microphysical Cloud Modeling. We determine the observability in transmission of inhomogeneous cloud cover on the limbs of hot Jupiters through post-processing a general circulation model to include cloud distributions computed using a cloud microphysics model. We find that both the east and west limbs often form clouds, but that the different properties of these clouds enhance the limb-to-limb differences compared to the clear case. Using the James Webb Space Telescope, it should be possible to detect the presence of cloud inhomogeneities by comparing the shape of the transit light curve at multiple wavelengths because inhomogeneous clouds impart a characteristic, wavelength-dependent signature. This method is statistically robust even with limited wavelength coverage, uncertainty on limb-darkening coefficients, and imprecise transit times. We predict that the short-wavelength slope varies strongly with temperature. The hot limbs of the hottest planets form higher-altitude clouds composed of smaller particles, leading to a strong Rayleigh slope. The near-infrared spectral features of clouds are almost always detectable, even when no spectral slope is visible in the optical. In some of our models a spectral window between 5 and 9 μm can be used to probe through the clouds and detect chemical spectral features. Our cloud particle size distributions are not lognormal and differ from species to species. Using the area- or mass-weighted particle size significantly alters the relative strength of the cloud spectral features compared to using the predicted size distribution. Finally, the cloud content of a given planet is sensitive to a species’ desorption energy and contact angle, two parameters that could be constrained experimentally in the future.

Keywords: Exoplanet atmospheres, Planetary atmospheres, Extrasolar gaseous giant planets, Exoplanets
X-Ray Observations of a z ∼ 6.2 Quasar/Galaxy Merger. Quasars at early redshifts (z &gt; 6) with companion galaxies offer unique insights into the growth and evolution of the first supermassive black holes. Here, we report on a 150 ks Chandra observation of PSO J308.0416-21.2339, a z = 6.23 quasar with a merging companion galaxy identified in [C II] and rest-frame UV emission. With {72.3}-8.6+9.6 net counts, we find that PSO J308.0416-21.2339 is powerful ({L}X={2.31}-0.76+1.14× {10}45 {erg} {{{s}}}-1 {cm}}-2 in rest-frame 2.0-10.0 keV) yet soft (spectral power-law index {{Γ }}={2.39}-0.36+0.37 and optical-to-X-ray slope α OX = -1.41 ± 0.11). In addition, we detect three hard-energy photons 2.″0 to the west of the main quasar, cospatial with the brightest UV emission of the merging companion. As no soft-energy photons are detected in the same area, this is potentially indicative of a highly obscured source. With conservative assumptions, and accounting for both background fluctuations and the extended wings of the quasar’s emission, these photons only have a probability P = 0.021 of happening by chance. If confirmed by deeper observations, this system is the first high-redshift quasar and companion individually detected in X-rays and is likely a dual active galactic nucleus.

Keywords: X-ray astronomy, Double quasars, Quasars, Quasar-galaxy pairs, X-ray quasars, Galaxy mergers
Estimating the Molecular Gas Mass of Low-redshift Galaxies from a Combination of Mid-infrared Luminosity and Optical Properties. We present CO (J = 1-0) and/or CO (J = 2-1) spectroscopy for 31 galaxies selected from the ongoing Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, obtained with multiple telescopes. This sample is combined with CO observations from the literature to study the correlation of the CO luminosities ({L}CO(1-0)}) with the mid-infrared luminosities at 12 ({L}12μ {{m}}) and 22 μm ({L}22μ {{m}}), as well as the dependence of the residuals on a variety of galaxy properties. The correlation with {L}12μ {{m}} is tighter and more linear, but galaxies with relatively low stellar masses ({M}* ≲ {10}10 M ⊙) and blue colors (g-r≲ 0.5 and/or NUV - r ≲ 3) fall significantly below the mean {L}CO(1-0)}-{L}12μ {{m}} relation. We propose a new estimator of the CO (1-0) luminosity (and thus the total molecular gas mass M mol) that is a linear combination of three parameters: {L}12μ {{m}}, {M}* , and g - r. We show that, with a scatter of only 0.18 dex in log ({L}CO(1-0)}), this estimator provides unbiased estimates for galaxies of different properties and types. An immediate application of this estimator to a compiled sample of galaxies with only CO (J = 2-1) observations yields a distribution of the CO (J = 2-1) to CO (J = 1-0) luminosity ratios (R21) that agrees well with the distribution of real observations, in terms of both the median and the shape. Application of our estimator to the current MaNGA sample reveals a gas-poor population of galaxies that are predominantly early-type and show no correlation between molecular gas-to-stellar mass ratio and star formation rate, in contrast to gas-rich galaxies. We also provide alternative estimators with similar scatters, based on r- and/or z-band luminosities instead of {M}* . These estimators serve as cheap and convenient M mol proxies to be potentially applied to large samples of galaxies, thus allowing statistical studies of gas-related processes of galaxies.

Keywords: Molecular gas, Infrared photometry, Galaxy evolution, Interstellar medium
NuSTAR Uncovers an Extremely Local Compton-thick AGN in NGC 4968. We present the analysis of Chandra and NuSTAR spectra of NGC 4968, a local (D ∼ 44 Mpc) 12 μm selected Seyfert 2 galaxy, enshrouded within Compton-thick layers of obscuring gas. We find no evidence of variability between the Chandra and NuSTAR observations (separated by 2 yr), nor between the two NuSTAR observations (separated by 10 months). Using self-consistent X-ray models, we rule out the scenario where the obscuring medium is nearly spherical and uniform, contradicting the results implied by the &lt;10 keV Chandra spectrum. The line-of-sight column density, from intervening matter between the source and observer that intercepts the intrinsic active galactic nucleus (AGN) X-ray emission, is well within the Compton-thick regime, with a minimum column density of 2 × 1024 cm-2. The average global column density is high (&gt;3 × 1023 cm-2), with both Compton-thick and Compton-thin solutions permitted, depending on the X-ray spectral model. The spectral models provide a range of intrinsic AGN continuum parameters and implied 2-10 keV luminosities (L 2-10 keV,intrinsic), where the higher end of L 2-10 keV,intrinsic is consistent with expectations from the 12 μm luminosity (L 2-10 keV,intrinisc ∼ 7 × 1042 erg s-1). Compared with Compton-thick AGN previously observed by NuSTAR, NGC 4968 is among the most intrinsically X-ray luminous. However, despite its close proximity and relatively high intrinsic X-ray luminosity, it is undetected by the 105 month Swift-Burst Alert Telescope survey, underscoring the importance of multiwavelength selection for obtaining the most complete census of the most hidden black holes.

Keywords: Seyfert galaxies, X-ray active galactic nuclei, Active galactic nuclei
Submillimeter Signatures from Growing Supermassive Black Holes before Reionization. The presence of supermassive black holes (SMBHs) with masses up to M • ∼ 109 {M}⊙  at redshifts z ≃ 7.5 suggests that their seeds may have started to grow long before the reionization in ambient medium with pristine chemical composition. During their latest 500 Myr episode of growing from z ≥ 10 to z ∼ 7, the black holes shone as luminous as 1011-1012 L ⊙, with a cumulative spectrum consisting of the intrinsic continuum from the hot accretion disk, nebular hydrogen, and helium spectral lines, and the free-free continuum from the gas of host halos. Here we address the question of whether such a plain spectrum would allow us to trace the evolution of these growing SMBHs. In our calculations we assume that host galaxies have stellar populations with masses smaller than the masses of their central black holes—the so-called obese black hole galaxies. Within this model we show that for a sufficiently high mass of gas in a host galaxy—not smaller than the mass of a growing black hole, the cumulative spectrum in the far-infrared reveals a sharp transition from a quasi-blackbody Rayleigh-Jeans spectrum of the black hole ∝λ -2 to a flat free-free nebular continuum λ 0.118 on a longer wavelength limit. Once such a transition in the spectrum is resolved, the black hole mass can be inferred as a combination of the observed wavelength at the transition λ  k  and the corresponding spectral luminosity. The possible observability of this effect in spectra of growing high-z SMBHs and determination of their mass with the upcoming James Webb Space Telescope and the planned space project Spektr-M is briefly discussed.

Keywords: Cosmology, Submillimeter astronomy, Supermassive black holes
The Galaxy Power Spectrum from TGSS ADR1 and the Effect of Flux Calibration Systematics. We explore the large to moderate scale anisotropy in distant radio sources using the TIFR GMRT Sky Survey (TGSS) ADR1 catalog. We use different measures, i.e., number counts, sky brightness, and flux per source, for this study. In agreement with earlier results, we report a significant excess of clustering signal above the angular scale of roughly 10° (i.e., l ⪅ 20-30). We find that some survey areas have a systematically low/high flux and argue this may be the cause of the observed signal of excess power at low multipoles. With mocks we demonstrate the effect of such large-scale flux systematics and recover a TGSS-like excess clustering signal by assuming 20% flux uncertainties over ∼10° × 10° sized patches. We argue that that TGSS at this stage, i.e., TGSS ADR1, is not suitable for large-scale clustering measurements. We find that the measure, flux per source, shows evidence of isotropy for all multipoles l &gt; 2 despite the presence of systematics in the data.

Keywords: Dark matter distribution, Large-scale structure of the universe, Extragalactic radio sources, Active galaxies, Radio galaxies