Sazuna/UAT_keywords huggingface dataset:
Observing Supernova Neutrino Light Curves with Super-Kamiokande. V. Distance Estimation with Neutrinos. Neutrinos are pivotal signals in multimessenger observations of supernovae (SNe). Recent advancements in the analysis method of supernova (SN) neutrinos, especially in quantitative analysis, have significantly broadened scientific possibilities. This study demonstrates the feasibility of estimating distances to SNe using neutrinos. This estimation utilizes the direct relationship between the radius of a neutron star (NS) and the distance to the supernova, which is analogous to main-sequence fitting. The radius of an NS is determined with an approximate uncertainty of 10% through observations such as X-rays and gravitational waves. By integrating this information, the distance to the supernova can be estimated with an uncertainty of within 15% at a 95% confidence level. It has been established that neutrinos can pinpoint the direction of supernovae, and when combined with distance estimates, three-dimensional localization becomes achievable. This capability is vital for follow-up observations using multimessenger approaches. Moreover, more precise distance determinations to SNe through follow-up observations, such as optical observations, allow for accurate measurements of neutron-star radii. This data, via the neutron-star mass─radius relationship, could provide various insights into nuclear physics.

Keywords: High energy astrophysics, Neutron stars, Neutrino astronomy, Core-collapse supernovae
Star Formation in the Lopsided Galaxy Arp 291. We have investigated the star formation process taking place in the lopsided galaxy Arp 291, based on narrowband images in the Hα, [N II]λ6583, and [O III]λ5007 emission lines, obtained using the modern tunable photometer MaNGaL at the Caucasus Mountain Observatory. We have diagnosed 30 star-forming (SF) regions by means of the Baldwin–Phillips–Terlevich method. The oxygen abundance of the ionized gas in the SF regions varies in the range from 8.17 ± 0.04 to 8.47 ± 0.16 dex, which is typical for spiral and irregular galaxies, and shows an anticorrelation with the surface density of current star formation rates. Star formation in the lopsided galaxy Arp 291 occurs in separate clumps comparable in size to those observed in spiral and lenticular galaxies, at a rate typical for these types of galaxies. The clumps of current star formation are located irregularly in the distorted spiral arms of Arp 291. Possible causes of lopsidedness of the galaxy are discussed.

Keywords: Extragalactic astronomy, Star forming regions, Late-type galaxies, Star formation
Shaping Outflows and Jets by Ambient Pressure: A Unified Framework. Astrophysical outflows are ubiquitous across cosmic scales, from stellar to galactic systems. While diverse launching mechanisms have been proposed, we demonstrate that these outflows share a fundamental commonality: their morphology follows the physics of pressure-confined supersonic flows. By extending classical de Laval nozzle theory to account for ambient pressure gradients, we present a unified framework that successfully describes outflows from young stellar objects to active galactic nuclei. This simplified approach, compared to full magnetohydrodynamic treatments, captures the essential physics governing outflow shapes across different scales. Our model reveals a remarkable consistency of pressure profiles, characterized by a power-law exponent near "–2" across 6 orders of magnitude in spatial scale, independent of the internal characteristics of the outflow or the nature of the central engine. This discovery suggests a universal mechanism for outflow collimation and acceleration, bridging the gap between theoretical models and observational features across a wide range of astronomical scales.

Keywords: Radio active galactic nuclei, Young stellar objects, Bipolar nebulae, Radio jets
Solar Coronal Mass Ejection and Post–Coronal Mass Ejection Blob Formation in Two-fluid Simulations. A coronal mass ejection (CME) and post-CME blob phenomena in the solar atmosphere, associated with shear flow and convergent flow perturbations in the photosphere, are investigated using a resistive two-fluid (electron–ion) code. It is found that there are notable deviations between the two-fluid and previous magnetohydrodynamic simulations. In this two-fluid approach, the decoupling motions of ions and electrons leads to the emergence of an additional electric field. With expansion of a magnetic arcade associated with the footpoint shear flows, a thin current sheet is formed and a series of magnetic reconnections occurs in the lower region of the central magnetic arcade. The initial reconnection gives rise to a rising magnetic island, displaying typical CME characteristics. Subsequent reconnections produce smaller, more rapidly ascending blobs. These smaller blobs ultimately merge with the primary CME core, thereby accelerating its ascent.

Keywords: Solar corona, Solar coronal mass ejections, Solar magnetic reconnection
No Galaxy-scale [C II] Fast Outflow in the z = 6.72 Red Quasar HSC J1205–0000. HSC 120505.09-000027.9 (J1205–0000) is one of the highest redshift (z = 6.72) dust-reddened quasars (red quasars) known to date. We present an improved analysis of Atacama Large Millimeter/submillimeter Array data of the [C II] 158 μm line and the underlying rest-frame far-infrared (FIR) continuum emission, previously reported in T. Izumi et al. (2021b), toward J1205–0000. Red quasars are thought to be a transitional phase from an obscured starburst to a luminous blue quasar, in some cases associated with massive outflows driven by the active galactic nucleus (AGN). J1205–0000 has a high FIR luminosity, LFIR = 2.5 × 1012 L⊙ and a total IR luminosity of LTIR = 3.5 × 1012 L⊙, corresponding to a star formation rate of ∼528 M⊙ yr‑1. With the [C II]-based dynamical mass of ∼1 × 1011 M⊙, we conclude that J1205–0000 is hosted by a starburst galaxy. In contradiction to T. Izumi et al., our improved analysis shows no hint of a broad component in the [C II] line spectrum. Thus there is no evidence for a host galaxy-scale fast [C II] outflow, despite the fact that J1205–0000 has fast nuclear ionized outflows seen in the rest-frame UV. We explore several scenarios for this discrepancy (e.g., the early phase of AGN feedback, reliability of the [C II] line as a tracer of outflows), and we claim that it is still too early to conclude that there is no significant negative AGN feedback on star formation in this red quasar.

Keywords: AGN host galaxies, Galaxy formation, Quasars, Stellar jets, Active galaxies, Low-luminosity active galactic nuclei, Active galactic nuclei, Radio interferometry, High-redshift galaxies
Baryon Pasting the Uchuu Light-cone Simulation. We present the Baryon Pasted (BP) X-ray and thermal Sunyaev–Zel'dovich (tSZ) maps derived from the half-sky Uchuu light-cone simulation. These BP-Uchuu maps are constructed using more than 75 million dark matter halos with masses M500c ≥ 1013 M⊙ within the redshift range 0 ≤ z ≤ 2. A distinctive feature of our BP-Uchuu light-cone maps is their capability to assess the influence of both extrinsic and intrinsic scatter caused by triaxial gaseous halos and internal gas characteristics, respectively, at the map level. We show that triaxial gas drives substantial scatter in X-ray luminosities of clusters and groups, accounting for nearly half of the total scatter in core-excised measurements. Additionally, scatter in the thermal pressure and gas density profiles of halos enhances the X-ray and SZ power spectra, leading to biases in cosmological parameter estimates. These findings are statistically robust due to the extensive sky coverage and large halo sample in the BP-Uchuu maps. The BP-Uchuu maps are publicly available online via Globus (https://app.globus.org/file-manager?origin_id=cf8dadb7-b6e9-4e2c-abc1-0813877efc13).

Keywords: Galaxy clusters, Intracluster medium, N-body simulations, Large-scale structure of the universe
The Extreme-ultraviolet Precursors and Postcursors of Solar Flares. EUV brightenings are small-scale magnetic reconnection events that consistently appear before and after solar flares. However, it is not well understood how EUV precursors might foreshadow flares and what the physical connection is between the EUV signatures and flares. We studied flare-active and inactive periods in three separate studies using the Detection and EUV Flare Tracking (DEFT) tool. In Study 1, EUV signatures were identified in 200 no-flare days, in Study 2 EUV signatures before 360 flares were analyzed, and in Study 3 close to 36,000 EUV signatures were detected, and their pre- and postflare distribution and trends were studied. Our key questions were as follows: do EUV signatures occur consistently before flares, do EUV signatures occur without flares, are there flares without EUV precursors, and is it possible to forecast different magnitude flares based on preceding EUV signature trends? Study 1 showed that in no-flare periods EUV signatures were only detected 4% of the time. Study 2 showed that EUV precursors were present 92% of the time within 6 hr before ≥C-class flares. Study 3 showed that over 90% of the signatures were associated with flares (≥B class), and over 50% of all signatures were associated with ≥M-class flares. A superposed epoch analysis showed precursor frequency peaks at ∼70 and 100 minutes before M- and X-class flares, respectively, while B- and C-class flares had no notable precursor frequency peaks. These results demonstrate the close connection between EUV signatures and flares and the significant potential EUV signatures have in improving space weather forecasting.

Keywords: Solar flares, Solar extreme ultraviolet emission, Astronomy image processing
PSR J1947‑1120: A New Huntsman Millisecond Pulsar Binary. We present the discovery of PSR J1947–1120, a new huntsman millisecond pulsar with a red giant companion star in a 10.3 day orbit. This pulsar was found via optical, X-ray, and radio follow-up of the previously unassociated γ-ray source 4FGL J1947.6–1121. PSR J1947–1120 is the second confirmed pulsar in the huntsman class and establishes this as a bona fide subclass of millisecond pulsars. We use MESA models to show that huntsman pulsars can be naturally explained as neutron star binaries whose secondaries are currently in the "red bump" region of the red giant branch, temporarily underfilling their Roche lobes and hence halting mass transfer. Huntsman pulsars offer a new view of the formation of typical millisecond pulsars, allowing novel constraints on the efficiency of mass transfer and recycling at an intermediate stage in the process.

Keywords: Neutron stars
Tracing the Winds: A Uniform Interpretation of Helium Escape in Exoplanets from Archival Spectroscopic Observations. Over the past decade, observations of evaporating exoplanets have become increasingly common, driven by the discovery of the near-infrared helium-triplet line as a powerful probe of atmospheric escape. This process significantly influences the evolution of exoplanets, particularly those smaller than Jupiter. Both theoretical and observational studies have aimed to determine how efficiently exoplanets convert their host star's X-ray and ultraviolet (XUV) radiation into atmospheric mass loss. In this study, we employ the open-source atmospheric escape model p-winds to systematically analyze all publicly available helium triplet spectroscopic detections related to exoplanetary atmospheric escape. Our findings indicate that the retrieved outflows strongly depend on the ratio of XUV flux to planetary density (FXUV/ρp), supporting the theoretical framework of energy-limited mass loss. We constrain population-level photoevaporative efficiencies to 0.34 ± 0.13 and 0.75 ± 0.21 for hydrogen-helium fractions of 0.90 and 0.99, respectively. These results offer new insights into exoplanetary atmospheric evolution and will aid future studies on exoplanet population demographics.

Keywords: Infrared astronomy, Exoplanet evolution, Extrasolar gaseous planets, Exoplanet atmospheres
ALMA FACTS. II. Large Scale Variations in the <SUP>12</SUP>CO(J = 2 ─ 1) to <SUP>12</SUP>CO(J = 1 ─ 0) Line Ratio in Nearby Galaxies. We present 12CO(J = 1 ─ 0) mapping observations over ∼1/2 of the optical disk of 12 nearby galaxies from the Fundamental CO 1─0 Transition Survey of nearby galaxies (FACTS), using the ALMA Total Power array. Variations in the 12CO(J = 2 − 1)/12CO(J = 1 − 0) line ratio r21 are investigated. The luminosity-weighted r21 of the 11 sample galaxies ranges from 0.52 to 0.69 with an average of 0.61. We use position─velocity diagrams along the major axis and tilted ring models to separate the normal rotating galactic disk from kinematic outliers that deviate from pure circular rotation. We find that r21 is systematically higher in outliers compared to the disk. We compare r21 between SA, SAB, and SB galaxies, and find no significant difference in the average r21 depending on the presence of galactic bars. We find, however, that the radial gradient in r21 is bimodal, where a group containing all SA galaxies prefer constant or very shallow r21 gradients out to 40% of the optical radius, while another group containing all SB galaxies have a steep r21 gradient, decreasing by ∼20% before 40% of the optical radius, which also corresponds to the radius of the stellar bar. After this radius, these galaxies become consistent with a constant or shallow trend in r21. The large scale trend in r21 can have implications for how we interpret observations made solely in the 12CO(J = 2 − 1) line.

Keywords: Galaxy disks, Molecular gas, CO line emission
Spectral Variations across Latitudes on Asteroid (3200) Phaethon. 3200 Phaethon is a near-Earth asteroid known to be actively emitting dust and gas when near its perihelion, and it is the target of the Japanese DESTINY+ mission. Several visible–near-IR spectra were obtained of Phaethon during 2003–2017, which have been collected together and analyzed with respect to its shape model. Using a thermal model, we examine the diurnal temperature variations across Phaethon's surface (ΔT ∼ 600 K). We find different solar radiation heating between the north and south regions, with very high surface temperatures in the south region (max peak ∼ 1050 K), while a lower temperature is found in the north region (a mean value of 760 K). Our analysis of the photometrically corrected slope suggests a latitudinal trend in surface composition. We propose that the northern region of Phaethon may be linked to unusual chondrites and naturally heated Y-82162 samples (63–125 μm and/or chips), while the southern region shows similarities to Ivuna CI chondrites heated to 700°C (0–125 μm). The equatorial region appears to include a mixture of materials from both hemispheres.

Keywords: Small Solar System bodies, Meteorites, Asteroids, Spectroscopy
Predicting Solar Energetic Particle Events with Time Series Shapelets. Solar energetic particle (SEP) events pose significant risks to both space and ground-level infrastructure, as well as to human health in space. Understanding and predicting these events are critical for mitigating their potential impacts. In this paper, we address the challenge of predicting SEP events using proton flux data. We leverage some of the most recent advances in time series data mining, such as shapelets and the matrix profile, to propose a simple and easily understandable prediction approach. Our objective is to mitigate the interpretability challenges inherent to most machine learning models and to show that other methods exist that can not only yield accurate forecasts but also facilitate exploration and insight generation within the data domain. For this purpose, we construct a multivariate time series data set consisting of proton flux data recorded by the National Oceanic and Atmospheric Administration's geosynchronous orbit Earth-observing satellite. Then, we use our proposed approach to mine shapelets and make predictions using a random forest classifier. We demonstrate that our approach rivals state-of-the-art SEP prediction, offering superior interpretability and the ability to predict SEP events before their parent eruptive flares.

Keywords: Solar energetic particles, Space weather, Time series analysis
Discovery and Detailed Study of the M31 Classical Nova AT 2023tkw: Evidence for Internal Shocks. We present a detailed analysis of an extragalactic slow classical nova in M31 exhibiting multiple peaks in its light curve. Spectroscopic and photometric observations were used to investigate the underlying physical processes. Shock-induced heating events resulting in the expansion and contraction of the photosphere are likely responsible for the observed multiple peaks. Deviation of the observed spectrum at the peak from the models also suggests the presence of shocks. The successive peaks occurring at increasing intervals could be due to the series of internal shocks generated near or within the photosphere. Spectral modeling suggests a low-mass white dwarf (WD) accreting slowly from a companion star. The ejecta mass, estimated from spectral analysis, is ~10‑4 M⊙, which is typical for a slow nova. We estimate the binary, by comparing the archival Hubble Space Telescope data and eruption properties with stellar and nova models, to comprise a 0.65 M⊙ primary WD and a K III cool evolved secondary star.

Keywords: Photoionization, Light curve classification , Optical astronomy, Light curves, Radiative transfer, Photometry, Spectroscopy, Transient detection, Shocks, Cataclysmic variable stars, Andromeda Galaxy, Classical novae
Analytical and Numerical Methods for Circumbinary Disk Dynamics. II. Inclined Disks. To gain insight into the dynamical influence of a supermassive black hole binary on a circumbinary accretion disk, we investigate the binary and viscous torque densities throughout such a disk, with emphasis on the final density distribution, particularly the size and stability of the central gap between the binary and the inner edge of the disk. We limit ourselves to the simplified case of a massless viscous thin accretion disk under the influence of the gravitational potential from a binary system whose orbital plane is inclined relative to the disk. We employ two-dimensional Newtonian hydrodynamics simulations to examine the influence of two model parameters: the mass ratio of the binary and the inclination angle between the binary and the disk. We investigate their impact on the density and torque distribution. In our analytical approach, we consider the stability of epicycles induced by the perturbative effect of the asymmetric inclined binary gravitational potential on Keplerian circular orbits. Through our simulations, we observe that certain configurations never attain a quasi-steady state, where the density profile averaged over many orbits stabilizes. This instability occurs when the inclination is close to 45°. Furthermore, we identify configurations where there is never a persistent balance between the dynamical and viscous torque densities, as well as cases where the location of this balance oscillates or exhibits other time-dependent behavior over viscous timescales. These findings have implications for understanding both the expected gravitational-wave signal and electromagnetic counterparts from supermassive black hole binaries.

Keywords: Accretion, Circumstellar disks, Orbital resonances, Computational methods, Orbital theory, Astrophysical fluid dynamics, Astrophysical black holes
The Disk Wind Contribution to the Gamma-Ray Emission from the Nearby Seyfert Galaxy GRS 1734‑292. Radio-quiet Seyfert galaxies have been detected in GeV gamma rays by the Fermi Large Area Telescope (LAT), but the origin of much of this emission is unclear. We consider the nearby example GRS 1734‑292, which exhibits weak starburst and jet activities that are insufficient to explain the observed gamma-ray flux. With the first detailed multiwavelength study of this source, we demonstrate that an active galactic nucleus (AGN) disk wind can account for its gamma-ray emission. Using a lepto-hadronic emission model based on a shocked ambient medium and a shocked wind region created by an AGN accretion disk wind, we identify two viable scenarios that are consistent with the Fermi-LAT data and multiwavelength observations: a hadronic pp-dominated scenario and a leptonic external-Compton-dominated scenario. Both of these show that future observations with the Cherenkov Telescope Array and the Southern Wide-field Gamma-ray Observatory could detect TeV emission from a disk wind in GRS 1734‑292. Such a detection would substantially improve our understanding of cosmic-ray acceleration efficiency in AGN disk wind systems and would establish radio-quiet Seyfert galaxies as cosmic-ray accelerators capable of reaching ultrahigh energies.

Keywords: Seyfert galaxies, Active galactic nuclei, Gamma-rays, Cosmic rays
CH<SUB>3</SUB>OH Thermal Lines Traces 6.7 GHz CH<SUB>3</SUB>OH Maser Variation of High-mass Protostar G353.273+0.641. This study reports an analysis of the 6.7 GHz CH3OH maser in the high-mass protostar G353.273+0.641 (G353), utilizing data from the Tianma Radio Telescope. G353 is a possibly periodic variation in the flux density of the maser with a period of ∼330 days. Our analysis of Atacama Large Millimeter/submillimeter Array archival data identified 44 CH3OH transitions within the gas envelope surrounding the protostar. The CH3OH envelope exhibited non–local thermodynamic equilibrium (LTE) conditions during the increase phase of the flux density of the maser, then transitioning to LTE (T ∼ 380 K) during the decay phase of the maser. This phenomenon is likely attributed to the recurrent heating of the protostellar envelope through heat waves, which are generated by the periodic luminosity oscillations of the central high-mass protostar. The propagation velocity of the heat wave is gauged to be ∼0.02c. These results emphasize the significance of integrating the variations in 6.7 GHz CH3OH masers with their surrounding circumstellar environments to advance our comprehension of high-mass star formation mechanisms.

Keywords: Massive stars, Protostars, Circumstellar masers, Interstellar thermal emission
Uncovering the Hidden Physical Structures and Protostellar Activities in the Low-metallicity S284-RE Region: Results from ALMA and JWST. We present an observational study of the S284-RE region, a low-metallicity area associated with the extended S284 H II region. A thermally supercritical filament (mass ∼2402 M⊙ and length ∼8.5 pc) is investigated using the Herschel column density map. The Spitzer ratio 4.5 μm/3.6 μm map traces the H2 outflows in this filament, where previously reported young stellar objects (YSOs) are spatially distributed. Analysis of the YSO distribution has revealed three active star-forming clusters (YCl1, YCl2, and YCl3) within the filament. YCl3 seems to be the most evolved and YCl2 the youngest, while YCl1 displays signs of nonthermal fragmentation. The JWST (F470N+F444W)/F356W ratio map reveals at least seven bipolar H2 outflows, with four (olc1–olc4) in YCl1 and three (ol1–ol3) in YCl2. The driving sources of these outflows are identified based on outflow geometry, Atacama Large Millimeter/submillimeter Array (ALMA) continuum peaks, and YSO positions. Two ALMA continuum sources—#2 and #3—from the M–Reff plot are recognized as potential massive star formation candidates. ALMA continuum source #2 hosts at least three outflow-driving sources, whereas ALMA continuum source #3 contains two. The bipolar outflow olc1, driven by an embedded object within continuum source #2, is likely a massive protostar, as indicated by the Br-α and PAH emissions depicted in the JWST (F405N+F444W)/F356W ratio map. The presence of H2 knots in the outflows olc1 and ol1 suggests episodic accretion. Overall, the study investigates a massive protostar candidate, driving the ∼2.7 pc H2 outflow olc1 and undergoing episodic accretion.

Keywords: Interstellar filaments, Interstellar dust extinction, Young stellar objects, Star formation, Interstellar medium, H II regions