Sazuna/UAT_keywords huggingface dataset:
The UNCOVER Survey: First Release of Ultradeep JWST/NIRSpec PRISM Spectra for ∼700 Galaxies from z ∼ 0.3–13 in A2744. We present the design and observations of low-resolution JWST/NIRSpec PRISM spectroscopy from the Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization (UNCOVER) Cycle 1 JWST Treasury program. Targets are selected using JWST/NIRCam photometry from UNCOVER and other programs, and cover a wide range of categories and redshifts to ensure the legacy value of the survey. These categories include the first galaxies at z ≳ 10, faint galaxies during the Epoch of Reionization (z ∼ 6‑8), high-redshift active galactic nuclei (z ≳ 6), Population III star candidates, distant quiescent and dusty galaxies (1 ≲ z ≲ 6), and filler galaxies sampling redshift–color–magnitude space from z ∼ 0.1‑13. Seven NIRSpec microshutter array masks across the extended A2744 cluster were observed, along with NIRCam parallel imaging in nine filters (F090W, F115W, F150W, F200W, F277W, F356W, F410M, F444W, and F480M) over a total area of ∼26 arcmin2, overlapping existing Hubble Space Telescope coverage from programs including the Hubble Frontier Fields and BUFFALO. We successfully observed 553 objects down to mF444W ∼ 30 AB, and by leveraging mask overlaps, we reach total on-target exposure times ranging from 2.4 to 16.7 hr. We demonstrate the success rate and distribution of the confirmed redshifts, and also highlight the rich information revealed by these ultradeep spectra for a subset of our targets. An updated lens model of A2744 is also presented, including 14 additional spectroscopic redshifts and finding a total cluster mass of MSL = (2.1 ± 0.3) × 1015 M⊙. We publicly release reduced 1D and 2D spectra for all objects observed in summer 2023 along with a spectroscopic redshift catalog and the updated lens model of the cluster (https://jwst-uncover.github.io/DR4.html).

Keywords: Galaxy formation, High-redshift galaxies, Galaxy evolution
Measurement of Energy Reduction of Inertial Alfvén Waves Propagating through Parallel Gradients in the Alfvén Speed. We have studied the propagation of inertial Alfvén waves through parallel gradients in the Alfvén speed using the Large Plasma Device at the University of California, Los Angeles. The reflection and transmission of Alfvén waves through inhomogeneities in the background plasma are important for understanding wave propagation, turbulence, and heating in space, laboratory, and astrophysical plasmas. Here we present inertial Alfvén waves under conditions relevant to solar flares and the solar corona. We find that the transmission of the inertial Alfvén waves is reduced as the sharpness of the gradient is increased. Any reflected waves were below the detection limit of our experiment, and reflection cannot account for all of the energy not transmitted through the gradient. Our findings indicate that, for both kinetic and inertial Alfvén waves, the controlling parameter for the transmission of the waves through an Alfvén speed gradient is the ratio of the Alfvén wavelength along the gradient divided by the scale length of the gradient. Furthermore, our results suggest that an as-yet-unidentified damping process occurs in the gradient.

Keywords: Solar flares, Plasma physics, The Sun, Solar coronal heating, Plasma astrophysics, Alfven waves, Solar corona
Challenges in Forming Millisecond Pulsar–Black Holes from Isolated Binaries. Binaries harboring a millisecond pulsar (MSP) and a black hole (BH) are a key observing target for current and upcoming pulsar surveys. We model the formation and evolution of such binaries in isolation at solar metallicity using the next-generation binary population synthesis code POSYDON. We examine neutron star (NS)–BH binaries where the NS forms first (labeled NSBH), as the NS must be able to spin up to MSP rotation periods before the BH forms in these systems. We find that NSBHs are very rare and have a birth rate &lt;1 Myr‑1 for a Milky Way–like galaxy in our typical models. The NSBH formation rate is 2–3 orders of magnitude smaller than that for NS–BH binaries where the BH forms first (labeled BHNS). These rates are also sensitive to model assumptions about the supernova (SN) remnant masses, natal kicks, metallicity, and common-envelope (CE) evolution parameters. We find that 100% of NSBHs undergo a mass ratio reversal before the first SN and up to 52% of NSBHs undergo a double CE phase after the mass ratio reversal occurs. Most importantly, no NSBH binaries in our populations undergo a mass transfer phase, either stable or unstable, after the first SN. This implies that there is no possibility of pulsar spin-up via accretion, and thus MSP–BH binaries cannot form. Thus, dynamical environments and processes may provide the only formation channels for such MSP–BH binaries.

Keywords: Neutron stars, Binary stars, Black holes, Millisecond pulsars, Compact objects
Gas Accretion Traced by Blue-dominated Lyα Emission and Redshifted UV Absorption Lines in Protocluster Galaxies at z = 2.3 from the KBSS-KCWI Survey. Lyα emission with a dominant blueshifted peak can probe gas flowing through the circumgalactic medium as it accretes onto galaxies and fuels new star formation, although it has seldom actually been observed. Here we present new Keck Cosmic Web Imager observations of the extended Lyα halos surrounding Q1700-BX710 and Q1700-BX711, a pair of UV continuum-selected Keck Baryonic Structure Survey galaxies at z = 2.3 in the HS1700+643 protocluster. We find that BX710's and BX711's Lyα halos are aligned with a large-scale galaxy filament consisting of 13 spectroscopically identified protocluster galaxies. By measuring the peak separation and blue-to-red peak flux ratio of the Lyα emission profiles throughout these galaxies' Lyα halos, we have obtained measurements of their spatially varying velocity structure. The prevalence of blue-dominated Lyα emission profiles throughout BX711's Lyα halo suggests actively accreting gas. We fit a clumpy, multiphase Monte Carlo Radiative Transfer model, which assumes a radially varying clump velocity to the spatially resolved Lyα emission throughout BX710's and BX711's Lyα halos and simultaneously fit these galaxies' average down-the-barrel UV absorption profile with a radially varying velocity model. The results of these models are consistent with a combination of H I and higher-metallicity gas accretion for both galaxies, especially BX711, which exhibits inflow-driven kinematics throughout most of its Lyα halo. We consider various accretion scenarios to explain these findings, including accretion of metal-enriched gas from the cosmic web, galaxy interactions, and recycled gas from the circumgalactic medium, all of which are compatible with our current observations. *This paper presents findings from observations conducted at the W.M. Keck Observatory, which is operated as a scientific partner ship 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. †The HST/ACS observations presented in this paper are available on the Space Telescope Science Institute's Mikulski Archive for Space Telescopes (MAST) at doi: 10.17909/j2mb-9350.

Keywords: Galaxy formation, Large-scale structure of the universe, Protoclusters, Galaxy pairs, Galaxy evolution, Circumgalactic medium
Deep Neural Emulation of the Supermassive Black Hole Binary Population. While supermassive black hole (SMBH) binaries are not the only viable source for the low-frequency gravitational wave background (GWB) signal evidenced by the most recent pulsar timing array (PTA) data sets, they are expected to be the most likely. Thus, connecting the measured PTA GWB spectrum and the underlying physics governing the demographics and dynamics of SMBH binaries is extremely important. Previously, Gaussian processes (GPs) and dense neural networks have been used to make such a connection by being built as conditional emulators; their input is some selected evolution or environmental SMBH binary parameters and their output is the emulated mean and standard deviation of the GWB strain ensemble distribution over many Universes. In this paper, we use a normalizing flow (NF) emulator that is trained on the entirety of the GWB strain ensemble distribution, rather than only mean and standard deviation. As a result, we can predict strain distributions that mirror underlying simulations very closely while also capturing frequency covariances in the strain distributions as well as statistical complexities such as tails, non-Gaussianities, and multimodalities that are otherwise not learnable by existing techniques. In particular, we feature various comparisons between the NF-based emulator and the GP approach used extensively in past efforts. Our analyses conclude that the NF-based emulator not only outperforms GPs in the ease and computational cost of training but also outperforms in the fidelity of the emulated GWB strain ensemble distributions.

Keywords: Supermassive black holes, Neural networks, Millisecond pulsars, Gravitational wave astronomy, Gravitational waves
Laboratory Measurements of n &gt;= 3 K-shell Transition Energies of Sulfur Ions from F-like S VIII to Li-like S XIV. Inner-shell transitions are ubiquitous in nonequilibrium collisionally ionized plasmas, such as supernova remnants, and in photoionized plasmas, such as outflows from active galactic nuclei and X-ray binaries. Inner-shell X-ray emission can help determine key parameters of these systems, such as ionization time, τ, and ionization parameter, ξ. Despite their importance, only theoretical inner-shell transition energies are available for many ions. To provide experimental benchmarks, we have measured the dominant n → 1 K-shell transitions of sulfur ions where n ≥ 3 from Li-like S XIV to F-like S VIII using LLNL's SuperEBIT electron beam ion trap and the NASA/GSFC EBIT Calorimeter Spectrometer (ECS). We identify over 30 spectral features and measure their energies with uncertainties in the ∼0.1–1 eV range. We compare these results to Flexible Atomic Code (FAC) and multireference Møller–Plesset (MR-MP) calculations and find differences between theory and experiment of ∼1 eV for FAC and &lt;0.5 eV for most MR-MP calculations. We also compare these results to two widely used atomic databases, AtomDB and CHIANTI, and find discrepancies as high as 7 eV. Furthermore, many transitions are missing from these databases despite being prominent in our data.

Keywords: High energy astrophysics, Atomic physics, Experimental data, Laboratory astrophysics, Atomic data benchmarking
Effect of Viewing Angle in Gamma-Ray Burst Properties. The empirical classification of gamma-ray bursts (GRBs) is based on their distribution in the plane of burst duration and spectral hardness. Two distinct distributions, long-soft and short-hard bursts, are observed in this plane, forming the basis for the long and short classification scheme. Traditionally, this scheme was mapped to two different GRB progenitor classes. However, several recent bursts have challenged this mapping. This work investigates how an observer's viewing angle relative to the jet axis influences the duration-hardness plane. We simulate single-pulse GRBs using an optically and geometrically thin homogeneous top-hat jet model. Bursts are simulated with an isotropic viewing angle distribution, and we calculate the pulse duration and spectral hardness corresponding to FERMI GBM energy bands. The viewing angle significantly impacts spectral hardness for our assumed broken power-law spectra, while its effect on duration is less pronounced. Our analysis indicates that soft and low-luminous bursts are likely off-axis events. It is possible that some of the fast X-ray transients and X-ray-rich GRBs observed by the Einstein Probe and the Space Variable Objects Monitor missions originate from off-axis jets.

Keywords: Gamma-ray bursts, Relativistic jets
A Simplified Theory of External Occulters for Solar Coronagraphs. We present a first-principles analytic treatment of modern multivane occulters in circular (coronagraph) and linear (heliospheric imager) geometry, develop a simplified theory that is useful for designing and predicting their performance, explain certain visual artifacts, and explore the performance limits of multivane occulters. Multivane occulters are challenging to design in part because they violate the conditions for both the Fraunhofer and Fresnel approximations to diffraction theory, and new designs have therefore generally required explicit simulation, empirical measurement, "guesstimation," or all three. Starting from the Kirchoff diffraction integral, we develop a "successive plane-wave" approximate analytic theory that is suitable for predicting the performance of multivane occulters, and use it to derive closed-form expressions for the performance of new designs. We review the fundamental 2D system of an occulter edge, discuss how it applies to real 3D systems by extrusion or revolution, present the reason for observed bright quasi-achromatic fringing around coronagraph occulters, develop the successive plane wave approximation in 2D and explore its limits, describe the relevance of the 2D theory to practical 3D instruments, and discuss implications for multivane occulter design in current and future instruments.

Keywords: Space vehicle instruments, Optical observation, Coronagraphic imaging, Astronomical instrumentation, Solar instruments
Hinode/EIS Observation of the Alfvénic Fluctuations in the Quiet Sun. Alfvénic fluctuations in the corona are regularly observed in EUV imaging and infrared spectroscopic data. We report here on the Doppler velocity fluctuations within the data from the Extreme-Ultraviolet Imaging Spectrometer (EIS) on board Hinode. The capabilities of EIS provide an opportunity to detect fluctuations in the solar atmosphere and confirm the previous results from ground-based spectroscopic data using EIS's EUV spectra and in seeing-free conditions. We analyzed Doppler velocity time series for a particular date of observation, 2007 September 27, above the limb. The Fourier transform of the observed signals show the Doppler velocity has a broad spectrum distributed as a power law with a power enhancement around 3–4 mHz. This result is consistent with previous observational results obtained with Coronal Multi-Channel Polarimeter data, and hence we interpret the Doppler velocity fluctuations as Alfvénic in nature. We performed nonlinear regression on the power spectra to determine the index of the power law and to parameterize the properties of the enhancement. We find good agreement between the estimated values and those from previous studies. Furthermore, correlation analysis shows that the observed oscillations are spatially coherent perpendicular to the magnetic field on the length scale L⊥ ∼ 8 Mm, providing an estimate on the energy injection scale of a bundle of coherently oscillating loops.

Keywords: Solar oscillations, Quiet solar corona
Ejecta Wakes from Companion Interaction in Type Ia Supernova Remnants. Type Ia supernovae are triggered by accretion onto a white dwarf from a companion that is most likely Roche lobe–filling at the time of the explosion. The collision between the ejecta and a surviving companion carves out a conical wake, which could manifest as an asymmetry when the ejecta reaches the remnant phase. We simulate the companion interaction using the Athena++ hydrodynamics solver to determine the ejecta structure for a double-degenerate type Ia supernova. Ejecta in the wake is of lower density and higher velocity than the unperturbed ejecta. We then evolve the ejecta for several thousand years using the expanding-grid code Sprout. The forward shock within the wake is initially indented, but becomes spherical after roughly a thousand years due to transverse motion of shocked ejecta that fills the wake. The reverse shock travels quickly within the wake, leading to an off-center convergence of the reverse shock and leaving the remnant with an asymmetrical core. This also draws material from the interstellar medium deep into the remnant, eventually reaching the center. Large Rayleigh–Taylor plumes are found around the edge of the wake, creating a toroidal structure composed primarily of ejecta. Estimates of the thermal X-ray emission show that such remnants exhibit observable asymmetries for thousands of years.

Keywords: Supernova remnants, Type Ia supernovae, Hydrodynamics
Tidal Disruption of "Snow Clouds" by Unassociated Stars. It has been suggested that star-forming galaxies may host a substantial, dark reservoir of gas in the form of planetary-mass molecular clouds that are so cold that H2 can condense. Here we investigate the process of tidal disruption of such "snow clouds" by close passage of field stars. We construct a suite of simulations using the hydrodynamic formalism introduced by Carter and Luminet, and use it to explore the properties of the resulting tidal debris. The debris streams are tiny structures that are highly over-pressured relative to the ambient interstellar medium (ISM). They are also unusual in their composition—initially consisting of cold, gaseous He together with H2 "snowballs" that may be as much as a meter in size. Each stream expands and cools and is subsequently shocked as it plows through the ISM; the snowballs are gradually eroded by the shocked gas. Snowballs streaming through the shocked ISM create microstructured plasma that is somewhat reminiscent of the "scattering screens" revealed by radio-wave scintillation studies. However, the tidal disruption rate is too low to account for the observed number of scattering screens if, as we assume here, the stars and clouds have no prior physical association so that disruptions occur as a result of chance encounters between stars and clouds.

Keywords: Hydrodynamics, Plasma clouds, Molecular clouds, Interstellar clouds, Interstellar medium, Interstellar scintillation, Interstellar scattering
ALMA Reveals Thermal and Nonthermal Desorption of Methanol Ice in the HD 100546 Protoplanetary Disk. Methanol (CH3OH) and formaldehyde (H2CO) are chemically coupled organic molecules proposed to act as an intermediate step between simple molecules and more complex prebiotic compounds. Their abundance distributions across disks regulate the prebiotic potential of material at different disk radii. We present observations of multiple methanol and formaldehyde transitions toward the Herbig Ae disk HD 100546 obtained with the Atacama Large Millimeter/submillimeter Array, building upon the previous serendipitous detection of methanol in this source. We find that methanol has a higher rotational temperature (Trot) than formaldehyde toward both the centrally concentrated emission component in the inner disk (0─110 au) and a radially separate dust ring farther out in the disk (180─260 au). Trot decreases for methanol and formaldehyde from the inner (  K and   K) to the outer disk (  K and   K), suggesting that we are tracing two different chemical environments. Trot for both species in the inner disk is consistent with thermal desorption as the origin, while the outer disk reservoir is driven by nonthermal desorption. The CH3OH/H2CO column density ratio decreases from   in the inner disk to   in the outer disk, consistent with modeling predictions. The CH3OH/H2CO column density ratio for the inner disk is consistent with the median value in the range of column density ratios compiled from solar system comets, which would have formed at a similar distance. This supports the notion that interstellar ice is inherited and preserved by protoplanetary disks around solar-mass and intermediate-mass stars as we are seeing "fresh" ice sublimation, as well as providing more evidence for the presence of prebiotic precursor molecules in planet-forming regions.

Keywords: Herbig Ae/Be stars, Protoplanetary disks, Complex organic molecules, Astrochemistry
On the Number of Confirmed Pulsar Planets: The Rule of Six. Since the first definitive exoplanet detection, the three planets around millisecond radio pulsar PSR B1257+12, few more pulsar planets (PPs) have been reported. The peer-reviewed literature is ambiguous about the identity of confirmed PPs, with the number 6 appearing repeatedly, although it is generally not the same six listed pulsars or planets. We examined all claims, finding eight confirmed planets distributed among six pulsars. These objects overlap with the black widow pulsar population, there being 12 millisecond pulsars with credible companion masses below 10 Jupiter masses and little reason to choose between them. If, on the other hand, evidence for a planetary disk origin were adopted as a defining criterion, then only PSR B1257+12 with its three planets would qualify. Other claimed PP candidates have been either retracted, ruled out by subsequent studies, doubted because of mutually exclusive planetary solutions, or based on alternative theories. Long-lived quasiperiodic timing residuals are major culprits with several claimed orbital periods closely matching the data durations. Widely used exoplanet repositories differ in their inclusion criteria for PPs, resulting in large numerical discrepancies ranging from 6/8 confirmed pulsars/planets (NASA Exoplanet Archive) to 71/74 (Extrasolar Planets Encyclopaedia), which more importantly obscure a crucial distinction between planetary systems and ablated low-mass substellar companions. Tentative evidence for a spin–orbit correlation is found for the confirmed PPs, whereas such coupling is ruled out for black widows as a class. Surveys show PPs are extremely rare, yet their existence and physical properties present major challenges to understanding supernova explosions and planet formation around millisecond pulsars.

Keywords: Pulsar planets
Early Time Small-scale Structures in Hot Exoplanet Atmosphere Simulations. We report on the critical influence of small-scale flow structures (e.g., fronts, vortices, and waves) that immediately arise in hot exoplanet atmosphere simulations initialized with a resting state. A hot, 1:1 spin–orbit synchronized Jupiter is used here as a clear example; but, the phenomenon is generic and important for any type of a hot synchronized planet—gaseous, oceanic, or telluric. When the early time structures are not captured in simulations (due to, e.g., poor resolution and/or too much dissipation), the flow behavior is markedly different at later times, in an observationally significant way; for example, the flow at large scales is smoother and much less dynamic. This results in the temperature field, and its corresponding thermal flux, to be incorrectly predicted in numerical simulations, even when the quantities are spatially averaged.

Keywords: Hydrodynamical simulations, Exoplanets, Hydrodynamics, Exoplanet atmospheric dynamics, Hot Jupiters, Exoplanet atmospheric variability, Planetary atmospheres, Planetary climates, Atmospheric dynamics, Exoplanet atmospheres