adsabs/SciX_UAT_keywords huggingface dataset:
The Exploration of Local VolumE Satellites (ELVES) Survey: A Nearly Volume-limited Sample of Nearby Dwarf Satellite Systems

We present the final sample of the Exploration of Local VolumE Satellites (ELVES) survey, a survey of the dwarf satellites of a nearly volume-limited sample of Milky Way (MW)-like hosts in the Local Volume. Hosts are selected simply via a cut in luminosity ( ${M}_{{K}_{s}}\lt -22.1$ mag) and distance (D < 12 Mpc). We cataloged the satellites of 25 of the 31 such hosts, with another five taken from the literature. All hosts are surveyed out to at least 150 projected kpc ( ~ R vir/2), with the majority surveyed to 300 kpc ( ~ R vir). Satellites are detected using a consistent semiautomated algorithm specialized for low surface brightness dwarfs. As shown through extensive tests with injected galaxies, the catalogs are complete to M V ~ -9 mag and μ 0,V ~ 26.5 mag arcsec-2. Candidates are confirmed to be real satellites through distance measurements including redshift, tip of the red giant branch, and surface brightness fluctuations. Across all 30 surveyed hosts, there are 338 confirmed satellites with M V < -9 mag, with a further 106 candidates awaiting distance measurement. For the vast majority of these, we provide consistent multiband Sérsic photometry. We show that satellite abundance correlates with host mass, with the MW being quite typical among comparable systems, and that satellite quenched fraction rises steeply with decreasing satellite mass, mirroring the quenched fraction for the MW and M31. The ELVES survey represents a massive increase in the statistics of surveyed systems with known completeness, and the provided catalogs are a unique data set to explore various aspects of small-scale structure and dwarf galaxy evolution.

Keywords: dwarf galaxies; low surface brightness galaxies; local group; galaxy groups
Early-growing Supermassive Black Holes Strengthen Bars and Boxy/Peanut Bulges

Using N-body simulations, we explore the effects of growing a supermassive black hole (SMBH) prior to or during the formation of a stellar bar. Keeping the final mass and growth rate of the SMBH fixed, we show that if it is introduced before or while the bar is still growing, the SMBH does not cause a decrease in bar amplitude. Rather, in most cases, it is strengthened. In addition, an early-growing SMBH always either decreases the buckling amplitude, delays buckling, or both. This weakening of buckling is caused by an increase in the disk vertical velocity dispersion at radii well beyond the nominal black hole sphere of influence. While we find considerable stochasticity and sensitivity to initial conditions, the only case where the SMBH causes a decrease in bar amplitude is when it is introduced after the bar has attained a steady state. In this case, we confirm previous findings that the decrease in bar strength is a result of scattering of bar-supporting orbits with small pericenter radii. By heating the inner disk both radially and vertically, an early-growing SMBH increases the fraction of stars that can be captured by the inner Lindblad resonance (ILR) and the vertical ILR, thereby strengthening both the bar and the boxy-peanut-shaped bulge. Using orbital frequency analysis of star particles, we show that when an SMBH is introduced early and the bar forms around it, the bar is populated by different families of regular bar-supporting orbits than when the bar forms without an SMBH.

Keywords: galaxy evolution; barred spiral galaxies; supermassive black holes; galaxy bulges; galaxy bars; galaxy nuclei; n-body simulations; orbital resonances
Follow-up Studies of Five Cataclysmic Variable Candidates Discovered by LAMOST

We report follow-up observations of five cataclysmic variable candidates from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) published by Hou et al. LAMOST J024048.51+195226.9 is the most unusual of the five; an early-M type secondary star contributes strongly to its spectrum, and its spectral and photometric behavior are strikingly reminiscent of the hitherto-unique propeller system AE Aqr. We confirm that a 7.34 hr period discovered in the Catalina survey data is orbital. Another object, LAMOST J204305.95+341340.6, appears to be a near twin of the novalike variable V795 Her, with an orbital period in the so-called 2-3 hr "gap." LAMOST J035913.61+405035.0 is evidently an eclipsing, weakly outbursting dwarf nova with a 5.48 hr period. Our spectrum of LAMOST J090150.09+375444.3 is dominated by a late-type secondary and shows weak, narrow Balmer emission moving in phase with the absorption lines, but at lower amplitude; we do not see the He II λ4686 emission evident in the published discovery spectrum. We again confirm that a period from the Catalina data, in this case 6.80 hr, is orbital. LAMOST J033940.98+414805.7 yields a radial-velocity period of 3.54 hr, and its spectrum appears to be typical of novalike variables in this period range. The spectroscopically selected sample from LAMOST evidently includes some interesting cataclysmic variables that have been unrecognized until now, apparently because of the relatively modest range of their photometric variations.

Keywords: cataclysmic variable stars; nova-like variable stars; eclipsing binary stars
ALMA Observations of the DART Impact: Characterizing the Ejecta at Submillimeter Wavelengths

We report observations of the Didymos-Dimorphos binary asteroid system using the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Compact Array (ACA) in support of the Double Asteroid Redirection Test mission. Our observations on UT 2022 September 15 provided a preimpact baseline and the first measure of Didymos-Dimorphos's spectral emissivity at λ = 0.87 mm, which was consistent with the handful of siliceous and carbonaceous asteroids measured at millimeter wavelengths. Our postimpact observations were conducted using four consecutive executions each of ALMA and the ACA spanning from T+3.52 to T+8.60 hr, sampling thermal emission from the asteroids and the impact ejecta. We scaled our preimpact baseline measurement and subtracted it from the postimpact observations to isolate the flux density of millimeter-sized grains in the ejecta. Ejecta dust masses were calculated for a range of materials that may be representative of Dimorphos's S-type asteroid material. The average ejecta mass over our observations is consistent with 1.3-6.4 × 107 kg, with the lower and higher values calculated for amorphous and crystalline silicates, respectively. Owing to the likely crystalline nature of S-type asteroid material, the higher value is favored. These ejecta masses represent 0.3%-1.5% of Dimorphos's total mass and are in agreement with lower limits on the ejecta mass based on measurements at optical wavelengths. Our results provide the most sensitive measure of millimeter-sized material in the ejecta and demonstrate the power of ALMA for providing supporting observations to spaceflight missions.

Keywords: asteroids; near-earth objects; radio astronomy; radio interferometry; high resolution spectroscopy; impact phenomena
Physics and Chemistry of Radiation Driven Cloud Evolution. [C II] Kinematics of IC 59, and IC 63

We used high-resolution [C II] 158 μm mapping of two nebulae IC 59 and IC 63 from SOFIA/upGREAT in conjunction with ancillary data of the gas, dust, and polarization to probe the kinematics, structure, and magnetic properties of their photodissociation regions (PDRs). The nebulae are part of the Sh 2-185 H II region that is illuminated by the B0 IVe star γ Cas. The velocity structure of each PDR changes with distance from γ Cas, which is consistent with driving by the radiation. Based on previous far-ultraviolet (FUV) flux measurements of, and the known distance to, γ Cas, along with the predictions of 3D distances to the clouds, we estimated the FUV radiation field strength (G 0) at the clouds. Assuming negligible extinction between the star and clouds, we find their 3D distances from γ Cas. For IC 63, our results are consistent with earlier estimates of distance from Andersson et al., locating the cloud at ~2 pc from γ Cas at an angle of 58° to the plane of the sky behind the star. For IC 59, we derive a distance of 4.5 pc at an angle of 70° in front of the star. We do not detect any significant correlation between the orientation of the magnetic field and the velocity gradients of [C II] gas, which indicates a moderate magnetic field strength. The kinetic energy in IC 63 is estimated to be an order of 10 higher than the magnetic energies. This suggests that kinetic pressure in this nebula is dominant.

Keywords: nebulae; interstellar dust
COOL-LAMPS. III. Discovery of a 25.″9 Separation Quasar Lensed by a Merging Galaxy Cluster

In the third paper from the COOL-LAMPS Collaboration, we report the discovery of COOL J0542-2125, a gravitationally lensed quasar at z = 1.84, observed as three images due to an intervening massive galaxy cluster at z = 0.61. The lensed quasar images were identified in a search for lens systems in recent public optical imaging data and have separations on the sky up to 25.″9, wider than any previously known lensed quasar. The galaxy cluster acting as a strong lens appears to be in the process of merging, with two subclusters separated by ~1 Mpc in the plane of the sky, and their central galaxies showing a radial velocity difference of ~1000 km s-1. Both cluster cores show strongly lensed images of an assortment of background sources, as does the region between them. A preliminary strong lens model implies masses of ${M}_{\lt 250{\rm{k}}{\rm{p}}{\rm{c}}}={1.79}_{-0.01}^{+0.16}\times {10}^{14}\,{M}_{\odot }$ and ${M}_{\lt 250{\rm{k}}{\rm{p}}{\rm{c}}}={1.48}_{-0.10}^{+0.04}\times {10}^{14}\,{M}_{\odot }$ for the east and west subclusters, respectively. This line of sight is also coincident with an ROSAT ALL-sky Survey source, centered between the two confirmed cluster halos reminiscent of other major cluster-scale mergers. Archival and new follow-up imaging show flux variability in the quasar images of up to 0.4 mag within ~1 yr, and new multicolor imaging data reveal a 2σ detection of the underlying quasar host. A lens system with this configuration offers rare opportunities for a range of future studies of both the lensed quasar and its host and the foreground cluster merger causing the lensing. * This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile, and the 2.5 m Nordic Optical Telescope located at Rocque de los Muchachos Observatory, La Palma.

Keywords: strong gravitational lensing; hubble constant; quasars; galaxy clusters; high-redshift galaxies; agn host galaxies
Revealing the Accretion Physics of Supermassive Black Holes at Redshift z ∼ 7 with Chandra and Infrared Observations

X-ray emission from quasars has been detected up to redshift z = 7.5, although only limited to a few objects at z > 6.5. In this work, we present new Chandra observations of five z > 6.5 quasars. By combining with archival Chandra observations of six additional z > 6.5 quasars, we perform a systematic analysis on the X-ray properties of these earliest accreting supermassive black holes (SMBHs). We measure the black hole masses, bolometric luminosities (Lbol), Eddington ratios (λEdd), emission line properties, and infrared luminosities (LIR) of these quasars using infrared and submillimeter observations. Correlation analysis indicates that the X-ray bolometric correction (the factor that converts from X-ray luminosity to bolometric luminosity) decreases with increasing Lbol, and that the UV/optical-to-X-ray ratio, αox, strongly correlates with L2500 Å, and moderately correlates with λEdd and blueshift of C IV emission lines. These correlations are consistent with those found in lower-z quasars, indicating quasar accretion physics does not evolve with redshift. We also find that LIR does not correlate with L2-10 keV in these luminous distant quasars, suggesting that the ratio of the SMBH growth rate and their host galaxy growth rate in these early luminous quasars are different from those of local galaxies. A joint spectral analysis of the X-ray detected z > 6.5 quasars yields an average X-ray photon index of ${\rm{\Gamma }}={2.32}_{-0.30}^{+0.31}$ , steeper than that of low-z quasars. By comparing it with the Γ - λEdd relation, we conclude that the steepening of Γ for quasars at z > 6.5 is mainly driven by their higher Eddington ratios.

Keywords: quasars; early universe; x-ray quasars; high-luminosity active galactic nuclei; supermassive black holes
NOEMA Observations of CO Emission in Arp 142 and Arp 238

Previous studies have shown significant differences in the enhancement of the star formation rate (SFR) and star formation efficiency (SFE = SFR/Mmol) between spiral-spiral and spiral-elliptical mergers. In order to shed light on the physical mechanism of these differences, we present NOEMA observations of the molecular gas distribution and kinematics (linear resolutions of ~2 kpc) in two representative close major-merger star-forming pairs: the spiral-elliptical pair Arp 142 and the spiral-spiral pair Arp 238. The CO in Arp 142 is widely distributed over a highly distorted disk without any nuclear concentration, and an off-center ringlike structure is discovered in channel maps. The SFE varies significantly within Arp 142, with a starburst region (region 1) near the eastern tip of the distorted disk showing an SFE ~ 0.3 dex above the mean of the control sample of isolated galaxies and the SFE of the main disk (region 4) 0.43 dex lower than the mean of the control sample. In contrast, the CO emission in Arp 238 is detected only in two compact sources at the galactic centers. Compared to the control sample, Arp 238-E shows an SFE enhancement of more than 1 dex, whereas Arp 238-W has an enhancement of ~0.7 dex. We suggest that the extended CO distribution and large SFE variation in Arp 142 are due to an expanding large-scale ring triggered by a recent high-speed head-on collision between the spiral galaxy and the elliptical galaxy, and the compact CO sources with high SFEs in Arp 238 are associated with nuclear starbursts induced by gravitational tidal torques in a low-speed coplanar interaction.

Keywords: galaxy pairs; interacting galaxies; galaxies; galaxy collisions; galaxy mergers
Dependence of Cosmological Constraints on Gray Photometric Zero-point Uncertainties of Supernova Surveys

Type Ia supernova (SN) measurements of the Hubble constant, H 0; cosmic mass density, Ω M ; and dark energy equation-of-state parameter, w, rely on heterogeneous SN surveys across three decades of observation. These distinct surveys may have undiagnosed, relative photometric zero-point errors. We determine the sensitivities of the SH0ES+Pantheon+ cosmological constraints to unknown gray systematics in the photometric zero-point calibration between the 19 surveys that comprise the Pantheon+ SN compendium. Varying the surveys' gray zero-points simultaneously with cosmological parameters, we determine that the SH0ES+Pantheon+ measurement of H 0 is robust against gray intersurvey photometric miscalibration. Specifically, uncalibrated intersurvey systematics could represent a source of uncertainty no larger than 0.39 km s-1 Mpc-1 for H 0. This modest increase in H 0 uncertainty could not account for the 7 km s-1 Mpc-1 "Hubble tension" between the SH0ES measurement of H 0 and the Planck ΛCDM-based inference of H 0. However, the SH0ES+Pantheon+ best-fit values of Ω M and w are not robust against gray zero-point error, slipping by up to 0.16 and -0.63. Because measurements of Ω M and w depend on intrasurvey cross-band calibration, the hypothetical gray miscalibration underestimates the sensitivity of these measurements to zero-point miscalibration. Because the Pantheon+ compendium contains many surveys that share low-z Hubble flow (HF) and Cepheid-paired SNe, intersurvey photometric calibration errors do not significantly impede the joint use of SH0ES and Pantheon+ to measure H 0 to 1% accuracy. However, H 0 constraints that rely on one HF survey but numerous galactic distance calibration surveys are susceptible to intersurvey photometric miscalibration.

Keywords: cosmology; type ia supernovae; flux calibration; hubble constant; dark energy; astronomy data analysis
Self-calibrating Interloper Bias in Spectroscopic Galaxy-clustering Surveys

Contamination of interloper galaxies due to misidentified emission lines can be a big issue in spectroscopic galaxy-clustering surveys, especially in future high-precision observations. We propose a statistical method based on the cross correlations of the observational data between two redshift bins to efficiently reduce this effect, and it can also derive the interloper fraction fi in a redshift bin with a high level of accuracy. The ratio of cross and autoangular correlation functions or power spectra between redshift bins are suggested to estimate fi, and the key equations are derived for theoretical discussion. In order to explore and prove the feasibility and effectiveness of this method, we also run simulations, generate mock data, and perform cosmological constraints considering systematics based on the observation of China Space Station Telescope. We find that this method can effectively reduce the interloper effect, and accurately constrain the cosmological parameters for fi < 1% ~ 10%, which is suitable for most future surveys. This method can also be applied to other kinds of galaxy-clustering surveys like line intensity mapping.

Keywords: cosmology; large-scale structure of the universe; cosmological parameters
Practical Stereophotoclinometry for Modeling Shape and Topography on Planetary Missions

Stereophotoclinometry (SPC) is a technique to extract topographic information from images acquired by spacecraft. It combines stereophotogrammetry and photoclinometry to produce a product that has the accuracy of stereo with the resolution of photoclinometry without the restrictions common to both. We describe the implementation of this technique in the context of digital terrain model (DTM) generation for a small-body mission. We detail the process and the data used to generate SPC-derived DTMs at progressively increasing resolutions. The highest-quality DTMs are generated using four images optimized for topography, a 30° emission angle with the emission azimuth (spacecraft position) to the north, east, south, and west of the target, and one image optimized for albedo (a low incidence angle such that most of the image pixels' digital numbers are based upon albedo rather than topography). We discuss implications for mission planning and how SPC-based DTM generation can support spacecraft navigation. As a case study, we share outcomes from the modeling performed for the OSIRIS-REx mission to asteroid Bennu.

Keywords: asteroids
Weak Bidirectional Outflows and Flare Current Sheet in a Solar Coronal Jet Driven by the Eruption of a Minifilament

Different from the classical emerging-flux model for solar jets, recent studies proposed that the great majority of solar coronal jets are triggered by minifilament eruptions and two magnetic reconnection processes should take place during the course, named as external reconnection (breakout reconnection) and internal reconnection (flare reconnection). With the excellent data of the Solar Dynamics Observatory, we present the observational signatures of these two magnetic reconnection processes during a solar coronal jet that occurred in a huge coronal hole of northern hemisphere. The jet was triggered by the eruption of a minifilament that located at a coronal bright point in the coronal hole. Weak bidirectional outflows were observed when the erupting minifilament approached the ambient open field, ejecting along the triggered jet spire and the jet base simultaneously. In addition, a flare current sheet occurred after the eruption of the minifilament, connecting the jet spire and the jet bright point (or flare). We suggest the occurrence of the weak bidirectional outflows and the flare current sheet correspond to the external and the internal reconnections, respectively. Prior to the eruption of the minifilament and the jet, photospheric magnetic flux cancellation maintained for more than 7 hr in the source region, and the positive flux decreased for about 28.6% during this period. So, consistent with the recent observations, the trigger mechanism of the minifilament eruption and the following jet in this event may be flux cancellation rather than flux emergence.

Keywords: solar activity; solar coronal holes; solar filament eruptions; solar magnetic fields
Predictions for Strong-lens Detections with the Nancy Grace Roman Space Telescope

Strong gravitational lensing is an ideal tool for mapping the distribution of dark matter and for testing the values of cosmological parameters. Forthcoming surveys such as Euclid and the Rubin Observatory Large Synoptic Telescope Survey should increase the number of known strong lensing systems significantly, with for example over 100,000 such systems predicted in the Euclid wide survey. In this short research note we predict that approximately 17,000 strong gravitational lenses will also be detectable in the Nancy Grace Roman Space Telescope 2000 square degree survey, using the LensPop gravitational lensing model. We present predicted distributions in source and deflector redshifts, magnitudes, and magnifications. Although this survey is not primarily designed as a strong lensing detection experiment, it will still provide a large complementary catalog to shallower, wider-area forthcoming lensing discovery projects.

Keywords: galaxy evolution; strong gravitational lensing; cosmology; infrared astronomy; observational astronomy
Solving the Traveling Telescope Problem with Mixed-integer Linear Programming

The size and complexity of modern astronomical surveys has grown to the point where, in many cases, traditional human scheduling of observations are tedious at best and impractical at worst. Automated scheduling algorithms present an opportunity to save human effort and increase scientific productivity. A common scheduling challenge involves determining the optimal ordering of a set of targets over a night subject to timing constraints and time-dependent slew overheads. We present a solution to the "traveling telescope problem" that uses mixed-integer linear programming. This algorithm is fast enough to enable dynamic schedule generation in many astronomical contexts. It can determine the optimal solution for 100 observations within 10 minutes on a modern workstation, reducing slew overheads by a factor of 5 compared to random ordering. We also provide a heuristic method that can return a near-optimal solution at significantly reduced computational cost. As a case study, we explore our algorithm's suitability to automatic schedule generation for Doppler planet searches.

Keywords: astronomical methods; observational astronomy