Sazuna/UAT_keywords huggingface dataset:
A z ≃ 0.4 Galaxy Reflecting the High-redshift Little Red Dots: An Extended Starburst with an Overmassive Black Hole. One of the most remarkable discoveries of JWST is a population of compact, red sources at z &gt; 4, commonly referred to as Little Red Dots (LRDs). Spectroscopic identifications reported that most LRDs are active galactic nuclei, which are preferentially found around z ∼ 6 and could imply a key phase in the formation and growth of black holes (BHs) in the early Universe. Photometric surveys at lower redshift have recently been carried out to trace their evolution across cosmic time, and a small number of LRD-like galaxies have been spectroscopically identified at both Cosmic Noon and in the local Universe. Here we report the discovery of one of the lowest-z LRD-like galaxies, J204837.26-002437.2 (hereafter J2048) at z = 0.4330, using new Gemini-N/GMOS integral field unit observations combined with archival multiband photometric spectral energy distribution data. The GMOS data reveal extended blue emission from starburst with a star formation rate of 400 M⊙ yr−1, together with an extended, highly fast ionized outflow. This is the first spectroscopic confirmation of extended host emission and outflow in an LRD-like galaxy, providing a unique laboratory for understanding the nature of their high-redshift counterparts. Moreover, J2048 would host an extremely overmassive BH with a BH-to-stellar mass ratio of ≃60%, with the BH mass and host stellar mass estimated to be 1010.2 and 1010.4M⊙, respectively. We discuss the origin and evolutionary fate of J2048, and the implications that such low-z analogs have for interpreting the properties of high-z LRDs.

Keywords: AGN host galaxies, Supermassive black holes, Active galactic nuclei, Galaxy evolution, Ultraluminous infrared galaxies
NEXUS: A Spectroscopic Census of Broad-line AGNs and Little Red Dots at 3 ≲ z ≲ 6. We present a spectroscopic sample of 24 broad-line AGNs (BLAGNs) at 3 ≲ z ≲ 6 selected using F322W2+F444W NIRCam/WFSS grism spectroscopy of the central 100 arcmin2 area of the NEXUS survey. Among these BLAGNs, 15 are classified as Little Red Dots (LRDs) based on their rest-frame UV─optical spectral slopes and compact morphology. The number density of LRDs is ∼10−5 cMpc−3, with a hint of declining towards lower redshift. These BLAGNs span broad Hα luminosities of ∼1042.2─1043.5 erg s−1, black hole masses of ∼106.3─108.4 M⊙, and Eddington ratios of ∼0.1─1, though the estimates of black hole mass and Eddington ratio carry large systematic uncertainties. Half of the LRDs show strong Balmer absorption, suggesting high-density gas surrounding the line-emitting region. We detect extended (hundreds of parsecs) rest-frame UV─optical emission from the host galaxy in the majority of these LRDs, which contributes significantly or even dominantly to their total UV emission and largely accounts for the peculiar UV upturn of their spectral energy distribution. We also measure the small-scale (≲1 cMpc) clustering of these BLAGNs and LRDs by cross-correlating with a photometric galaxy sample. Extrapolating the power-law two-point correlation function model to large linear scales, we infer a linear bias of  3.69−2.21+2.78  and typical halo masses of a few ×1011h−1 M⊙ for BLAGNs at the sample median redshift of z ∼ 4.5. However, the inferred linear bias and halo masses of LRDs, while formally consistent with those for BLAGNs at ∼1.5σ, appear too large to be compatible with their space density, suggesting LRDs may have strong excess clustering on small scales.

Keywords: Supermassive black holes, Active galactic nuclei, High-redshift galaxies, Clustering
Constraining Properties of Dust Formed in Wolf─Rayet Binary WR 112 Using Mid-infrared and Millimeter Observations. Binaries that host a carbon-rich Wolf─Rayet (WC) star and an OB-type companion can be copious dust producers. Yet the properties of dust, particularly the grain size distribution, in these systems remain uncertain. We present Band 6 observations of WR 112 by the Atacama Large Millimeter/submillimeter Array telescope (ALMA), which are the first millimeter observations of a WC binary system capable of resolving its dust emission. By combining ALMA observations with James Webb Space Telescope images, we were able to analyze the spatially resolved spectral energy distribution (SED) of WR 112. We found that the SEDs are consistent with emissions from hydrogen-poor amorphous carbon grains. Notably, our results also suggest that the majority of grains in the system have radii below one micrometer, and the extended dust structures are dominated by nanometer-sized grains. Among four parameterizations of the grain radius distribution that we tested, a bimodal distribution, with abundant nanometer-sized grains and a secondary population of 0.1 μm grains, best reproduces the observed SED. This bimodal distribution helps to reconcile the previously conflicting grain size estimates reported for WR 112 and for other WC systems. We hypothesize that dust destruction mechanisms such as radiative torque disruption and radiative-driven sublimation are responsible for driving the system to the bimodal grain size distribution.

Keywords: WC stars, Binary stars, Stellar winds, Dust continuum emission, Wolf-Rayet stars, Circumstellar dust
The Perpendicularity of Dust Lanes and Radio Jets in Early-type Galaxies: Implications for Active Galactic Nuclei Feedback. The orientation of radio jets relative to their host galaxies offers an interesting avenue for probing the connection between active galactic nuclei (AGN) and their surroundings. Several studies have also investigated the orientation of nuclear dust features. We follow up on this previous work with newer Hubble Space Telescope imaging of early-type radio galaxies, and a largely automated process for measuring position angles. We classify the dust features as lanes, disks, or rings. Lanes are irregular structures that likely form from gas-rich minor mergers, while disks and rings are more well-defined and may form from settling lanes or internal mechanisms. We find that dust lanes do not have a preferred alignment relative to their host galaxies, but are preferentially perpendicular to the jets. In contrast, dust disks and rings tend to be closely aligned with the major axes of their host galaxies, but have varying orientations relative to the jets. Our results suggest that infalling dusty material from mergers can influence the angle of the radio jet. This would allow the jet orientation to change over time, and may help explain the role of AGN feedback in maintaining quiescence in massive galaxies.

Keywords: Radio jets, Hubble Space Telescope, Astrophysical dust processes, Active galactic nuclei, Galaxy quenching, Early-type galaxies
Ubiquitous High-frequency Waves and Disturbances in the Active Region Corona Observed with Cryo-NIRSP. The plasma of the solar corona harbors a multitude of coronal wave modes, some of which could be dissipated to provide the required energy and momentum to heat the corona and accelerate the solar wind. We present observations of the corona acquired with the newly commissioned infrared slit spectropolarimeter Cryo-NIRSP at the Daniel K. Inouye Solar Telescope (DKIST), Haleakalā, Hawaii to study the high-frequency wave behavior in closed, active region structures. Cryo-NIRSP observes the corona off the limb in the Fe XIII 1074 and 1079 nm forbidden atomic lines. The large aperture of DKIST allows us to explore the active region corona with a temporal resolution faster than a second with an achieved spatial resolution of 2″─5″. Enhanced wave power is observed in the coronal power spectra up to 100 mHz. We report evidence for spectroscopic detection of magnetohydrodynamic (MHD) wave modes with periodicities between 30 and 100 s in the observed active region corona and report their changing properties with height. Furthermore, we report on a statistically significant anticorrelation between the Fe XIII 1074 nm peak line intensity and line width. These observations show how the powerful spectropolarimetric capabilities of DKIST offer great promise for furthering our knowledge of coronal MHD waves.

Keywords: Active solar corona, Solar coronal waves, Infrared spectroscopy
Anomalous Narrow Line Seyfert I Galaxies from SDSS DR17. We present an analysis of 22,656 narrow-line Seyfert 1 galaxies (NLSy1s) from the Sloan Digital Sky Survey (SDSS) DR17 (0.1 ≤ z ≤ 0.9), identifying a sample of spectroscopically anomalous sources. These anomalies were detected via the Spectroscopic Quasar Anomaly Detection (SQuAD) algorithm, which employed principal component analysis and hierarchical k-means clustering. Various physical diagnostic analyses were performed such as color excess (E(B − V)) calculations, Wide-field Infrared Survey Explorer color analysis, probing [O III] equivalent width as an inclination indicator, the Baldwin─Phillips─Terlevich (BPT) diagram, and eigenvector 1 diagram. We detected 620 anomalous NLSy1s classified into two groups. The first is 246 red NLSy1s, exhibiting host-galaxy-dominated spectra with a low-luminosity active galactic nucleus (AGN) core revealed by the emission line widths. The other set consists of 374 blue NLSy1s, which are highly luminous galaxies with enhanced AGN activity, bluer continua as compared to a typical NLSy1, and have stronger Fe II emission. Finally, we identify a third group of 257 outliers, identified as intermediate Seyferts, which are a class of Seyfert galaxies identified by composite emission profiles and extremely strong emission lines paired with virtually no continuum. These sources also exhibit rare and high ionization emission lines unseen in any other NLSy1 spectra (e.g., [Ne v] λ3345, Ne v λ3426, Ne III λ3869, etc.). We conclude that the differentiating factor between red and blue NLSy1s is not dust obscuration or orientation effects, but intrinsic distinction in AGN activity. The resulting sample is presented as a value-added catalog.

Keywords: AGN host galaxies, Supermassive black holes, Quasars, Active galaxies, Seyfert galaxies, Active galactic nuclei, Galaxy spectroscopy, Catalogs
Atmospheric Circulation of High-obliquity Mini-Neptunes. With the operation of JWST, atmospheric characterization has now extended to low-mass exoplanets. In compact multiplanetary systems, secular spin-orbital resonance may preserve high obliquities and asynchronous rotation even for tidally despinning, low-mass planets, potentially leading to unique atmospheric circulation patterns. To understand the impact on the atmospheric circulation and to identify the potential atmospheric observational signatures of such high-obliquity planets, we simulate the three-dimensional circulation of a representative mini-Neptune K2-290 b, whose obliquity may reach about 67°. Whether synchronously rotating or not, the planet's slow rotation, moderate temperature, and radius result in a global weak temperature gradient (WTG) behavior with moderate horizontal temperature contrasts. Under synchronous rotation, broad eastward superrotating jets efficiently redistribute heat. Circulation in an asynchronous rotation exhibits a seasonal cycle driven by high obliquity, along with quasiperiodic oscillations in winds and temperatures with a period of ∼70 orbital periods. These oscillations, driven by wave─mean flow interactions, extend from low- to midlatitudes due to the slow planetary rotation. Higher atmospheric metallicity strengthens radiative forcing, increasing temperature contrasts and jet speeds. Clouds have minimal impact under synchronous rotation but weaken jets under nonsynchronous rotation by reducing temperature contrasts. In all cases, both thermal emission and transmission spectra exhibit moderate observational signals at a level of 100 ppm, and high-obliquity effects contribute differences at the ∼10 ppm level. Our results are also applicable to a range of potential high-obliquity exoplanets, which reside in the WTG regime and likely exhibit nearly homogeneous horizontal temperature patterns.

Keywords: Exoplanet atmospheric dynamics, Exoplanet atmospheric variability, Planetary climates, Exoplanet atmospheres
Instabilities, Wave Emission, and Energy Transport along Bursty Bulk Flows and Supra-arcade Downflows: Differences, Similarities, and Effects on the Surrounding Regions. We examine the stability conditions for two posteruptive phenomena in the solar─terrestrial environment, namely, bursty bulk flows (BBFs) in the Earth's magnetotail and supra-arcade downflows (SADs) in the solar corona. We investigate the possibility of Kelvin─Helmholtz instability (KHI) and magnetohydrodynamic (MHD) wave emission along these two shear flow regions that have striking similarities. Our results suggest that the KHI and emission of propagating MHD waves due to KHI are possible along both SADs and BBFs with varying strengths depending on the background plasma parameters. These waves offer a means of energy transport out of SADs and BBFs. In the case of SADs, KHI-emitted MHD waves may transport energy into the surrounding regions and contribute to solar coronal heating. In the case of BBFs, KHI waves may influence the magnetosphere─ionosphere coupling in the near-Earth magnetotail regions by enhancing particle injections, auroral brightenings, and field-aligned currents. Moreover, the reduction of the kinetic energy of the flows arising from the emission of MHD waves may contribute to the braking of both SADs and BBFs.

Keywords: Space plasmas, Plasma jets, Solar coronal heating, Solar coronal waves, Solar-terrestrial interactions, Planetary magnetospheres, Magnetohydrodynamical simulations
The Role of Gas Stripping in the Quenching of Satellite Galaxies Using SHARK v2.0. Observational studies have made substantial progress in characterizing quenching as a function of galaxy stellar mass and environment, but they are often limited in their ability to constrain quenching timescales and to determine the dominant environmental process responsible for the shutting down of star formation. To address this, we combine recent Sloan Digital Sky Survey (SDSS) observations with the SHARK v2.0 semi-analytic model to study the quenching of satellite galaxies in groups and clusters. We generate mock SDSS-like observations to calibrate the hot halo and cold interstellar medium gas stripping prescriptions against observed satellite quenched fractions, finding that the previously adopted stripping prescriptions in SHARK v2.0 are too aggressive and overestimate the quenched fraction of satellite galaxies. Reducing the efficiency of both hot and cold gas stripping yields excellent agreement with observations for low- and intermediate-mass satellite galaxies. We use the calibrated model to investigate quenching timescales and find that satellites quench more quickly in clusters compared to groups, with timescales that generally decrease with increasing stellar mass. The long (&gt;2 Gyr) timescales we measure favour hot halo gas removal as the dominant driver of satellite quenching.

Keywords: Galaxy clusters, Galaxy evolution, Galaxies, Astronomical simulations
CW Cas: A Solar-type Contact Binary System with an Unseen Third Companion in a Hierarchical Quadruple System. We present a comprehensive multiband photometric and spectroscopic study of the G-type binary CW Cas. Analysis of its double-lined spectroscopic radial velocity curves yields a reliable mass ratio of q = 1.88(9). By combining modeling of the radial velocity curves with BVRcIc and TESS light curves, we found that CW Cas is a W-subtype shallow contact binary with a fill-out factor of 15%. The components have masses of 0.98(6) M⊙ and 0.52(4) M⊙, separated by 2.25(5) R⊙. A notable asymmetry in the maxima of the light curves was detected and explained by a dark spot located on the surface of at least one component. Comparison of light curves from different years revealed that these dark spot activities exhibit cyclic variations with an approximate period of 349 days. Orbital period analysis via its O − C diagram spanning 125 yr shows a long-term decrease superimposed with a periodic oscillation caused by the light-travel time effect due to a third body. This tertiary component has an orbital period of P3 = 99.4(6) yr and a minimal mass of M3 = 0.91(1) M⊙. The absence of detectable signatures for this massive object in either the spectroscopic or photometric datasets implies it should be a compact object. Furthermore, a visual companion was identified based on Gaia Data Release 3 astrometric data, suggesting that CW Cas is part of a hierarchical quadruple system. As such, CW Cas represents a valuable laboratory for probing a 2 + 1 + 1 hierarchical multiple system hosting a compact object.

Keywords: Close binary stars, Eclipsing binary stars, Binary stars, Wide binary stars
The Cosmic Owl: Twin Active Collisional Ring Galaxies with Starburst Merging Front at z = 1.14. Galaxy mergers play a critical role in driving galaxy evolution, especially by transforming galaxy morphology, redistributing gas around galaxies, triggering active galactic nuclei (AGN), and stimulating star formation. We present the Cosmic Owl, a galaxy merger at z = 1.14, identified in the COSMOS field. Deep imaging and spectroscopy from JWST, the Atacama Large Millimeter/submillimeter Array, and the Very Large Array reveal a complex system of twin collisional ring galaxies, exhibiting nearly identical morphologies. The grism spectra from the JWST COSMOS-3D program confirm that both galaxies host an AGN. A bipolar radio jet from one AGN extends to strike the merging front. In addition, we detect a starburst at the merging front, characterized by luminous extended nebular line emission and a massive cold gas reservoir. This starburst is likely triggered by interstellar shocks induced by galaxy collision and the AGN jet. The twin ring structure of the Cosmic Owl requires further numerical simulations to clarify the precise conditions that lead to the formation of this rare morphology. This system exemplifies how shock-induced star formation, driven by galaxy collision or AGN jet, can act as a crucial mechanism for triggering intense starbursts in the early Universe.

Keywords: Starburst galaxies, Jets, Interacting galaxies, Interstellar medium
The ASTRID Simulation at z = 0: From Massive Black Holes to Large-scale Structure. We present the z = 0 results for the cosmological simulation ASTRID. Hosting 2 × 55003 ≍ 0.33 trillion particles in a box of 370 Mpc per side, ASTRID is one of the largest cosmological hydrodynamic simulations evolved to z = 0. ASTRID features a large population of massive black holes (MBHs), covering a wide mass range 4 × 104 ∼ 2 × 1011 M⊙. The adopted dynamical friction model provides a relatively accurate description of MBH dynamics, making ASTRID a powerful tool to study MBH growth and mergers in a cosmological context. ASTRID successfully captures the coevolution of MBHs and their host galaxies, producing MBH─M⋆ and MBH─σ relations in good agreement with observations. Notably, ASTRID generates scatter in these relations that is more consistent with observations than previous simulations, indicating a more realistic MBH diversity. The galaxy stellar mass function at z = 0 is generally consistent with observational constraints. When dust attenuation is applied, the galaxy luminosity function also agrees well with observations, and the bimodality in galaxy colors is reproduced as well. ASTRID hosts a large population of massive galaxy groups and clusters: seven halos have M200c &gt; 1015 M⊙, and 9709 halos have M200c &gt; 1013 M⊙. We quantify the stellar mass content in these halos, and find that the correlations between the stellar and halo mass match well with observational constraints. Finally, we present the z = 0 power spectra of MBH and galaxies, as well as their bias with respect to the matter power spectrum. We find that MBHs with MBH ≥ 108 M⊙ and galaxies with M⋆ ≥ 1010.5 M⊙ serve as good tracers of large-scale structure.

Keywords: Hydrodynamical simulations, Supermassive black holes
Investigation of the Quasi-periodic Oscillation Phase Lag of RE J1034+396. We conduct an in-depth study of the quasi-periodic oscillation (QPO) properties of RE J1034+396 by constructing QPO phase-folded light curves from 10 XMM-Newton observations during 2020─2021. Our analysis reveals that the QPO in the source exhibits two mutually convertible lag-energy modes: "hard lag" and "soft lag." Despite different lag characteristics, the energy dependencies of the rms amplitude of the QPO under both modes are consistent, suggesting the two types of QPO originate from the same physical mechanism. By performing a spectral analysis, we further find a correlation between time-lag modes and spectral states: the soft lag mode typically corresponds to harder X-ray spectra and higher blackbody temperatures. Through comprehensive comparison of multiple theoretical models, we propose that the relativistic precession model of the corona provides a plausible qualitative explanation for the observed complex phenomena, including time-lag mode transitions, and variations of spectral hardness and QPO signal strength.

Keywords: Accretion, Active galactic nuclei, X-ray active galactic nuclei
An Investigation of 5 yr Simultaneous X-Ray and Radio Light Curves of the Dwarf Seyfert Galaxy UGC 6728. We present serendipitous simultaneous radio and X-ray light curves of the dwarf Seyfert galaxy UGC 6728 spanning 5 yr. The X-ray light curve exhibits a flaring period, followed by a gradual rise and decline. Throughout these events, the X-ray hardness ratio and spectrum do not change significantly. The radio flux is constant, as far as can be determined from its sparse sampling, until the end of the X-ray flare, then decreases by a factor of two by the midpoint of the gradual X-ray rise before returning to baseline at the end of the X-ray decline. We interpret this behavior in light of a similar event recently reported in NGC 2992, in which there is a temporary obscuration of the radio source by a blob of plasma ejected by a magnetic reconnection in the accretion disk. The energetics of the X-ray flare are consistent with those expected from magnetic disk activity. As in NGC 2992, the X-ray spectrum does not evolve during the obscuration event. We also discuss the possibility that the observed phenomena are due to normal active galactic nuclei coronal flaring and variability, which is plausible but unlikely, given the lack of spectral variation.

Keywords: Radio cores, Active galactic nuclei, X-ray active galactic nuclei
Saturation of the Large-scale Magnetic Field for Fast Rotating Solar-like Stars Driven by Inefficient Turbulent Angular Momentum Transport. Magnetic activity in solar-like stars shows a systematic dependence on stellar rotation rate, known as the "activity─rotation relationship." Recent observations further reveal that large-scale surface magnetic fields in solar-like stars are anticorrelated with the Rossby number (Ro) in the moderate regime (0.1 &lt; Ro &lt; 1), reaching saturation at extremely low Rossby numbers (Ro &lt; 0.1). The cause of this saturation remains one of the open issues in stellar dynamo theory. We performed nonlinear mean-field dynamo simulations with the stellar rotation rate and turbulent diffusivity (ν0) as free parameters. The dependence of the magnetic field strength (B) in the deep convection zone is quantified as ( B∝Ro−0.45ν00.54 ). Our analysis of the differential rotation energy shows that this dependence is maintained by a balance between the angular momentum transport by the turbulence and the large-scale magnetic field. Together with the reduction of the convective velocity revealed at extremely low Rossby numbers by recent local three-dimensional simulations, our results suggest that inefficient turbulent angular momentum transport might drive the saturation of the large-scale magnetic field.

Keywords: Magnetohydrodynamics, Stellar magnetic fields, Solar dynamo, Solar magnetic fields, Stellar rotation