adsabs/SciX_UAT_keywords huggingface dataset:
On the Correlation between Atomic Gas and Bars in Galaxies

We analyze the correlation between properties of large-scale bars and atomic gas content of galaxies to explore the role of H I gas on bar evolution in galaxies. We show that the absolute bar size depends strongly on total stellar mass of galaxies and does not change significantly with H I gas fraction at fixed stellar mass. Furthermore, the physical size of the bar is small and nearly constant in high H I gas fraction and low-mass galaxies and becomes larger with increasing galactic stellar mass in low gas fraction galaxies. When the stellar masses are fixed, the relative bar length normalized to the disk shows a decrease with increasing H I gas fraction due to the larger disks in gas-richer galaxies. We measure the gas deficiency of the samples and find that the gas-rich galaxies have longer and stronger bars compared with the H I gas-deficient galaxies at fixed stellar mass, especially for the massive ones. When splitting the samples into star-forming and quiescent subgroups, the star-forming galaxies tend to have longer bars than the quiescent ones at fixed stellar mass and gas deficiency. In addition, our results suggest two different types of bar properties, in which the bars in gas-rich galaxies grow longer but retain similar axial ratio over time, while they grow longer and fatter over time in gas-poor galaxies.

Keywords: barred spiral galaxies; galaxy evolution; interstellar atomic gas; star formation
Parallel Diffusion Coefficient of Energetic Charged Particles in the Inner Heliosphere from the Turbulent Magnetic Fields Measured by Parker Solar Probe

Diffusion coefficients of energetic charged particles in turbulent magnetic fields are a fundamental aspect of diffusive transport theory but remain incompletely understood. In this work, we use quasi-linear theory to evaluate the spatial variation of the parallel diffusion coefficient κ ∥ from the measured magnetic turbulence power spectra in the inner heliosphere. We consider the magnetic field and plasma velocity measurements from Parker Solar Probe made during Orbits 5–13. The parallel diffusion coefficient is calculated as a function of radial distance from 0.062 to 0.8 au, and the particle energy from 100 keV to 1 GeV. We find that κ ∥ increases exponentially with both heliocentric distance and energy of particles. The fluctuations in κ ∥ are related to the episodes of large-scale magnetic structures in the solar wind. By fitting the results, we also provide an empirical formula of κ ∥ = (5.16 ± 1.22) × 1018 r 1.17±0.08 E 0.71±0.02 (cm2 s‑1) in the inner heliosphere, which can be used as a reference in studying the transport and acceleration of solar energetic particles as well as the modulation of cosmic rays.

Keywords: solar energetic particles; interplanetary turbulence
A Visually Classified Spectroscopic Object Catalog for SDSS-IV MaNGA

We provide a catalog of visually classified objects in the MaNGA integral field spectroscopic survey. The MaNGA survey is designed to target a single galaxy with each of its integral field units; however, many of these fields will host ancillary objects. We identify these discrete objects by cleaning up SDSS photometric objects in MaNGA's fields-of-view. We then use the spectra from MaNGA's data cubes to spectrally classify the identified objects. The catalog contains the positions and classifications of 1385 stars, 11,439 galaxies, and 107 broad-line active galactic nucleus (BLAGN) from the 10,130 unique MaNGA fields. We also provide spectroscopically derived parameters for the galaxies including; stellar masses, gas and stellar kinematics, and emission-line fluxes and equivalent widths. This catalog effectively expands the size of the MaNGA catalog by ~50%, increasing the utility of the MaNGA project.

Keywords: galaxies
The NANOGrav 11 yr Data Set: Limits on Supermassive Black Hole Binaries in Galaxies within 500 Mpc

Supermassive black hole binaries (SMBHBs) should form frequently in galactic nuclei as a result of galaxy mergers. At subparsec separations, binaries become strong sources of low-frequency gravitational waves (GWs), targeted by Pulsar Timing Arrays. We used recent upper limits on continuous GWs from the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) 11 yr data set to place constraints on putative SMBHBs in nearby massive galaxies. We compiled a comprehensive catalog of ~44,000 galaxies in the local universe (up to redshift ~0.05) and populated them with hypothetical binaries, assuming that the total mass of the binary is equal to the SMBH mass derived from global scaling relations. Assuming circular equal-mass binaries emitting at NANOGrav's most sensitive frequency of 8 nHz, we found that 216 galaxies are within NANOGrav's sensitivity volume. We ranked the potential SMBHBs based on GW detectability by calculating the total signal-to-noise ratio such binaries would induce within the NANOGrav array. We placed constraints on the chirp mass and mass ratio of the 216 hypothetical binaries. For 19 galaxies, only very unequal-mass binaries are allowed, with the mass of the secondary less than 10% that of the primary, roughly comparable to constraints on an SMBHB in the Milky Way. However, we demonstrated that the (typically large) uncertainties in the mass measurements can weaken the upper limits on the chirp mass. Additionally, we were able to exclude binaries delivered by major mergers (mass ratio of at least 1/4) for several of these galaxies. We also derived the first limit on the density of binaries delivered by major mergers purely based on GW data.

Keywords: galaxies; supermassive black holes; gravitational waves
Revisiting the Fundamental Parameters of 49 New Star Clusters in Gaia DR2

Reliable fundamental parameters of star clusters such as distance modulus, metallicity, age, extinction, and binary fraction are of key importance for astrophysical studies. Although a lot of new star clusters were identified from the data of, e.g., Gaia Data Release 2 (Gaia DR2), the fundamental parameters of many clusters were not determined reliably. This work makes use of the photometry data of Gaia DR2 and a good color-magnitude diagram (CMD) analysis tool, Powerful CMD, to determine the fundamental parameters of 49 new star clusters in detail. All CMDs are fitted carefully by both statistics and by eye, to make sure the CMDs are reproduced as well as possible. As a result, the fundamental parameters of 22 clusters are determined reliably, and those of the others are also determined as well as we can. Because the width of the main sequence in the color direction is used, combined with other widely used CMD features to constrain the fundamental parameters, the results of this work are more reliable than those reported by single-star isochrone fits. As a feature of this work, the primordial binary fractions and rotating star fractions of star clusters have been reported, which are useful for many works, in particular for some simulation research.

Keywords: open star clusters; star clusters
Chandra View of the LINER-type Nucleus in the Radio-loud Galaxy CGCG 292-057: Ionized Iron Line and Jet-ISM Interactions

We present an analysis of the new, deep (94 ksec) Chandra ACIS-S observation of radio-loud active galaxy CGCG 292-057, characterized by a LINER-type nucleus and a complex radio structure that indicates intermittent jet activity. On the scale of the host galaxy bulge, we detected excess X-ray emission with a spectrum best fit by a thermal plasma model with a temperature of ∼0.8 keV. We argue that this excess emission results from compression and heating of the hot diffuse fraction of the interstellar medium displaced by the expanding inner, ∼20 kpc-scale lobes observed in this restarted radio galaxy. The nuclear X-ray spectrum of the target clearly displays an ionized iron line at ∼6.7 keV, and is best fitted with a phenomenological model consisting of a power-law (photon index ≃ 1.8) continuum absorbed by a relatively large amount of cold matter (hydrogen column density ≃0.7 × 1023 cm-2), and partly scattered (fraction ∼3%) by ionized gas, giving rise to a soft excess component and Kα line from iron ions. We demonstrate that the observed X-ray spectrum, particularly the equivalent width of Fe XXV Kα (of order 0.3 keV) can in principle, be explained in a scenario involving a Compton-thin gas located at the scale of the broad-lined region in this source and photoionized by nuclear illumination. We compare the general spectral properties of the CGCG 292-057 nucleus, with those of other nearby LINERs studied in X-rays.

Keywords: x-ray active galactic nuclei; low-luminosity active galactic nuclei; active galaxies; relativistic jets; intergalactic medium; liner galaxies; radio galaxies
A Multiwavelength Investigation of Dust and Stellar Mass Distributions in Galaxies: Insights from High-resolution JWST Imaging

We study the morphological properties of mid-infrared selected galaxies at 1.0 < z < 1.7 in the SMACS J0723.3-7327 cluster field to investigate the mechanisms of galaxy mass assembly and structural formation at cosmic noon. We develop a new algorithm to decompose the dust and stellar components of individual galaxies by using high-resolution images in the MIRI F770W and NIRCam F200W bands. Our analysis reveals that a significant number of galaxies with stellar masses between 109.5 < M */M ⊙ < 1010.5 exhibit dust cores that are relatively more compact than their stellar cores. Specifically, within this mass range, the nonparametric method indicates that the dust cores are 1.23 (±0.05) times more compact than the stellar cores on average when evaluated with flux concentration of the two components within a fixed radius. Similarly, the parametric method yields an average compactness ratio of 1.27 (±0.06). Notably, the most massive galaxy (M * ~ 1010.9 M ⊙) in our sample demonstrates a comparable level of compactness between its stellar core and dust, with a dust-to-stellar ratio of 0.86 (0.89) as derived from nonparametric (parametric) method. The observed compactness of the dust component is potentially attributed to the presence of a (rapidly growing) massive bulge that in some cases is associated with elevated star formation. Expanding the sample size through a joint analysis of multiple Cycle 1 deep-imaging programs can help to confirm the inferred picture. Our pilot study highlights that MIRI offers an efficient approach to studying the structural formation of galaxies from cosmic noon to the modern Universe.

Keywords: galaxy evolution; interstellar medium; galaxy bulges; galaxy structure
A SOFIA Survey of [C II] in the Galaxy M51. II. [C II] and CO Kinematics across the Spiral Arms

We present the first complete, velocity-resolved [C II] 158 μm image of the M51 grand-design spiral galaxy, observed with the upgraded German Receiver for Astronomy at Terahertz frequencies instrument on the Stratospheric Observatory for Infrared Astronomy. [C II] is an important tracer of various phases of the interstellar medium (ISM), including ionized gas, neutral atomic, and diffuse molecular regions. We combine the [C II] data with H I, CO, 24 μm dust continuum, FUV, and NIR K-band observations to study the evolution of the ISM across M51's spiral arms in both position-position and position-velocity space. Our data show strong velocity gradients in H I, 12CO, and [C II] at the locations of the stellar arms (traced by K-band data) with a clear offset in position-velocity space between upstream molecular gas (traced by 12CO) and downstream star formation (traced by [C II]). We compare the observed position-velocity maps across the spiral arms with synthetic observations from numerical simulations of galaxies with both dynamical and quasi-stationary steady spiral arms that predict both tangential and radial velocities at the location of the spiral arms. We find that our observations, based on the observed velocity gradients and associated offset between CO and [C II], are consistent with the presence of shocks in the spiral arms in the inner parts of M51 and in the arm connecting the companion galaxy, M51b, in the outer parts of M51.

Keywords: interstellar medium; galaxies; galactic and extragalactic astronomy
Magnetofrictional Modeling of an Erupting Pseudostreamer

In this study, we present the magnetic configuration of an erupting pseudostreamer observed on 2015 April 19, on the southwest limb of the Sun, with a prominence cavity embedded inside. The eruption resulted in a partial halo coronal mass ejection. The prominence eruption begins with a slow rise and then evolves to a fast-rise phase. We analyze this erupting pseudostreamer using the flux-rope insertion method and magnetofrictional relaxation to establish a sequence of plausible out-of-equilibrium magnetic configurations. This approach allows the direct incorporation of observations of structures seen in the corona (filament and cavity) to appropriately model the pseudostreamer based on SDO/HMI line-of-sight photospheric magnetograms. We also perform a topological analysis in order to determine the location of quasiseparatrix layers (QSLs) in the models, producing Q-maps to examine how the QSL locations progress in the higher iterations. We found that the axial flux in our best-fit unstable model was a factor of 20 times higher than we found in our marginally stable case. We computed the average magnetic field strength of the prominence and found that the unstable model exhibits twice the average field strength of the stable model. The eruption height from our modeling matches very well with the prominence eruption height measured from the AIA observation. The Q-maps derived from the model reproduce structures observed in LASCO/C2. Thus, the modeling and topological analysis results are fully consistent with the observed morphological features, implying that we have captured the large magnetic structure of the erupting filament in our magnetofrictional simulation.

Keywords: solar corona
Search for Galactic Civilizations Using Historical Supernovae

We study an interstellar signaling scheme that was originally proposed by Seto and efficiently links intentional transmitters to extraterrestrial intelligence (ETI) searchers through a conspicuous astronomical burst, without prior communication. Based on the geometrical and game theoretic viewpoints, the scheme can be refined so that intentional signals can be sent and received after observing a reference burst, in contrast to the original proposal (before observing a burst). Given this inverted temporal structure, Galactic supernovae recorded in the past 2000 yr can be regarded as interesting guideposts for an ETI search. While the best use period of SN 393 has presumably passed ~100 yr ago, some of the historical supernovae might allow us to compactify the ETI survey regions down to less than one present of 4π, around two rings in the sky.

Keywords: search for extraterrestrial intelligence
UNCOVER: A NIRSpec Identification of a Broad-line AGN at z = 8.50

Deep observations with the James Webb Space Telescope (JWST) have revealed an emerging population of red pointlike sources that could provide a link between the postulated supermassive black hole seeds and observed quasars. In this work, we present a JWST/NIRSpec spectrum from the JWST Cycle 1 UNCOVER Treasury survey of a massive accreting black hole at z = 8.50 displaying a clear broad-line component as inferred from the Hβ line with FWHM = 3439 ± 413 km s-1, typical of the broad-line region of an active galactic nucleus (AGN). The AGN nature of this object is further supported by high ionization, as inferred from emission lines, and a point-source morphology. We compute a black hole mass of ${\mathrm{log}}_{10}({M}_{\mathrm{BH}}/{M}_{\odot })=8.17\pm 0.42$ and a bolometric luminosity of L bol ~ 6.6 × 1045 erg s-1. These values imply that our object is accreting at ~40% of the Eddington limit. Detailed modeling of the spectral energy distribution in the optical and near-infrared, together with constraints from ALMA, indicate an upper limit on the stellar mass of ${\mathrm{log}}_{10}({M}_{* }/{M}_{\odot })\lt 8.7$ , which would lead to an unprecedented ratio of black hole to host mass of at least ~30%. This is orders of magnitude higher compared to the local QSOs but consistent with recent AGN studies at high redshift with JWST. This finding suggests that a nonnegligible fraction of supermassive black holes either started out from massive seeds and/or grew at a super-Eddington rate at high redshift. Given the predicted number densities of high-z faint AGN, future NIRSpec observations of larger samples will allow us to further investigate galaxy-black hole coevolution in the early Universe.

Keywords: active galactic nuclei; high-redshift galaxies; early universe
A Survey of Interplanetary Small Flux Ropes at Mercury

Interplanetary magnetic flux ropes with durations from a few minutes to a few hours have been termed small flux ropes (SFRs). We have built a comprehensive catalog of SFRs at Mercury using magnetometer data from the orbital phase of the MESSENGER mission (2011-2015). In the absence of solar wind plasma measurements, we developed strict identification criteria for SFRs in the magnetometer observations, including force-free field fits for each flux rope. We identified a total of 48 events that met our strict criteria, with events ranging in duration from 2.5 minutes to 4 hr. Using superposed epoch analysis, we obtained the generic SFR magnetic field profile at Mercury. Due to its eccentric orbit, Mercury's heliospheric distance varies between 0.31 and 0.47 au, a range of ∼0.16 au. This distance is potentially large enough for the SFRs to undergo measurable changes due to distance. Thus, we split the data into two distance bins to look for such changes. We found that the average SFR profile is more symmetric farther from the Sun, in line with the idea that SFRs form closer to the Sun and undergo a relaxation process in the solar wind. Based on this result, as well as the SFR durations and the magnetic field strength fall-off with heliocentric distance, we infer that the SFRs observed at Mercury are expanding as they propagate with the solar wind. We also determined that the SFR occurrence frequency is nearly four times as high at Mercury as for similarly detected events at 1 au. Most interestingly, we found two SFR populations in our data set, one likely generated in a quasi-periodic formation process near the heliospheric current sheet, and the other formed away from the current sheet in isolated events.

Keywords: interplanetary magnetic fields; solar wind; heliosphere
Disk-integrated Thermal Properties of Ceres Measured at Millimeter Wavelengths

We observed Ceres at three epochs in 2015 November and 2017 September and October with Atacama Large Millimeter/submillimeter Array (ALMA) 12 m array and in 2017 October with the ALMA Compact Array (ACA), all at ∼265 GHz continuum (wavelengths of ∼1.1 mm) to map the temperatures of Ceres over a full rotation at each epoch. We also used 2017 October ACA observations to search for HCN. The disk-averaged brightness temperature of Ceres is measured to be between 170 and 180 K during our 2017 observations. The rotational light curve of Ceres shows a double-peaked shape with an amplitude of about 4%. Our HCN search returns a negative result with an upper limit production rate of ∼2 × 1024 molecules s-1, assuming globally uniform production and a Haser model. A thermophysical model suggests that Ceres's top layer has higher dielectric absorption than lunar-like materials at a wavelength of 1 mm. However, previous observations showed that the dielectric absorption of Ceres decreases toward longer wavelengths. Such distinct dielectric properties might be related to the hydrated phyllosilicate composition of Ceres and possibly abundant micrometer-sized grains on its surface. The thermal inertia of Ceres is constrained by our modeling as likely being between 40 and 160 thermal inertia units, much higher than previous measurements at infrared wavelengths. Modeling also suggests that Ceres's light curve is likely dominated by spatial variations in its physical or compositional properties that cause changes in Ceres's observed thermal properties and dielectric absorption as it rotates.

Keywords: ceres; main belt asteroids; small solar system bodies; asteroids
The Ultraviolet Extinction Map and Dust Properties at High Galactic Latitude

Extinction in ultraviolet is much more significant than in optical or infrared, which can be very informative to precisely measure the extinction and understand the dust properties in the low-extinction areas. The high Galactic latitude sky is such an area, important for studying the extragalactic sky and the universe. Based on the stellar parameters measured by the LAMOST and GALAH spectroscopy and the ultraviolet photometry by the Galaxy Evolution Explorer (GALEX) space telescope, the extinction of 1,244,504 stars in the GALEX/near-UV band and 56,123 stars in the GALEX/far-UV band is calculated precisely. The error of color excess is 0.009, 0.128, and 0.454 mag for ${E}_{{G}_{\mathrm{BP}},{G}_{\mathrm{RP}}}$ , ${E}_{\mathrm{NUV},{{\rm{G}}}_{\mathrm{BP}}}$ , and ${E}_{\mathrm{FUV},{{\rm{G}}}_{\mathrm{BP}}}$ , respectively. They delineate the GALEX/near-UV extinction map of about a third of the sky mainly at the high Galactic latitude area with an angular resolution of ∼ 0°4. The mean color excess ratio in the entire sky area is derived to be 3.25, 2.95, and -0.37 for ${E}_{\mathrm{NUV},{{\rm{G}}}_{\mathrm{BP}}}/{E}_{{G}_{\mathrm{BP}},{G}_{\mathrm{RP}}}$ , ${E}_{\mathrm{FUV},{{\rm{G}}}_{\mathrm{BP}}}/{E}_{{G}_{\mathrm{BP}},{G}_{\mathrm{RP}}}$ , and ${E}_{\mathrm{FUV},\mathrm{NUV}}/{E}_{{G}_{\mathrm{BP}},{G}_{\mathrm{RP}}}$ , respectively, which is in general agreement with the previous works, and their changes with the Galactic latitude and the interstellar extinction are discussed.

Keywords: ultraviolet extinction; interstellar dust
Runaway OB Stars in the Small Magellanic Cloud. III. Updated Kinematics and Insights into Dynamical versus Supernova Ejections

We use the kinematics of field OB stars to estimate the frequencies of runaway stars generated by the dynamical ejection scenario (DES), the binary supernova scenario (BSS), and the combined two-step mechanism. We update the proper motions for field OB and OBe stars in the Small Magellanic Cloud (SMC) using Gaia DR3. Our sample now contains 336 stars from the Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC, and we update our algorithm to calculate more accurate velocities compared to those obtained previously from DR2. We find a decrease in median velocity from 39 to 29 km s‑1, implying that the proper motions from our previous work were systematically overestimated. We present the velocity distribution for OBe stars and quantitatively compare it to those of noncompact binaries and high-mass X-ray binaries. We confirm that OBe stars appear to be dominated by the BSS and are likely post-SN binary systems, further supporting the mass-transfer model to explain the origin of their emission-line disks. In contrast, normal OB stars may show a bimodal velocity distribution, which may be expected from different processes that occur with dynamical ejections. The kinematics of fast-rotating OB stars are similar to those of normal OB stars rather than OBe stars, suggesting that the origin of their high ${v}_{r}\sin i$ is different from that of OBe stars. We update our model parameters describing the kinematic origins of the SMC field population, still confirming that for runaway stars, the DES mechanism dominates, and two-step ejections seem comparable in frequency to pure BSS ejections.

Keywords: runaway stars; massive stars; small magellanic cloud; stellar kinematics; interacting binary stars; star clusters; multiple star evolution; be stars; asteroseismology; stellar rotation; high mass x-ray binary stars; oe stars