adsabs/SciX_UAT_keywords huggingface dataset:
Deviations from the Infrared-radio Correlation in Massive, Ultracompact Starburst Galaxies

Feedback through energetic outflows has emerged as a key physical process responsible for transforming star-forming galaxies into the quiescent systems observed in the local universe. To explore this process, this paper focuses on a sample of massive and compact merger remnant galaxies hosting high-velocity gaseous outflows ( $| v| \gtrsim {10}^{3}$ km s-1), found at intermediate redshift (z ∼ 0.6). From their mid-infrared emission and compact morphologies, these galaxies are estimated to have exceptionally large star formation rate (SFR) surface densities (ΣSFR ∼ 103 M⊙ yr-1 kpc-2), approaching the Eddington limit for radiation pressure on dust grains. This suggests that star formation feedback may be driving the observed outflows. However, these SFR estimates suffer from significant uncertainties. We therefore sought an independent tracer of star formation to probe the compact starburst activity in these systems. In this paper, we present SFR estimates calculated using 1.5 GHz continuum Jansky Very Large Array observations for 19 of these galaxies. We also present updated infrared (IR) SFRs calculated from WISE survey data. We estimate SFRs from the IR to be larger than those from the radio for 16 out of 19 galaxies by a median factor of 2.5. We find that this deviation is maximized for the most compact galaxies hosting the youngest stellar populations, suggesting that compact starbursts deviate from the IR-radio correlation. We suggest that this deviation stems either from free-free absorption of synchrotron emission, a difference in the timescale over which each indicator traces star formation, or exceptionally hot IR-emitting dust in these ultra-dense galaxies.

Keywords: galaxy evolution; stellar feedback; star formation; starburst galaxies; galaxy mergers; radio astronomy; radio continuum emission; compact galaxies; e+a galaxies; luminous infrared galaxies
Early Results from GLASS-JWST. IX. First Spectroscopic Confirmation of Low-mass Quiescent Galaxies at z > 2 with NIRISS

How passive galaxies form, and the physical mechanisms which prevent star formation over long timescales, are some of the most outstanding questions in understanding galaxy evolution. The properties of quiescent galaxies over cosmic time provide crucial information to identify the quenching mechanisms. Passive galaxies have been confirmed and studied out to z ~ 4, but all of these studies have been limited to massive systems (mostly with $\mathrm{log}({M}_{\mathrm{star}}/{M}_{\odot })\gt 10.8$ ). Using JWST-NIRISS grism slitless spectroscopic data from the GLASS-JWST Early Release Science program, we present spectroscopic confirmation of two quiescent galaxies at ${z}_{\mathrm{spec}}={2.650}_{-0.006}^{+0.004}$ and ${z}_{\mathrm{spec}}={2.433}_{-0.016}^{+0.032}$ (3σ errors) with stellar masses of $\mathrm{log}({M}_{\mathrm{star}}/{M}_{\odot })={10.59}_{-0.05}^{+0.11}$ and $\mathrm{log}({M}_{\mathrm{star}}/{M}_{\odot })={10.07}_{-0.03}^{+0.06}$ (corrected for magnification factors of μ = 2.0 and μ = 2.1, respectively). The latter represents the first spectroscopic confirmation of the existence of low-mass quiescent galaxies at cosmic noon, showcasing the power of JWST to identify and characterize this enigmatic population.

Keywords: galaxies; high-redshift galaxies; quenched galaxies
Secondary Outflow Driven by the Protostar Ser-emb 15 in Serpens

We present the detection of a secondary outflow associated with a Class I source, Ser-emb 15, in the Serpens Molecular Cloud. We reveal two pairs of molecular outflows consisting of three lobes, that is, primary and secondary outflows, using Atacama Large Millimeter/submillimeter Array 12CO and SiO line observations at a resolution of ~318 au. The secondary outflow is elongated approximately perpendicular to the axis of the primary outflow in the plane of the sky. We also identify two compact structures, Sources A and B, within an extended structure associated with Ser-emb 15 in the 1.3 mm continuum emission at a resolution of ~40 au. The projected sizes of Sources A and B are 137 au and 60 au, respectively. Assuming a dust temperature of 20 K, we estimate the dust mass to be 2.4 × 10-3 M ⊙ for Source A and 3.3 × 10-4 M ⊙ for Source B. C18O line data imply rotational motion around the extended structure, but we cannot resolve rotational motion in Source A and/or B because the angular and frequency resolutions are insufficient. Therefore, we cannot conclude whether Ser-emb 15 is a single or binary system. Thus, either Source A or Source B could drive the secondary outflow. We discuss two scenarios that might explain the driving mechanism of the primary and secondary outflows: the Ser-emb 15 system is (1) a binary system composed of Sources A and B, or (2) a single-star system composed of Source A alone. In either case, the system could be a suitable target for investigating the disk and/or binary formation processes in complicated environments. Detecting these outflows should contribute to understanding complex star-forming environments, which may be common in the star formation processes.

Keywords: protostars; low mass stars; star formation; star forming regions; circumstellar envelopes; common envelope binary stars; protoplanetary disks; co line emission; radio astronomy; radio continuum emission; jets; millimeter astronomy
Model-independent Distance Calibration and Curvature Measurement Using Quasars and Cosmic Chronometers

We present a new model-independent method to determine spatial curvature and to mitigate the circularity problem affecting the use of quasars as distance indicators. Cosmic-chronometer measurements are used to construct the curvature-dependent luminosity distance ${D}_{L}^{\mathrm{cal}}({{\rm{\Omega }}}_{K},z)$ using a polynomial fit. Based on the reconstructed ${D}_{L}^{\mathrm{cal}}({{\rm{\Omega }}}_{K},z)$ and the known ultraviolet versus X-ray luminosity correlation of quasars, we simultaneously place limits on the curvature parameter ΩK and the parameters characterizing the luminosity correlation function. This model-independent analysis suggests that a mildly closed universe ( ${{\rm{\Omega }}}_{K}=-0.918\pm 0.429$ ) is preferred at the 2.1σ level. With the calibrated luminosity correlation, we build a new data set consisting of 1598 quasar distance moduli, and use these calibrated measurements to test and compare the standard ΛCDM model and the Rh = ct universe. Both models account for the data very well, though the optimized flat ΛCDM model has one more free parameter than Rh = ct, and is penalized more heavily by the Bayes Information Criterion. We find that Rh = ct is slightly favored over ΛCDM with a likelihood of ∼57.7% versus 42.3%.

Keywords: quasars; cosmological parameters; cosmological models; distance indicators; observational cosmology
A New Stellar Companion to GJ 835

We present the discovery of a new stellar companion to GJ 835, detected using the Differential Speckle Survey Instrument on the 4.3 m Lowell Discovery Telescope and the Astrophysical Research Consortium 3.5 m telescope at Apache Point Observatory. This new companion joins a known companion in the system, making the system triple. Using 2MASS and Gaia data, as well as our observed properties, we estimate projected separations and spectral types for the three components in the system.

Keywords: m dwarf stars; low mass stars; high angular resolution; solar neighborhood
Is It Possible to Detect Coronal Mass Ejections on Solar-type Stars through Extreme-ultraviolet Spectral Observations?

Stellar coronal mass ejections (CMEs) from host stars are an important factor that affects the habitability of exoplanets. Although their solar counterparts have been well observed for decades, it is still very difficult to find solid evidence of stellar CMEs. Using the spectral line profile asymmetry caused by the Doppler shift of erupting plasma, several stellar CME candidates have been identified from spectral lines formed at chromospheric or transition region temperatures of the stars. However, a successful detection of stellar CME signals based on the profile asymmetries of coronal lines is still lacking. It is unclear whether we can detect such signals. Here we construct an analytical model for CMEs on solar-type stars and derive an expression of stellar extreme-ultraviolet (EUV) line profiles during CME eruptions. For different instrumental parameters, exposure times, CME propagation directions, and stellar activity levels, we synthesized the corresponding line profiles of Fe IX λ171.07 and Fe XV λ284.16. Further investigations provide constraints on the instrumental requirements for successful detection and characterization of stellar CMEs. Our results show that it is possible to detect stellar CME signals and infer their velocities based on spectral profile asymmetries using an EUV spectrometer with a moderate spectral resolution and signal-to-noise ratio. Our work provides important references for the design of future EUV spectrometers for stellar CME detection and the development of observation strategies.

Keywords: stellar coronal mass ejections; spectroscopy; stellar coronae; g dwarf stars
Simulations of Prominence Eruption Preceded by Large-amplitude Longitudinal Oscillations and Draining

We present magnetohydrodynamic (MHD) simulations of the evolution from quasi-equilibrium to eruption of a prominence-forming twisted coronal flux rope under a coronal streamer. We have compared the cases with and without the formation of prominence condensations, as well as the case where prominence condensations form but we artificially initiate the draining of the prominence. We find that the prominence weight has a significant effect on the stability of the flux rope and can significantly increase the loss-of-equilibrium height. The flux rope can be made to erupt earlier by initiating draining of the prominence mass. We have also performed a simulation where large-amplitude longitudinal oscillations of the prominence are excited during the quasi-static phase. We find that the gravity force along the magnetic field lines is the major restoring force for the oscillations, in accordance with the "pendulum model," although the oscillation periods are higher (by about 10%-40%) than estimated from the model because of the dynamic deformation of the field line dips during the oscillations. The oscillation period is also found to be slightly smaller for the lower part of the prominence in the deeper dips compared to the upper part in the shallower dips. The oscillations are quickly damped out after about two to three periods and are followed by prominence draining and the eventual eruption of the prominence. However, we do not find a significant enhancement of the prominence draining and earlier onset of eruption with the excitation of the prominence oscillations compared to the case without.

Keywords: magnetohydrodynamics; magnetohydrodynamical simulations; solar coronal mass ejections; solar prominences; solar filament eruptions
SDSS-IV MaNGA: A Star Formation-Baryonic Mass Relation at Kiloparsec Scales

Star formation rate density, ΣSFR, has shown a remarkable correlation with both components of the baryonic mass kiloparsec scales (i.e., the stellar mass density and molecular gas mass density, Σ* and Σmol, respectively) for galaxies in the nearby universe. In this study, we propose an empirical relation between ΣSFR and the baryonic mass surface density (Σb = Σmol,Av + Σ*, where Σmol,Av is the molecular gas derived from the optical extinction, AV) at kiloparsec scales using the spatially resolved properties of the MaNGA survey, the largest sample of galaxies observed via integral field spectroscopy (∼8400 objects). We find that ΣSFR tightly correlates with Σb. Furthermore, we derive an empirical relation between ΣSFR and a second-degree polynomial of Σb, yielding a one-to-one relation between these two observables. Both Σb and its polynomial form show a stronger correlation and smaller scatter with respect to ΣSFR than the relations derived using the individual components of Σb. Our results suggest that these three parameters are indeed physically correlated, suggesting a scenario in which the two components of the baryonic mass regulate the star formation activity at kiloparsec scales.

Keywords: disk galaxies; spiral galaxies; surveys; scaling relations
Tidal Disruptions of Main-sequence Stars. I. Observable Quantities and Their Dependence on Stellar and Black Hole Mass

This paper introduces a series of papers presenting a quantitative theory for the tidal disruption of main-sequence stars by supermassive black holes. Using fully general relativistic hydrodynamics simulations and MESA-model initial conditions, we explore the pericenter-dependence of tidal disruption properties for eight stellar masses ( $0.15\leqslant {M}_{\star }/{M}_{\odot }\leqslant 10$ ) and six black hole masses ( ${10}^{5}\leqslant {M}_{\mathrm{BH}}/{M}_{\odot }\leqslant 5\times {10}^{7}$ ). We present here the results most relevant to observations. The effects of internal stellar structure and relativity decouple for both the disruption cross section and the characteristic energy width of the debris. Moreover, the full disruption cross section is almost independent of M⋆ for M⋆/M⊙ ≲ 3. Independent of M⋆, relativistic effects increase the critical pericenter distance for full disruption events by up to a factor of ∼3 relative to the Newtonian prediction. The probability of a direct capture is also independent of M⋆; at MBH/M⊙ ≃ 5 × 106 this probability is equal to the probability of a complete disruption. The breadth of the debris energy distribution ΔE can differ from the standard estimate by factors of 0.35 - 2, depending on M⋆ and MBH, implying a corresponding change (∝(ΔE)-3/2) in the characteristic mass-return timescale. We provide analytic forms, suitable for use in both event rate estimates and parameter inference, to describe all these trends. For partial disruptions, we find a nearly universal relation between the star's angular momentum and the fraction of M⋆ remaining. Within the "empty loss-cone" regime, partial disruptions must precede full disruptions. These partial disruptions can drastically affect the rate and appearance of subsequent total disruptions.

Keywords: black hole physics; gravitation; general relativity; hydrodynamics; galaxy nuclei; stellar dynamics; supermassive black holes
A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): JWST Reveals a Filamentary Structure around a z = 6.61 Quasar

We present the first results from the JWST program A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE). This program represents an imaging and spectroscopic survey of 25 reionization-era quasars and their environments by utilizing the unprecedented capabilities of NIRCam Wide Field Slitless Spectroscopy (WFSS) mode. ASPIRE will deliver the largest ( $\sim 280\,{\mathrm{arcmin}}^{2}$ ) galaxy redshift survey at 3-4 μm among JWST Cycle 1 programs and provide extensive legacy values for studying the formation of the earliest supermassive black holes, the assembly of galaxies, early metal enrichment, and cosmic reionization. In this first ASPIRE paper, we report the discovery of a filamentary structure traced by the luminous quasar J0305-3150 and 10 [O III] emitters at z = 6.6. This structure has a 3D galaxy overdensity of δ gal = 12.6 over 637 cMpc3, one of the most overdense structures known in the early universe, and could eventually evolve into a massive galaxy cluster. Together with existing VLT/MUSE and ALMA observations of this field, our JWST observations reveal that J0305-3150 traces a complex environment where both UV-bright and dusty galaxies are present and indicate that the early evolution of galaxies around the quasar is not simultaneous. In addition, we discovered 31 [O III] emitters in this field at other redshifts, 5.3 < z < 6.7, with half of them situated at z ~ 5.4 and 6.2. This indicates that star-forming galaxies, such as [O III] emitters, are generally clustered at high redshifts. These discoveries demonstrate the unparalleled redshift survey capabilities of NIRCam WFSS and the potential of the full ASPIRE survey data set.

Keywords: early universe; galaxies; protoclusters; redshift surveys; supermassive black holes
Progenitor Constraint with Circumstellar Material for the Magnetar-hosting Supernova Remnant RCW 103

Stellar winds blown out from massive stars (≳10 M ⊙) contain precious information on the progenitor itself, and in this context the most important elements are carbon (C), nitrogen (N), and oxygen (O), which are produced by the CNO cycle in the H-burning layer. Although their X-ray fluorescence lines are expected to be detected in swept-up shock-heated circumstellar materials in supernova remnants, those of C and N have been particularly difficult to detect so far. Here, we present high-resolution spectroscopy of the young magnetar-hosting supernova remnant RCW 103 with the Reflection Grating Spectrometer on board XMM-Newton and report on the detection of the N VII Lyα (0.50 keV) line for the first time. By comparing the obtained abundance ratio of N to O (N/O = 3.8 ± 0.1) with various stellar evolution models, we show that the progenitor of RCW 103 is likely to have a low mass (10-12 M ⊙) and medium rotation velocity (≲100 km s-1). The results also rule out the possibility of dynamo effects in massive (≥35 M ⊙) stars as a mechanism for forming the associated magnetar 1E 161348-5055. Our method is useful for estimating various progenitor parameters for future missions with microcalorimeters such as XRISM and Athena.

Keywords: supernova remnants; interstellar medium; x-ray sources; high energy astrophysics; circumstellar matter; stellar evolution
The Solar Neighborhood LI: A Variability Survey of Nearby M Dwarfs with Planets from Months to Decades with TESS and the CTIO/SMARTS 0.9 m Telescope

We present the optical photometric variability of 32 planet-hosting M dwarfs within 25 pc over timescales of months to decades. The primary goal of this project—A Trail to Life Around Stars (ATLAS)—is to follow the trail to life by revealing nearby M dwarfs with planets that are also "quiet," which may make them more amiable to habitability. There are 69 reported exoplanets orbiting the 32 stars discussed here, providing a rich sample of worlds for which environmental evaluations are needed. We examine the optical flux environments of these planets over month-long timescales for 23 stars observed by TESS, and find that 17 vary by less than 1% (∼11 mmag). All 32 stars are being observed at the CTIO/SMARTS 0.9 m telescope, with a median duration of 19.1 yr of optical photometric data in the VRI bands. We find over these extended timescales that six stars show optical flux variations less than 2%, 25 vary from 2% to 6% (∼22–67 mmag), and only one, Proxima Centauri, varies by more than 6%. Overall, LHS 1678 exhibits the lowest optical variability levels measured over all timescales examined, thereby providing one of the most stable photometric environments among the planets reported around M dwarfs within 25 pc. More than 600 of the nearest M dwarfs are being observed at the 0.9 m telescope in the RECONS program that began in 1999, and many more planet hosts will undoubtedly be revealed, providing more destinations to be added to the ATLAS sample in the future.

Keywords: exoplanet systems; habitable planets; m dwarf stars; planet hosting stars; solar neighborhood; surveys; exoplanet surface variability; stellar activity
Betelgeuse Just Is Not That Cool: Effective Temperature Alone Cannot Explain the Recent Dimming of Betelgeuse

We present optical spectrophotometry of the red supergiant (RSG) Betelgeuse from 2020 February 15, during its recent unprecedented dimming episode. By comparing this spectrum to stellar atmosphere models for cool supergiants, as well as spectrophotometry of other Milky Way RSGs, we conclude that Betelgeuse has a current effective temperature of 3600 ± 25 K. While this is slightly cooler than previous measurements taken prior to Betelgeuse's recent lightcurve evolution, this drop in effective temperature is insufficient to explain Betelgeuse's recent optical dimming. We propose that episodic mass loss and an increase in the amount of large-grain circumstellar dust along our sightline to Betelgeuse is the most likely explanation for its recent photometric evolution.

Keywords: m supergiant stars; stellar atmospheres; circumstellar dust
Proton Energization by Phase Steepening of Parallel-propagating Alfvénic Fluctuations

Proton energization at magnetic discontinuities generated by phase-steepened fronts of parallel-propagating, large-amplitude Alfvénic fluctuation is studied using hybrid simulations. We find that dispersive effects lead to the collapse of the wave via phase steepening and the subsequent generation of compressible fluctuations that mediate an efficient local energy transfer from the wave to the protons. Proton scattering at the steepened edges causes nonadiabatic proton perpendicular heating. Furthermore, the parallel electric field at the propagating fronts mediates the acceleration of protons along the mean field. A steady-state is achieved where the proton distribution function displays a field-aligned beam at the Alfvén speed, and compressible fluctuations are largely damped. We discuss the implications of our results in the context of Alfvénic solar wind.

Keywords: alfven waves; interplanetary discontinuities; interplanetary particle acceleration; interplanetary turbulence
Biasing Relation, Environmental Dependencies, and Estimation of the Growth Rate from Star-forming Galaxies

The connection between galaxy star formation rate (SFR) and dark matter (DM) is of paramount importance for the extraction of cosmological information from next-generation spectroscopic surveys that will target emission line star-forming galaxies. Using publicly available mock galaxy catalogs obtained from various semianalytic models (SAMs), we explore the SFR-DM connection in relation to the speed-from-light method for inferring the growth rate, f, from luminosity/SFR shifts. Emphasis is given to the dependence of the SFR distribution on the environmental density on scales of 10-100 s Mpc. We show that the application of the speed-from-light method to a Euclid-like survey is not biased by environmental effects. In all models, the precision on the measured β = f/b parameter is σβ ≲ 0.17 at z = 1. This translates into errors of σf ∼ 0.22 and ${\sigma }_{(f{\sigma }_{8})}\sim 0.1$ without invoking assumptions on the mass power spectrum. These errors are in the same ballpark as recent analyses of the redshift space distortions in galaxy clustering. In agreement with previous studies, the bias factor, b, is roughly a scale-independent, constant function of the SFR for star-forming galaxies. Its value at z = 1 ranges from 1.2 to 1.5 depending on the SAM recipe. Although in all SAMs, denser environments host galaxies with higher stellar masses, the dependence of the SFR on the environment is more involved. In most models, the SFR probability distribution is skewed to larger values in denser regions. One model exhibits an inverted trend, where high SFR is suppressed in dense environments.

Keywords: cosmology