Sazuna/UAT_keywords huggingface dataset:
A JWST Project on 47 Tucanae. Overview, Photometry, and Early Spectroscopic Results of M Dwarfs and Observations of Brown Dwarfs. James Webb Space Telescope (JWST) observations have been demonstrated to be efficient in detecting multiple stellar populations in globular clusters (GCs) in the low-mass regime of M dwarfs. We present an overview, and first results, of different projects that can be explored by using the JWST observations gathered under program GO2560 for 47 Tucanae, the first program entirely devoted to the investigation of multiple populations in very-low-mass stars, which includes spectroscopic data for the faintest GC stars for which spectra are available. Our color–magnitude diagram (CMD) shows some substructures for ultracool stars, including gaps and breaks in slope. In particular, we observe both a gap and a minimum in the F322W2 luminosity function less than 1 mag apart, and discuss which it could be associated with the H-burning limit. We detect stars fainter than this minimum, very likely brown dwarfs. We corroborate the ubiquity of the multiple populations across different masses, from ∼0.1 M ⊙ up to red giants (∼0.8 M ⊙). The oxygen range inferred for the M dwarfs, both from the CMD and from the spectra of two M dwarfs associated with different populations, is similar to that observed for giants. We have not detected any difference between the fractions of stars in distinct populations across stellar masses ≳ 0.1 M ⊙. This work demonstrates the JWST's capability in uncovering multiple populations within M dwarfs and illustrates the possibility to analyze very-low-mass stars in GCs approaching the H-burning limit and the brown-dwarf sequence. *The main data set presented in this article was obtained from the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute. The specific observations analyzed can be accessed via doi:10.17909/6t82-4360.

Keywords: M dwarf stars, Population II stars, CCD photometry
Adjusting the Potential Field Source Surface Height Based on Magnetohydrodynamic Simulations. A potential field solution is widely used to extrapolate the coronal magnetic field above the Sun's surface to a certain height. This model applies the current-free approximation and assumes that the magnetic field is entirely radial beyond the source surface height, which is defined as the radial distance from the center of the Sun. Even though the source surface is commonly specified at 2.5 R  s  (solar radii), previous studies have suggested that this value is not optimal in all cases. In this study, we propose a novel approach to specify the source surface height by comparing the areas of the open magnetic field regions from the potential field solution with predictions made by a magnetohydrodynamic model, in our case the Alfvén Wave Solar atmosphere Model. We find that the adjusted source surface height is significantly less than 2.5 R  s  near solar minimum and slightly larger than 2.5 R  s  near solar maximum. We also report that the adjusted source surface height can provide a better open flux agreement with the observations near the solar minimum, while the comparison near the solar maximum is slightly worse.

Keywords: Solar cycle, Magnetohydrodynamics, Solar magnetic fields
The Awakening of a Blazar at Redshift 2.7 Temporally Coincident with the Arrival of Cospatial Neutrino Event IceCube-201221A. We report on multiwavelength studies of a blazar NVSS J171822+423948, which is identified as the low-energy counterpart of 4FGL J1718.5+4237, the unique γ-ray source known to be cospatial with the IceCube neutrino event IC-201221A. After a 12 yr long quiescent period undetected by Fermi-LAT, γ-ray activities with a tenfold flux increase emerge soon (a few tens of days) after the arrival of the neutrino. Associated optical flares in the Zwicky Transient Facility g, r, and i bands are observed together with elevated Wide-field Infrared Survey Explorer infrared fluxes. Synchronized variations suggest that both the γ-ray emission and the neutrino event are connected to the blazar. Furthermore, the optical spectrum reveals emission lines at a redshift z = 2.68 ± 0.01. Thus, it is the first candidate for a neutrino-emitting blazar at the redshift above 2. Discussions of theoretical constraints of neutrino production and comparisons with other candidates are presented.

Keywords: Radio loud quasars, Neutrino astronomy, Gamma-ray sources, Galaxy jets
New Light on Dark Extended Lenses with the Roman Space Telescope. The Roman Space Telescope's Galactic Bulge Time Domain Survey will constitute the most sensitive microlensing survey of the Galactic bulge to date, opening up new opportunities to search for dark matter (DM). Many extensions of the Standard Model predict the formation of extended DM substructures, such as DM subhalos, boson/axion stars, and halo-dressed primordial black holes. We demonstrate that for such targets, Roman will be sensitive to a broad parameter space up to 4 orders of magnitude below existing constraints. Our analysis can be readily applied to other extended DM configurations as well.

Keywords: Gravitational microlensing, Dark matter
Discovery of Merging Twin Quasars at z = 6.05. We report the discovery of two quasars at a redshift of z = 6.05 in the process of merging. They were serendipitously discovered from the deep multiband imaging data collected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. The quasars, HSC J121503.42−014858.7 (C1) and HSC J121503.55−014859.3 (C2), both have luminous (&gt;1043 erg s−1) Lyα emission with a clear broad component (full width at half maximum &gt;1000 km s−1). The rest-frame ultraviolet (UV) absolute magnitudes are M 1450 = − 23.106 ± 0.017 (C1) and −22.662 ± 0.024 (C2). Our crude estimates of the black hole masses provide $\mathrm{log}({M}_{\mathrm{BH}}/{M}_{\odot })=8.1\pm 0.3$ in both sources. The two quasars are separated by 12 kpc in projected proper distance, bridged by a structure in the rest-UV light suggesting that they are undergoing a merger. This pair is one of the most distant merging quasars reported to date, providing crucial insight into galaxy and black hole build-up in the hierarchical structure formation scenario. A companion paper will present the gas and dust properties captured by Atacama Large Millimeter/submillimeter Array observations, which provide additional evidence for and detailed measurements of the merger, and also demonstrate that the two sources are not gravitationally lensed images of a single quasar.

Keywords: Double quasars, Supermassive black holes, Quasars, Active galactic nuclei, Galaxy mergers, Reionization, High-redshift galaxies
3D Magnetic Free Energy and Flaring Activity Using 83 Major Solar Flares. In this Letter, we examine the relationship between 3D magnetic free energy (MFE) and flaring activity using 83 major solar flares (M-class and X-class) in nine solar active regions (ARs). For this, we use 998 nonlinear force-free field extrapolations compiled by the "Institute for Space-Earth Environmental Research Database" at Nagoya University. These ARs produced at least three major flares with distinct rising and peak phases of 3D MFE. For each phase, the solar flare occurrence rate (FOR) is calculated as a ratio of the number of flares to the duration. The major results from this study are summarized as follows. First, there is no clear linear correlation (CC = 0.15) between 3D MFE and flare peak flux. Second, the FOR (3.4 day‑1) of the rising phase is a little higher than that (3.1 day‑1) of the peak phase, depending on AR. Third, for several flares, there are noticeable decreases in 3D MFE, which correspond to the typical energy of a major flare (about 1032 erg). Fourth, it is interesting to note that there are noticeable enhancements in FORs at several local maxima of 3D MFE, which may be associated with flux emergence and/or shearing motions. Fifth, the flare index rates, which are defined as the summation of flaring activity divided by the duration, of rising and peak phases are 151 day‑1 and 314 day‑1, respectively. Our results imply that the traditional and simple "storage and release" model does not apply to flare activities, and the random perturbation may be important for triggering flares.

Keywords: Solar flares, Solar magnetic flux emergence, The Sun, Solar active regions, Solar magnetic fields
The Next Generation Deep Extragalactic Exploratory Public (NGDEEP) Survey. We present the Next Generation Deep Extragalactic Exploratory Public (NGDEEP) Survey, a deep slitless spectroscopic and imaging Cycle 1 JWST treasury survey designed to constrain feedback mechanisms in low-mass galaxies across cosmic time. NGDEEP targets the Hubble Ultra Deep Field (HUDF) with NIRISS slitless spectroscopy ( ${f}_{\mathrm{lim},\mathrm{line},5\sigma }\approx 1.2\,\times \,$ 10‑18 erg s‑1 cm‑2) to measure metallicities and star formation rates (SFRs) for low-mass galaxies through the peak of the cosmic SFR density (0.5 &lt; z &lt; 4). In parallel, NGDEEP targets the HUDF-Par2 parallel field with NIRCam ( ${m}_{\mathrm{lim},5\sigma }=30.6-30.9$ ) to discover galaxies to z &gt; 12, constraining the slope of the faint end of the rest-ultraviolet luminosity function. NGDEEP overlaps with the deepest HST Advanced Camera for Surveys optical imaging in the sky, F435W in the HUDF ( ${m}_{\mathrm{lim},{\rm{F}}435{\rm{W}}}=29.6$ ) and F814W in HUDF-Par2 ( ${m}_{\mathrm{lim},{\rm{F}}814{\rm{W}}}=30$ ), making this a premier HST+JWST deep field. As a treasury survey, NGDEEP data are public immediately, and we will rapidly release data products and catalogs in the spirit of previous deep-field initiatives. In this paper we present the NGDEEP survey design, summarize the science goals, and detail plans for the public release of NGDEEP reduced data products.

Keywords: Early universe, Galaxy formation, Galaxy evolution, Galaxy chemical evolution
Recovery of High-energy Low-frequency Quasiperiodic Oscillations from Black Hole X-Ray Binary MAXI J1535–571 with a Hilbert–Huang Transform Method. We propose a method based on the Hilbert–Huang transform (HHT) to recover the high-energy waveform of low-frequency quasiperiodic oscillations (QPOs). Based on the method, we successfully obtain the modulation of the phase-folded light curve above 170 keV using the QPO phase reconstructed at lower energies in MAXI J1535–571 with Insight-HXMT observations. A comprehensive simulation study is conducted to demonstrate that such modulation indeed originates from the QPO. Thus, the highest energies turn out to significantly exceed the upper limit of ∼100 keV for QPOs reported previously using the Fourier method, marking the first opportunity to study QPO properties above 100 keV in this source. Detailed analyses of these high-energy QPO profiles reveal different QPO properties between the 30–100 and 100–200 keV energy ranges: the phase lag remains relatively stable, and the amplitude slightly increases below ∼100 keV, whereas above this threshold, soft phase lags and a decrease in amplitude are observed. Given the reports of a hard-tail detection in broad spectroscopy, we propose that the newly discovered QPO properties above 100 keV are dominated by the hard-tail component, possibly stemming from a relativistic jet. Our findings also indicate a strong correlation between the QPOs originating from the jet and corona, supporting the scenario of jet–corona coupling precession. We emphasize that our proposed HHT-based method can serve as an efficient manner in expanding the high-energy band for studying QPOs, thereby enhancing our understanding of their origin.

Keywords: Accretion, Black hole physics, X-ray binary stars
A Unifying Model of Mixed Inertial Modes in the Sun. We present an analytical model that unifies many of the inertial waves that have been recently observed on the surface of the Sun, as well as many other modes that have been theoretically predicted—but have yet to be observed—into a single family of mixed inertial modes. By mixed, we mean that the prograde- and retrograde-propagating members of this family have different restoring forces and hence different behavior. Thermal Rossby waves exist as prograde-propagating waves, while the high-frequency retrograde (HFR) wave is one example of a member of the retrograde branch. This family of mixed modes has fully 3D motions that satisfy the anelastic form of the continuity condition. As such, the horizontal velocity is both vortical and divergent with the later flow component associated with a dynamically important radial velocity. The modes are differentiated by the number of nodes in latitude, with the lowest latitudinal order corresponding to the traditional thermal Rossby wave of Busse, the first latitudinal overtone to the mixed mode of Bekki et al., and the second overtone to the HFR wave discovered by Hanson et al. There also exist infinitely more modes of higher latitudinal order whose frequencies increase as the order increases. These higher overtones may correspond to many of the inertial modes that have been recently identified by numerical eigenmode solvers.

Keywords: Internal waves, Solar interior, Hydrodynamics, Solar convective zone, Stellar oscillations, Astrophysical fluid dynamics
On the Chemical and Kinematic Signatures of the Resonances of the Galactic Bar as Revealed by the LAMOST-APOGEE Red Clump Stars. The Milky Way is widely considered to exhibit features of a rotational bar or quadrupole bar. In either case, the feature of the resonance of the Galactic bar should be present in the properties of the chemistry and kinematics, over a large area of the disk. With a sample of over 170,000 red clump stars from LAMOST-APOGEE data, we attempt to detect the chemical and kinematic signatures of the resonances of the Galactic bar, within 4.0 ≤ R ≤ 15.0 kpc and ∣Z∣ ≤ 3.0 kpc. The measurement of the Δ[Fe/H]/Δ∣Z∣–R with subtracted global profiles trends shows that the thin and thick disks values are Cor_Δ[Fe/H]/Δ∣Z∣ = 0.010 sin (1.598 R + 2.551) and Cor_Δ[Fe/H]/Δ∣Z∣ = 0.006 sin (1.258 R ‑ 0.019), respectively. The analysis of the tilt angle of the velocity ellipsoid indicates that the thin and thick disks are accurately described as α = α 0 arctan (Z/R), with ${\alpha }_{0}=0.198\,\sin $ (0.853 R + 1.982) + 0.630 and ${\alpha }_{0}=0.220\,\sin $ (0.884 R + 2.012) + 0.679 for thin and thick disks, respectively. These periodic oscillations in Cor_Δ[Fe/H]/Δ∣Z∣ and α 0 with R appear in both thin and thick disks are the most likely chemical and kinematic signatures of the resonance of the Galactic bar. The difference in the phase of the functions of the fitted periodic oscillations for the thin and thick disks may be related to the presence of a second Galactic bar.

Keywords: Stellar kinematics, Milky Way disk, Dynamical evolution, Galactic bar
Discovery of a Rare Eclipsing Be/X-Ray Binary System, Swift J010902.6-723710 = SXP 182. We report on the discovery of Swift J010902.6-723710, a rare eclipsing Be/X-ray Binary system by the Swift SMC Survey (S-CUBED). Swift J010902.6-723710 was discovered via weekly S-CUBED monitoring observations when it was observed to enter a state of X-ray outburst on 2023 October 10. X-ray emission was found to be modulated by a 182 s period. Optical spectroscopy is used to confirm the presence of a highly inclined circumstellar disk surrounding a B0-0.5Ve optical companion. Historical UV and IR photometry is then used to identify strong eclipse-like features reoccurring in both light curves with a 60.623 day period, which is adopted as the orbital period of the system. Eclipsing behavior is found to be the result of a large accretion disk surrounding the neutron star. Eclipses are produced when the disk passes in front of the OBe companion, blocking light from both the stellar surface and circumstellar disk. This is only the third Be/X-ray binary to have confirmed eclipses. We note that this rare behavior provides an important opportunity to constrain the physical parameters of a Be/X-ray binary with greater accuracy than is possible in noneclipsing systems.

Keywords: X-ray binary stars, High energy astrophysics, Massive stars, High mass x-ray binary stars, Eclipsing binary stars
Model-independent Way to Determine the Hubble Constant and the Curvature from the Phase Shift of Gravitational Waves with DECIGO. In this Letter, we propose a model-independent method to determine the Hubble constant and curvature simultaneously by taking advantage of the possibilities of future spaceborne gravitational-wave detector DECIGO in combination with the radio quasars as standard rulers. Similarly to the redshift drift in the electromagnetic domain, accelerating expansion of the Universe causes a characteristic phase correction to the gravitational waveform detectable by DECIGO. Hence, one would be able to extract the Hubble parameter H(z). This could be used to recover a distance–redshift relation supported by the data not relying on any specific cosmological model. Assuming the FLRW metric and using intermediate-luminosity radio quasars as standard rulers, one achieves an interesting opportunity to directly assess the H 0 and Ω k  parameters. To test this method, we simulated a set of acceleration parameters achievable by future DECIGO. Based on the existing sample of 120 intermediate-luminosity radio quasars calibrated as standard rulers, we simulated much bigger samples of such standard rulers possible to obtain with very long baseline interferometry (VLBI). In the case of (N = 100) of radio quasars, which is the size of the currently available sample, the precision of the cosmological parameters determined would be ${\sigma }_{{H}_{0}}=2.74$ km s‑1 Mpc‑1 and ${\sigma }_{{{\rm{\Omega }}}_{k}}=0.175$ . In the optimistic scenario (N = 1000) achievable by VLBI, the precision of H 0 would be improved to 1%, which is comparable to the result of ${\sigma }_{{H}_{0}}=0.54$ km s‑1 Mpc‑1 from Planck 2018 TT, TE, EE+lowE+lensing data, and the precision of Ω k  would be 0.050. Our results demonstrate that such combined analysis, possible in the future, could be helpful in solving the current cosmological issues concerning the Hubble tension and cosmic curvature tension.

Keywords: Hubble constant, Observational cosmology, Cosmological parameters
Drivers of Magnetic Field Amplification at Oblique Shocks: In Situ Observations. Collisionless shocks are ubiquitous structures throughout the Universe. Shock waves in space and astrophysical plasmas convert the energy of a fast-flowing plasma to other forms of energy, including thermal and magnetic energies. Plasma turbulence and high-amplitude electric and magnetic fluctuations are necessary for effective energy conversion and particle acceleration. We survey and characterize in situ observations of reflected ions and magnetic field amplification rates at quasiperpendicular shocks under a wide range of upstream conditions. We report magnetic amplification rates as high as 25 in our current data set. Reflected ions interacting with the incoming plasma create magnetic perturbations that cause magnetic amplification in upstream and downstream regions of quasiperpendicular shocks. Our observations show that, in general, magnetic amplification increases with the fraction of reflected ions, which itself increases with Mach number. Both parameters plateau once full reflection is reached. Magnetic amplification continuously increases with the inverse of the magnetization parameter of the upstream plasma. We find that the extended foot region upstream of shocks and nonlinear processes within that region are key factors for intense magnetic amplification. Our observations at nonrelativistic shocks provide the first experimental evidence that below a certain magnetization threshold, the magnetic amplification efficiency at quasiperpendicular shocks becomes comparable to that at the quasiparallel shocks.

Keywords: Space plasmas, Shocks, Solar wind
JWST MIRI MRS Images of Disk Winds, Water, and CO in an Edge-on Protoplanetary Disk. We present JWST MIRI MRS observations of the edge-on protoplanetary disk around the young subsolar-mass star Tau 042021, acquired as part of the Cycle 1 GO program "Mapping Inclined Disk Astrochemical Signatures." These data resolve the mid-IR spatial distributions of H2, revealing X-shaped emission extending to ∼200 au above the disk midplane with a semiopening angle of 35° ± 5°. We do not velocity-resolve the gas in the spectral images, but the measured semiopening angle of the H2 is consistent with a magnetohydrodynamic wind origin. A collimated, bipolar jet is seen in forbidden emission lines from [Ne II], [Ne III], [Ni II], [Fe II], [Ar II], and [S III]. Extended H2O and CO emission lines are also detected, reaching diameters of ∼90 and 190 au, respectively. Hot molecular emission is not expected at such radii, and we interpret its extended spatial distribution as scattering of inner disk molecular emission by dust grains in the outer disk surface. H I recombination lines, characteristic of inner disk accretion shocks, are similarly extended and are likely also scattered light from the innermost star–disk interface. Finally, we detect extended polycyclic aromatic hydrocarbon (PAH) emission at 11.3 μm cospatial with the scattered-light continuum, making this the first low-mass T Tauri star around which extended PAHs have been confirmed, to our knowledge. MIRI MRS line images of edge-on disks provide an unprecedented window into the outflow, accretion, and scattering processes within protoplanetary disks, allowing us to constrain the disk lifetimes and accretion and mass-loss mechanisms.

Keywords: James Webb Space Telescope, Molecular spectroscopy, Protoplanetary disks, Planet formation
tdescore: An Accurate Photometric Classifier for Tidal Disruption Events. Optical surveys have become increasingly adept at identifying candidate tidal disruption events (TDEs) in large numbers, but classifying these generally requires extensive spectroscopic resources. Here we present tdescore, a simple binary photometric classifier that is trained using a systematic census of ∼3000 nuclear transients from the Zwicky Transient Facility (ZTF). The sample is highly imbalanced, with TDEs representing ∼2% of the total. tdescore is nonetheless able to reject non-TDEs with 99.6% accuracy, yielding a sample of probable TDEs with recall of 77.5% for a precision of 80.2%. tdescore is thus substantially better than any available TDE photometric classifier scheme in the literature, with performance not far from spectroscopy as a method for classifying ZTF nuclear transients, despite relying solely on ZTF data and multiwavelength catalog cross matching. In a novel extension, we use "Shapley additive explanations" to provide a human-readable justification for each individual tdescore classification, enabling users to understand and form opinions about the underlying classifier reasoning. tdescore can serve as a model for photometric identification of TDEs with time-domain surveys, such as the upcoming Rubin observatory.

Keywords: Sky surveys, Black holes, Tidal disruption, Galaxy nuclei, Time domain astronomy