Sazuna/UAT_keywords huggingface dataset:
Observational Inference on the Delay Time Distribution of Short Gamma-Ray Bursts. The delay time distribution of neutron star mergers provides critical insights into binary evolution processes and the merger rate evolution of compact object binaries. However, current observational constraints on this delay time distribution rely on the small sample of Galactic double neutron stars (with uncertain selection effects), a single multimessenger gravitational wave event, and indirect evidence of neutron star mergers based on r-process enrichment. We use a sample of 68 host galaxies of short gamma-ray bursts to place novel constraints on the delay time distribution and leverage this result to infer the merger rate evolution of compact object binaries containing neutron stars. We recover a power-law slope of $\alpha =-{1.83}_{-0.39}^{+0.35}$ (median and 90% credible interval) with α &lt; -1.31 at 99% credibility, a minimum delay time of ${t}_{\min }={184}_{-79}^{+67}\,\mathrm{Myr}$ with ${t}_{\min }\gt 72\,\mathrm{Myr}$ at 99% credibility, and a maximum delay time constrained to ${t}_{\max }\gt 7.95\,\mathrm{Gyr}$ at 99% credibility. We find these constraints to be broadly consistent with theoretical expectations, although our recovered power-law slope is substantially steeper than the conventional value of α = -1, and our minimum delay time is larger than the typically assumed value of 10 Myr. Pairing this cosmological probe of the fate of compact object binary systems with the Galactic population of double neutron stars will be crucial for understanding the unique selection effects governing both of these populations. In addition to probing a significantly larger redshift regime of neutron star mergers than possible with current gravitational wave detectors, complementing our results with future multimessenger gravitational wave events will also help determine if short gamma-ray bursts ubiquitously result from compact object binary mergers.

Keywords: Gamma-ray bursts, Compact binary stars, Gravitational wave sources
Detection of Intracluster Globular Clusters in the First JWST Images of the Gravitational Lens Cluster SMACS J0723.3-7327 at z = 0.39. We present a survey of globular clusters (GCs) in the massive gravitational lens cluster SMACS J0723.3-7327 at z = 0.39 based on the early released JWST/NIRCam images. In the color-magnitude diagrams of the point sources, we clearly find a rich population of intracluster GCs that are spread over a wide area of the cluster. Their ages, considering the cluster redshift, are younger than 9.5 Gyr. The F200W (AB) magnitudes of these GCs, 26.5 mag &lt; F200W0 &lt; 29.5 mag, correspond to -15.2 mag &lt; M F200W &lt; -12.2 mag, showing that they belong to the brightest GCs (including ultracompact dwarfs). The spatial distributions of these GCs show a megaparsec-scale structure elongated along the major axis of the brightest cluster galaxy. In addition, they show a large number of substructures, some of which are consistent with the substructures seen in the map of diffuse intracluster light. The GC number density map is, in general, consistent with the dark matter mass density map based on the strong lensing analysis in the literature. The radial number density profile of the GCs in the outer region is steeper than the dark matter mass profile obtained from lensing models. These results are consistent with those for the GCs found in the deep HST images of A2744, another massive cluster at z = 0.308, and in simulated galaxy clusters. This shows that the intracluster GCs are an excellent independent tool to probe the dark matter distribution in galaxy clusters, as well as reveal the cluster assembly history in the JWST era.

Keywords: Globular star clusters, Galaxy clusters, Rich galaxy clusters, Giant elliptical galaxies, Intracluster medium, Early-type galaxies
On the Statistics of Elsasser Increments in Solar Wind and Magnetohydrodynamic Turbulence. In this Letter we investigate the dependency with scale of the empirical probability distribution functions (PDF) of Elsasser increments using large sets of WIND data (collected between 1995 and 2017) near 1 au. The empirical PDF are compared to the ones obtained from high-resolution numerical simulations of steadily driven, homogeneous reduced MHD turbulence on a 20483 rectangular mesh. A large statistical sample of Alfvénic increments is obtained by using conditional analysis based on the solar wind average properties. The PDF tails obtained from observations and numerical simulations are found to have exponential behavior in the inertial range, with an exponential decrement that satisfies power laws of the form α  l  ∝ l -μ , where l is the scale size, with μ between 0.17 and 0.25 for observations and 0.43 for simulations. PDF tails were extrapolated assuming their exponential behavior extends to arbitrarily large increments in order to determine structure function scaling laws at very high orders. Our results point to potentially universal scaling laws governing the PDF of Elsasser increments and to an alternative approach to investigate high-order statistics in solar wind observations.

Keywords: Interplanetary turbulence, Magnetohydrodynamics, Solar wind
The Emission Properties of RRAT J0139+3336 at 1.25 GHz. Rotating Radio Transients are a relatively new subclass of pulsar characterized by sporadic bursting emission of single pulses. Here, we present a single-pulse analysis of a rotating radio transient, RRAT J0139+3336, using Five-hundred-meter Aperture Spherical radio Telescope at 1250 MHz. Within 3.32 hr of continuous observation, 152 single pulses were detected in RRAT J0139+3336, with the pulse rate of 45 pulses per hour. We perform a spectral analysis on the single pulses of this pulsar for the first time, finding its mean spectral indices to be -3.2 ± 0.2, which is steeper than most known pulsars. On a single-pulse basis, we produce the first polarimetric profile of this pulsar, which fits well with the rotating vector model. The single pulses are clearly affected by diffractive scintillation with a characteristic scintillation bandwidth of v sc = 28 ± 9 MHz. The pulse energy distribution for RRAT J0139+3336 can be described by a log-normal model.

Keywords: Radio pulsars
An Electron-scattering Time Delay in Black Hole Accretion Disks. Universal to black hole X-ray binaries, the high-frequency soft lag gets longer during the hard-to-intermediate state transition, evolving from ≲1 to ~10 ms. The soft lag production mechanism is thermal disk reprocessing of nonthermal coronal irradiation. X-ray reverberation models account for the light-travel time delay external to the disk, but assume instantaneous reprocessing of the irradiation inside the electron-scattering-dominated disk atmosphere. We model this neglected scattering time delay as a random walk within an α-disk atmosphere, with approximate opacities. To explain soft lag trends, we consider a limiting case of the scattering time delay that we dub the thermalization time delay, t th; this is the time for irradiation to scatter its way down to the effective photosphere, where it gets thermalized, and then scatter its way back out. We demonstrate that t th plausibly evolves from being inconsequential for low mass accretion rates $\dot{m}$ ṁ characteristic of the hard state, to rivaling or exceeding the light-travel time delay for $\dot{m}$ ṁ characteristic of the intermediate state. However, our crude model confines t th to a narrow annulus near peak accretion power dissipation, so cannot yet explain in detail the anomalously long-duration soft lags associated with larger disk radii. We call for time-dependent models with accurate opacities to assess the potential relevance of a scattering delay.

Keywords: Reverberation mapping, X-ray binary stars, Stellar mass black holes
A First Look at the Abundance Pattern-O/H, C/O, and Ne/O-in z &gt; 7 Galaxies with JWST/NIRSpec. We analyze the rest-frame near-UV and optical nebular spectra of three z &gt; 7 galaxies from the Early Release Observations taken with the Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope (JWST). These three high-z galaxies show the detection of several strong emission nebular lines, including the temperature-sensitive [O III] λ4363 line, allowing us to directly determine the nebular conditions and abundances for O/H, C/O, and Ne/O. We derive O/H abundances and ionization parameters that are generally consistent with other recent analyses. We analyze the mass-metallicity relationship (i.e., slope) and its redshift evolution by comparing between the three z &gt; 7 galaxies and local star-forming galaxies. We also detect the C III] λλ1907, 1909 emission in a z &gt; 8 galaxy from which we determine the most distant C/O abundance to date. This valuable detection of log(C/O) = -0.83 ± 0.38 provides the first test of C/O redshift evolution out to high redshift. For neon, we use the high-ionization [Ne III] λ3869 line to measure the first Ne/O abundances at z &gt; 7, finding no evolution in this α-element ratio. We explore the tentative detection of [Fe II] and [Fe III] lines in a z &gt; 8 galaxy, which would indicate a rapid buildup of metals. Importantly, we demonstrate that properly flux-calibrated and higher-S/N spectra are crucial to robustly determine the abundance pattern in z &gt; 7 galaxies with NIRSpec/JWST.

Keywords: Cosmic abundances, Metallicity, Emission line galaxies, Galaxy chemical evolution
A First Look into the Nature of JWST/MIRI 7.7 μm Sources from SMACS 0723. Until now, our knowledge of the extragalactic universe at mid-infrared (mid-IR) wavelengths (&gt;5 μm) was limited to rare active galactic nuclei and the brightest normal galaxies up to z ~ 3. The advent of JWST with its Mid-Infrared Instrument (MIRI) will revolutionize the ability of the mid-IR regime as a key wavelength domain to probe the high-z universe. In this work we present a first study of JWST MIRI 7.7 μm sources selected with &gt;3σ significance from the lensing cluster field SMACS J0723.3-7327. We model their spectral energy distribution (SED) fitting with 13 JWST and Hubble Space Telescope broad bands, in order to obtain photometric redshifts and derived physical parameters for all these sources. We find that this 7.7 μm galaxy sample is mainly composed of normal galaxies up to z = 4 and has a tail of about 2% of sources at higher redshifts to z ≈ 9-10. The vast majority of our galaxies have [3.6]-[7.7] &lt; 0 colors and very few of them need high dust extinction values (A  V  = 3-6 mag) for their SED fitting. The resulting lensing-corrected stellar masses span the range 107-1011 M ⊙. Overall, our results clearly show that the first MIRI 7.7 μm observations of deep fields are already useful to probe the high-redshift universe and suggest that the deeper 7.7 μm observations to be available very soon will open up, for the first time, the epoch of reionization at mid-IR wavelengths.

Keywords: Infrared astronomy, High-redshift galaxies, Redshift surveys
A Segmented Period-Luminosity Relation for Nearby Extragalactic Delta Scuti Stars. The period-luminosity relations (PLRs) of Milky Way δ Scuti (δ Sct) stars have been described to the present day by a linear relation. However, when studying extragalactic systems such as the Magellanic Clouds and several dwarf galaxies, we notice for the first time a nonlinear behavior in the PLR of δ Sct stars. Using the largest sample of ~3700 extragalactic δ Sct stars from data available in the literature-mainly based on the Optical Gravitational Lensing Experiment and the Super MAssive Compact Halo Object project in the Large Magellanic Cloud (LMC) - we obtain that the best fit to the period-luminosity (MV) plane is given by the following piecewise linear relation with a break at logP = -1.03 ± 0.01 (or 0.093 ± 0.002 days) for shorter periods (sp) and longer periods (lp) than the break-point: MV = -7.08(±0.25) logP-5.74(± 0.29); logP&lt;-1.03 MVlp = MVsp +4.38(± 0.32)\cdot (logP+1.03(± 0.01)); logP≥ -1.03. Geometric or depth effects in the LMC, metallicity dependence, or different pulsation modes are discarded as possible causes of this segmented PLR seen in extragalactic δ Sct stars. The origin of the segmented relation at ∼0.09 days remains unexplained based on the current data.

Keywords: Globular star clusters, Delta Scuti variable stars, Dwarf galaxies, Variable stars, SX Phoenicis variable stars
Mid-infrared Polarization of the Diffuse Interstellar Medium toward CygOB2-12. We present the first mid-IR detection of the linear polarization toward the star CygOB2-12, a luminous blue hypergiant that, with A  V  ≈ 10 mag of foreground extinction, is a benchmark in the study of the properties of dust in the diffuse interstellar medium. The 8-13 μm spectropolarimetry, obtained with the CanariCam multimode camera at the Gran Telescopio CANARIAS shows clear trends with wavelength characteristic of silicate grains aligned in the interstellar magnetic field. The maximum polarization, detected with 7.8σ statistical significance near 10.2 μm, is (1.24 ± 0.28)% with position angle 126° ± 8°. We comment on these measurements in the context of recent models for the dust composition in the diffuse interstellar medium.

Keywords: Silicate grains, Spectropolarimetry, Diffuse interstellar clouds
Extreme Mass Loss in Low-mass Type Ib/c Supernova Progenitors. Many core-collapse supernovae (SNe) with hydrogen-poor and low-mass ejecta, such as ultra-stripped SNe and type Ibn SNe, are observed to interact with dense circumstellar material (CSM). These events likely arise from the core collapse of helium stars that have been heavily stripped by a binary companion and have ejected significant mass during the last weeks to years of their lives. In helium star models run to days before core collapse we identify a range of helium core masses ≈2.5-3 M ⊙ whose envelopes expand substantially due to the helium shell burning while the core undergoes neon and oxygen burning. When modeled in binary systems, the rapid expansion of these helium stars induces extremely high rates of late-stage mass transfer ( $\dot{M}\gtrsim {10}^{-2}\,{M}_{\odot }\,{\mathrm{yr}}^{-1}$ Ṁ≳10-2M⊙yr-1 ) beginning weeks to decades before core collapse. We consider two scenarios for producing CSM in these systems: either mass transfer remains stable and mass loss is driven from the system in the vicinity of the accreting companion, or mass transfer becomes unstable and causes a common envelope event (CEE) through which the helium envelope is unbound. The ensuing CSM properties are consistent with the CSM masses (~10-2-1 M ⊙) and radii (~1013-1016 cm) inferred for ultra-stripped SNe and several type Ibn SNe. Furthermore, systems that undergo a CEE could produce short-period neutron star binaries that merge in less than 100 Myr.

Keywords: Binary stars, Core-collapse supernovae, Stellar mass loss, Circumstellar matter, Stellar evolution
Using Anisotropies as a Forensic Tool for Decoding Supernova Remnants. We present a method for analyzing supernova remnants (SNRs) by diagnosing the drivers responsible for structure at different angular scales. First, we perform a suite of hydrodynamic models of the Rayleigh-Taylor instability (RTI) as a supernova (SN) collides with its surrounding medium. Using these models we demonstrate how power spectral analysis can be used to attribute which scales in an SNR are driven by RTI and which must be caused by intrinsic asymmetries in the initial explosion. We predict the power spectrum of turbulence driven by RTI and identify a dominant angular mode that represents the largest scale that efficiently grows via RTI. We find that this dominant mode relates to the density scale height in the ejecta, and therefore reveals the density profile of the SN ejecta. If there is significant structure in an SNR on angular scales larger than this mode, then it is likely caused by anisotropies in the explosion. Structure on angular scales smaller than the dominant mode exhibits a steep scaling with wavenumber, possibly too steep to be consistent with a turbulent cascade, and therefore might be determined by the saturation of RTI at different length scales (although systematic 3D studies are needed to investigate this). We also demonstrate, consistent with previous studies, that this power spectrum is independent of the magnitude and length scales of perturbations in the surrounding medium and therefore this diagnostic is unaffected by "clumpiness" in the circumstellar medium.

Keywords: Supernova remnants, Hydrodynamical simulations, Supernovae, Hydrodynamics
Finding the Missing Baryons in the Intergalactic Medium with Localized Fast Radio Bursts. The missing baryon problem is one of the major unsolved problems in astronomy. Fast radio bursts (FRBs) are bright millisecond pulses with unknown origins. The dispersion measure of FRBs is defined as the electron column density along the line of sight, and accounts for every ionized baryon. Here we measure the baryon content of the universe using 22 localized FRBs. Unlike previous works that fixed the value of dispersion measure of FRB host galaxies and ignored the inhomogeneities of the intergalactic medium (IGM), we use the probability distributions of dispersion measures contributed by host galaxies and IGM from the state-of-the-art IllustrisTNG simulations. We derive the cosmic baryon density of ${{\rm{\Omega }}}_{b}={0.0490}_{-0.0033}^{+0.0036}$ (1σ), with a precision of 7.0%. This value is dramatically consistent with other measurements, such as the cosmic microwave background and Big Bang nucleosynthesis. Our work supports that the baryons are not missing, but residing in the IGM.

Keywords: Intergalactic medium, Baryon density, Radio transient sources
A Circumplanetary Dust Ring May Explain the Extreme Spectral Slope of the 10 Myr Young Exoplanet K2-33b. Young exoplanets are attractive targets for atmospheric characterization to explore the early phase of planetary evolution and the surrounding environment. Recent observations of the 10 Myr young Neptune-sized exoplanet K2-33b revealed that the planet's transit depth drastically decreases from the optical to near-infrared wavelengths. Thao et al. suggested that a thick planetary haze and/or stellar spots may be the cause; however, even the best-fit model only barely explains the data. Here, we propose that the peculiar transmission spectrum may indicate that K2-33b possesses a circumplanetary dust ring; an analog of Jupiter's dust ring. We demonstrate that the ring could produce a steep slope in the transmission spectrum even if its optical depth is as low as ~10-2. We then apply a novel joint atmosphere-ring retrieval to K2-33b and find that the ring scenario could well explain the observed spectrum for various possible ring compositions. Importantly, the dust ring also exhibits prominent ring particle absorption features of ring particles around ~10 μm, whose shape and strength depend on the composition of the ring. Thus, future observations by JWST-MIRI would be able to test not only the ring hypothesis but also, if it indeed exists, to constrain the composition of the ring-providing a unique opportunity to explore the origins of the dust ring around its parent planet, soon after the planetary system's formation.

Keywords: Exoplanet atmospheric composition , Exoplanet rings, Exoplanet atmospheres, Transmission spectroscopy
Polar Dust Emission in Quasar IR SEDs and Its Correlation with Narrow-line Regions. Polar dust has been found to play an important role in the mid-infrared emission of nearby Seyfert nuclei. If and how often polar dust exists among the quasar population is unknown due to the lack of spatially resolved observations. In this Letter, we report correlations between the prominence of active galactic nucleus (AGN) forbidden line emission (commonly associated with the narrow-line region) and the dust mid-IR energy output among the archetypal Palomar-Green quasar sample and other bright type-1 AGNs drawn from the Sloan Digital Sky Survey, Spitzer, and Wide-field Infrared Survey Explorer (WISE) archives. The AGN mid-IR color differences traced by WISE W2 (~4.6 μm)-W3 (~12 μm) and W2 (~4.6 μm)-W4 (~22 μm), and near-IR to mid-IR spectral energy distributions (SEDs) constrained with the Two Micron All Sky Survey, WISE, and Spitzer data have clear trends with the relative strength of the forbidden line regions traced by the optical [O III] and mid-IR [O IV] emission lines. These observations indicate that, where the lines are strong, a large fraction of the AGN emission at λ ≳ 5 μm comes from dust in the forbidden line regions. We find that the widely quoted universal AGN template is a result of averaging quasar SEDs with different levels of polar dust emission above the torus output and that the typical intrinsic IR SED of compact torus dust emission alone falls with increasing wavelength past 5 μm (in νF  ν ). In addition, the association of polar dust with the forbidden lines suggests an alternative to the receding torus hypothesis for the decrease in infrared output with increasing AGN luminosity.

Keywords: Dust continuum emission, Active galactic nuclei, Spectral energy distribution, Quasars
Detecting the Oscillation and Propagation of the Nascent Dynamic Solar Wind Structure at 2.6 Solar Radii Using Very Long Baseline Interferometry Radio Telescopes. Probing the solar corona is crucial to study the coronal heating and solar wind acceleration. However, the transient and inhomogeneous solar wind flows carry large-amplitude inherent Alfvén waves and turbulence, which make detection more difficult. We report the oscillation and propagation of the solar wind at 2.6 solar radii (Rs) by observation of China's Tianwen and ESA's Mars Express with radio telescopes. The observations were carried out on 2021 October 9, when one coronal mass ejection (CME) passed across the ray paths of the telescope beams. We obtain the frequency fluctuations (FFs) of the spacecraft signals from each individual telescope. First, we visually identify the drift of the frequency spikes at a high spatial resolution of thousands of kilometers along the projected baselines. They are used as traces to estimate the solar wind velocity. Then we perform the cross-correlation analysis on the time series of FF from different telescopes. The velocity variations of solar wind structure along radial and tangential directions during the CME passage are obtained. The oscillation of tangential velocity confirms the detection of a streamer wave. Moreover, at the tail of the CME, we detect the propagation of an accelerating fast field-aligned density structure indicating the presence of magnetohydrodynamic waves. This study confirms that the ground-station pairs are able to form particular spatial projection baselines with high resolution and sensitivity to study the detailed propagation of the nascent dynamic solar wind structure.

Keywords: Deep space probes, Very long baseline interferometry, Solar wind
Accretion from Winds of Red Giant Branch Stars May Reveal the Supermassive Black Hole in Leo I. A supermassive black hole (SMBH) of ~3 × 106 M ⊙ was recently detected via dynamical measurements at the center of the dwarf galaxy Leo I. Standing ~2 orders of magnitude above standard scaling relations, this SMBH is hosted by a galaxy devoid of gas and with no significant star formation in the last ~1 Gyr. This detection can profoundly impact the formation models for black holes and their hosts. We propose that winds from a population of ~100 evolved stars within the Bondi radius of the SMBH produce a sizable accretion rate, with Eddington ratios between 9 × 10-8 and 9 × 10-7, depending on the value of the stellar mass loss. These rates are typical of SMBHs accreting in advection-dominated accretion flow mode. The predicted spectrum peaks in the microwaves at ~0.1-1 THz (300-3000 μm) and exhibits significant variations at higher energies depending on the accretion rate. We predict a radio flux of ~0.1 mJy at 6 GHz, mildly dependent on the accretion properties. Deep imaging with Chandra, the Very Large Array, and the Atacama Large Millimeter/submillimeter Array can confirm the presence of this SMBH and constrain its accretion flow.

Keywords: Supermassive black holes, Stellar winds, Dwarf spheroidal galaxies, Red giant stars