Sazuna/UAT_keywords huggingface dataset:
Systematic KMTNet Planetary Anomaly Search. I. OGLE-2019-BLG-1053Lb, a Buried Terrestrial Planet. In order to exhume the buried signatures of "missing planetary caustics" in Korea Microlensing Telescope Network (KMTNet) data, we conducted a systematic anomaly search of the residuals from point-source point-lens fits, based on a modified version of the KMTNet EventFinder algorithm. This search revealed the lowest-mass-ratio planetary caustic to date in the microlensing event OGLE-2019-BLG-1053, for which the planetary signal had not been noticed before. The planetary system has a planet-host mass ratio of q = (1.25 ± 0.13) × 10-5. A Bayesian analysis yielded estimates of the mass of the host star, ${M}_{\mathrm{host}}={0.61}_{-0.24}^{+0.29}\,{M}_{\odot }$ , the mass of its planet, ${M}_{\mathrm{planet}}={2.48}_{-0.98}^{+1.19}\,{M}_{\oplus }$ , the projected planet-host separation, ${a}_{\perp }={3.4}_{-0.5}^{+0.5}$ au, and the lens distance, ${D}_{{\rm{L}}}={6.8}_{-0.9}^{+0.6}$ kpc. The discovery of this very-low-mass-ratio planet illustrates the utility of our method and opens a new window for a large and homogeneous sample to study the microlensing planet-host mass ratio function down to q ~ 10-5.

Keywords: Exoplanet detection methods, Gravitational microlensing exoplanet detection
Long-term Dynamical Stability in the Outer Solar System. I. The Regular and Chaotic Evolution of the 34 Largest Trans-Neptunian Objects. We carried out an extensive analysis of the stability of the outer solar system, making use of the frequency analysis technique over short-term integrations of nearly 100,000 test particles, as well as a statistical analysis of 200 1 Gyr long numerical simulations, which consider the mutual perturbations of the giant planets and the 34 largest trans-Neptunian objects (we have called all 34 objects "dwarf planets," DPs, even if probably only the largest of them are true DPs). From the frequency analysis, we produced statistical diffusion maps for a wide region of the a-e phase-space plane; we also present the average diffusion time for orbits as a function of perihelion. We later turned our attention to the 34 DPs, making an individualized analysis for each of them and producing a first approximation of their future stability. From the 200 distinct realizations of the orbital evolution of the 34 DPs, we classified the sample into three categories, including 17 stable, 11 unstable, and 6 resonant objects; we also found that, statistically, two objects from the sample will leave the trans-Neptunian region within the next gigayear, most likely being ejected from the solar system, but with a nonnegligible probability of going inside the orbit of Neptune, either to collide with a giant planet or even falling to the inner solar system, where our simulations are no longer able to resolve their continuous evolution.

Keywords: Kuiper belt, Solar system, Dwarf planets, Trans-Neptunian objects, N-body simulations
Constraining Mornings and Evenings on Distant Worlds: A new Semianalytical Approach and Prospects with Transmission Spectroscopy. The technique of transmission spectroscopy-the variation of a planetary radius with wavelength due to opacity sources in the planet's terminator region-has been one of the most successful in the characterization of exoplanet atmospheres to date, providing key insights into the composition and structure of these distant worlds. A common assumption made when using this technique, however, is that the variations are the same in the entire terminator region. In reality, the morning and evening terminators might have distinct temperature, pressure, and thus compositional profiles due to the inherent 3D nature of the planet, which would, in turn, give rise to different spectra on each side of it. Constraining those might be fundamental for our understanding of not only the weather patterns in these distant worlds but also the planetary formation signatures that might only be possible to extract once these features are well understood. Motivated by this physical picture, in this work, we perform a detailed study of the observational prospects of detecting this effect. We present an open-source semianalytical framework with which this information can be extracted directly from transit light curves and perform a detailed study of the prospects of detecting the effect with current missions, such as TESS, and upcoming ones, such as JWST. Our results show that these missions show great promise for the detection of this effect. Transmission spectroscopy studies with JWST, in particular, could provide spectra of each of the limbs, allowing us to convey 3D information previously accessible only via phase curves.

Keywords: Exoplanet astronomy, Exoplanets, Exoplanet atmospheres
Evidence for a Nondichotomous Solution to the Kepler Dichotomy: Mutual Inclinations of Kepler Planetary Systems from Transit Duration Variations. Early analyses of exoplanet statistics from the Kepler mission revealed that a model population of multiplanet systems with low mutual inclinations (~1°-2°) adequately describes the multiple-transiting systems but underpredicts the number of single-transiting systems. This so-called "Kepler dichotomy" signals the existence of a subpopulation of multiplanet systems possessing larger mutual inclinations. However, the details of these inclinations remain uncertain. In this work, we derive constraints on the intrinsic mutual inclination distribution by statistically exploiting transit duration variations (TDVs) of the Kepler planet population. When planetary orbits are mutually inclined, planet-planet interactions cause orbital precession, which can lead to detectable long-term changes in transit durations. These TDV signals are inclination sensitive and have been detected for roughly two dozen Kepler planets. We compare the properties of the Kepler-observed TDV detections to TDV detections of simulated planetary systems constructed from two population models with differing assumptions about the mutual inclination distribution. We find strong evidence for a continuous distribution of relatively low mutual inclinations that is well characterized by a power-law relationship between the median mutual inclination ( ${\tilde{\mu }}_{i,n}$ ) and the intrinsic multiplicity (n): ${\tilde{\mu }}_{i,n}={\tilde{\mu }}_{i,5}{(n/5)}^{\alpha }$ , where ${\tilde{\mu }}_{i,5}={1.10}_{-0.11}^{+0.15}$ and $\alpha =-{1.73}_{-0.08}^{+0.09}$ . These results suggest that late-stage planet assembly and possibly stellar oblateness are the dominant physical origins for the excitation of Kepler planet mutual inclinations.

Keywords: Exoplanet dynamics, Transit duration variation method, Exoplanet catalogs, Exoplanets, Exoplanet systems, Planetary system formation, Exoplanet detection methods, Exoplanet formation
TOI-1749: an M dwarf with a Trio of Planets including a Near-resonant Pair. We report the discovery of one super-Earth- (TOI-1749b) and two sub-Neptune-sized planets (TOI-1749c and TOI-1749d) transiting an early M dwarf at a distance of 100 pc, which were first identified as planetary candidates using data from the TESS photometric survey. We have followed up this system from the ground by means of multiband transit photometry, adaptive optics imaging, and low-resolution spectroscopy, from which we have validated the planetary nature of the candidates. We find that TOI-1749b, c, and d have orbital periods of 2.39, 4.49, and 9.05 days, and radii of 1.4, 2.1, and 2.5 R⊕, respectively. We also place 95% confidence upper limits on the masses of 57, 14, and 15 M⊕ for TOI-1749b, c, and d, respectively, from transit timing variations. The periods, sizes, and tentative masses of these planets are in line with a scenario in which all three planets initially had a hydrogen envelope on top of a rocky core, and only the envelope of the innermost planet has been stripped away by photoevaporation and/or core-powered mass-loss mechanisms. These planets are similar to other planetary trios found around M dwarfs, such as TOI-175b,c,d and TOI-270b,c,d, in the sense that the outer pair has a period ratio within 1% of 2. Such a characteristic orbital configuration, in which an additional planet is located interior to a near 2:1 period-ratio pair, is relatively rare around FGK dwarfs.

Keywords: M dwarf stars, Transit duration variation method, Transits, Super Earths, Mini Neptunes, Exoplanet detection methods
On the Utility of Transmission Color Analysis I: Differentiating Super-Earths and Sub-Neptunes. The majority of exoplanets found to date have been discovered via the transit method, and transmission spectroscopy represents the primary method of studying these distant worlds. Currently, in-depth atmospheric characterization of transiting exoplanets entails the use of spectrographs on large telescopes, requiring significant observing time to study each planet. Previous studies have demonstrated trends for solar system worlds using color-color photometry of reflectance spectra, as well as trends within transmission spectra for hot Jupiters. Building on these concepts, we have investigated the use of transmission color photometric analysis for efficient, coarse categorization of exoplanets and for assessing the nature of these worlds, with a focus on resolving the bulk composition degeneracy to aid in discriminating super-Earths and sub-Neptunes. We present our methodology and first results, including spectrum models, model comparison frameworks, and wave band selection criteria. We present our results for different transmission "color" metrics, filter selection methods, and numbers of filters. Assuming noise-free spectra of isothermal atmospheres in chemical equilibrium, with our pipeline, we are able to constrain atmospheric mean molecular weight in order to distinguish between super-Earth and sub-Neptune atmospheres with &gt;90% overall accuracy using specific low-resolution filter combinations, . We also found that increasing the number of filters does not substantially impact this performance. This method could allow for broad characterization of large numbers of planets much more efficiently than current methods permit, enabling population- and system-level studies. Additionally, data collected via this method could inform follow-up observing time by large telescopes for more detailed studies of worlds of interest.

Keywords: Super Earths, Transmission spectroscopy, Atmospheric composition, Mini Neptunes, Transit photometry, Exoplanet atmospheres
L 98-59: A Benchmark System of Small Planets for Future Atmospheric Characterization. The M3V dwarf star L 98-59 hosts three small (R &lt; 1.6 R⊕) planets. The host star is bright (K = 7.1) and nearby (10.6 pc), making the system a prime target for follow-up characterization with the Hubble Space Telescope (HST) and the upcoming James Webb Space Telescope (JWST). Herein, we use simulated transmission spectroscopy to evaluate the detectability of spectral features with HST and JWST assuming diverse atmospheric scenarios (e.g., atmospheres dominated by H2, H2O, CO2, or O2). We find that H2O and CH4 present in a low mean molecular weight atmosphere could be detected with HST in one transit for the two outermost planets, while H2O in a clear steam atmosphere could be detected in six transits or fewer with HST for all three planets. We predict that observations using JWST/NIRISS would be capable of detecting a clear steam atmosphere in one transit for each planet and H2O absorption in a hazy steam atmosphere in two transits or less. In a clear, desiccated atmosphere, O2 absorption may be detectable for all three planets with NIRISS. If the L 98-59 planets possess a clear, Venus-like atmosphere, NIRSpec could detect CO2 within 26 transits for each planet, but the presence of H2SO4 clouds would significantly suppress CO2 absorption. The L 98-59 system is an excellent laboratory for comparative planetary studies of transiting multiplanet systems, and observations of the system via HST and JWST would present a unique opportunity to test the accuracy of the models presented in this study.

Keywords: Extrasolar rocky planets, Astronomy data modeling, Exoplanets, Transmission spectroscopy, Low mass stars, Exoplanet atmospheres, Near infrared astronomy
TESS Data for Asteroseismology: Photometry. Over the last two decades, asteroseismology has increasingly proven to be the observational tool of choice for the study of stellar physics, aided by the high quality of data available from space-based missions such as CoRoT, Kepler, K2, and the Transiting Exoplanet Survey Satellite (TESS). TESS in particular will produce more than an order of magnitude more such data than has ever been available before. While the standard TESS mission products include light curves from 120 s observations suitable for both exoplanet and asteroseismic studies, they do not include light curves for the vastly larger number of targets observed by the mission at a longer 1800 s cadence in Full Frame Images (FFIs). To address this lack, the TESS Data for Asteroseismology (T'DA) group under the TESS Asteroseismic Science Consortium (TASC) has constructed an open-source pipeline focused on producing light curves for all stars observed by TESS at all cadences, currently including stars down to a TESS magnitude of 15. The pipeline includes target identification, background estimation and removal, correction of FFI time stamps, and a range of potential photometric extraction methodologies, though aperture photometry is currently the default approach. For the brightest targets, we transparently apply a halo photometry algorithm to construct a calibrated light curve from unsaturated pixels in the image. In this paper, we describe in detail the algorithms, functionality, and products of this pipeline and summarize the noise metrics for the light curves. Companion papers will address the removal of systematic noise sources from our light curves, and a stellar variability classification from these.

Keywords: CCD photometry, Asteroseismology, Astronomy data analysis, Variable stars
Extended Tidal Tails of IC 4756 Detected by Gaia EDR3. We report the discovery of emerged tidal tails around open cluster IC 4756 (~1 Gyr) based on 644 members identified from Gaia EDR3. Three-dimensional spatial positions and two-dimensional tangential velocities $\left(x,y,z,\kappa \cdot {\mu }_{\alpha }^{* }/\varpi ,\kappa \cdot {\mu }_{\delta }/\varpi \right)$ are utilized to determine the comoving member candidates of IC 4756. Using a Bayesian method, we correct the distance for each cluster member. Two tidal tails extend up to 180 pc and display an S shape in the $X^{\prime} Y^{\prime} $ space (Cartesian coordinates focused on cluster center). A clean sequence of our members in the color-absolute-magnitude diagram indicates the coeval population and matches perfectly with the PARSEC isochrone with age from Bossini et al. Mass segregation is detected in this cluster as well. Finally, we derive the tidal radius and core radius of IC 4756 about 12.13 pc and 4.33 ± 0.75 pc, respectively.

Keywords: Stellar kinematics, Open star clusters
A More Precise Mass for GJ 1214 b and the Frequency of Multiplanet Systems Around Mid-M Dwarfs. We present an intensive effort to refine the mass and orbit of the enveloped terrestrial planet GJ 1214 b using 165 radial velocity (RV) measurements taken with the HARPS spectrograph over a period of 10 years. We conduct a joint analysis of the RVs with archival Spitzer/IRAC transits and measure a planetary mass and radius of 8.17 ± 0.43 M⊕ and ${2.742}_{-0.053}^{+0.050}$ R⊕. Assuming that GJ 1214 b is an Earth-like core surrounded by a H/He envelope, we measure an envelope mass fraction of Xenv = ${5.24}_{-0.29}^{+0.30}$ %. GJ 1214 b remains a prime target for secondary eclipse observations of an enveloped terrestrial, the scheduling of which benefits from our constraint on the orbital eccentricity of &lt;0.063 at 95% confidence, which narrows the secondary eclipse window to 2.8 hr. By combining GJ 1214 with other mid-M-dwarf transiting systems with intensive RV follow up, we calculate the frequency of mid-M-dwarf planetary systems with multiple small planets and find that ${90}_{-21}^{+5}$ % of mid-M dwarfs with a known planet with mass ∈ [1, 10] M⊕ and orbital period ∈ [0.5, 50] days, will host at least one additional planet. We rule out additional planets around GJ 1214 down to 3 M⊕ within 10 days, such that GJ 1214 is a single-planet system within these limits. This result has a ${44}_{-5}^{+9}$ probability given the prevalence of multiplanet systems around mid-M dwarfs. We also investigate mid-M-dwarf RV systems and show that the probability that all reported RV planet candidates are real planets is &lt;12% at 99% confidence, although this statistical argument is unable to identify the probable false positives.

Keywords: M dwarf stars, Transits, Exoplanets, Exoplanet structure, Radial velocity
Multiple Mg II Absorption Systems in the Lines of Sight to Quadruply Lensed Quasar H1413+1143. We find multiple Mg II absorption systems at redshift z = 1.66, 2.069, and 2.097 in the spatially resolved spectra of the quadruply gravitationally lensed quasar H1413+1143 utilizing the Kyoto tridimensional spectrograph II (Kyoto 3D II) spectrograph on board the Subaru telescope. Here we present the first measurement of differences in Mg II absorption strength of the multiple intervening absorbers, which include ones identified as damped Lyα (DLA) absorption systems. Our detection of the significant Mg II absorptions in the spatially resolved spectra reveals the inhomogeneous chemical enrichment on scales of about 12 kpc within the separation of the four sight lines. For the DLA system at z = 1.66, the rest equivalent widths (EWs) of the Mg II absorption lines between the four spatially resolved lines of sight change by factors of up to ~6, which trace the variations in the H I absorption strength. This suggests that inhomogeneous cold absorbers that give rise to the strong H I/Mg II absorptions dwell on a scale of about 6-12 kpc between the four lines of sight. We also investigate the degree of variation in the EW of the absorption lines between the lines of sight. We find that the systems giving rise to strong absorptions in the spectra of the quadruply lensed quasars tend to have a high degree of variation in absorption strength between the lines of sight toward the lensed quasars.

Keywords: Intergalactic medium, Quasar absorption line spectroscopy, Galactic and extragalactic astronomy
The Solar Neighborhood XLVIII: Nine Giant Planets Orbiting Nearby K Dwarfs, and the CHIRON Spectrograph's Radial Velocity Performance. We report initial results of a large radial velocity survey of K dwarfs up to a distance of 50 pc from the solar system, to look for stellar, brown dwarf, and Jovian planets using radial velocities from the CHIRON spectrograph on the CTIO/SMARTS 1.5 m telescope. We identify three new exoplanet candidates orbiting host stars in the K dwarf survey and confirm a hot Jupiter from TESS orbiting TOI 129. Our techniques are confirmed via five additional known exoplanet orbiting K dwarfs, bringing the number of orbital solutions presented here to 9, each hosting an exoplanet candidate with a minimum mass of 0.5-3.0 MJup. In addition, we provide a list of 186 nearby K dwarfs with no detected close companions that are ideal for more sensitive searches for lower-mass planets. This set of stars is used to determine CHIRON's efficiency, stability, and performance for radial velocity work. For K dwarfs with V = 7-12, we reach radial velocity precisions of 5-20 ms-1 under a wide range of observing conditions. We demonstrate the stability of CHIRON over hours, weeks, and years using radial velocity standards, and describe instrumental capabilities and operation modes available for potential users.

Keywords: Surveys, Solar neighborhood, Astronomical techniques, Radial velocity, Extrasolar gaseous giant planets
Optical Spectroscopic Observations of Gamma-ray Blazar Candidates. XI. Optical Observations from SOAR, Blanco, NTT and OAN-SPM. The Story So Far. Blazars represent about 62% of the sources in the γ-ray Fermi-LAT catalog, and about 80% of the γ-ray sources associated with a lower-energy counterpart, dominating the γ-ray sky. In particular, about 42% of the γ-ray blazars are classified as Blazars Candidates of Uncertain type (BCUs) for which spectroscopic observations are mandatory to confirm their blazar nature. Here we report the spectra of 64 targets observed as part of our follow-up optical spectroscopic campaign. This sample includes 62 sources classified in Fermi-LAT catalog as BCUs, one source classified as a generic active galactic nucleus, and one source classified as a BL Lac in Fermi-LAT and as blazar of uncertain type in the Roma-BZCAT catalog. We confirm the blazar nature of all BCUs. We classify 33 of them as BL Lacs, 11 as Flat Spectrum Radio Quasars, and 18 as blazars with nonnegligible host-galaxy emission. We also classify the generic active galactic nucleus as a BL Lac. Finally, we confirm the classification of the BL Lac. We also reported a lower limit redshift for 43 sources. For 20 sources, we got redshift measurements consistent with the literature values. For the other 21 sources, we obtained their first spectroscopic redshift measurement; while, for two sources, we provide lower limits on the redshift. With the upcoming release of the sixth edition of the Roma-BZCAT Multifrequency Catalog of Blazars, we take the opportunity in the present work to present the collective results of the first phase of our optical spectroscopic follow-up campaign.

Keywords: Optical identification, Flat-spectrum radio quasars, BL Lacertae objects, Blazars
The Extraordinary Passage of Comet C/2020 F3 NEOWISE: Evidence for Heterogeneous Chemical Inventory in Its Nucleus. Upon its discovery in 2020 March, we requested Director Discretionary Time (DDT) at the NASA/IRTF facility to observe comet C/2020 F3 (NEOWISE), with the high-resolution spectrograph iSHELL. The comet approached the Sun, down to 0.3 au, in early 2020 July, providing a spectacular perihelion passage and revealing itself as one of the brightest comets that have appeared in the northern hemisphere in recent decades. Daytime observations with iSHELL/IRTF were performed to study the comet immediately after its perihelion passage, from 9 July to 1 August. In early August, a DDT at Keck Observatory was requested to continue following the comet with NIRSPEC 2.0. We acquired comprehensive high-resolution spectra of the comet as it progressively retreated from perihelion. We detected many cometary emission lines in the (2.8-5.3) μm range, identifying 12 molecular species: 9 primary volatiles (H2O, HCN, NH3, CO, C2H2, C2H6, CH4, CH3OH, and H2CO) and 3 product species (CN, NH2, OH). In this paper, we present the analysis and discussion of the molecular abundances found in this comet, and we compare them to reference median values for Oort Cloud Comets. Measured molecular mixing ratios showed drastic changes during our observing campaign, which spanned nearly one month from 2020 July 9 to August 6. Here, we provide a detailed discussion of the molecular spatial distributions and their role in identifying the presence of extended sources in the coma. Our investigations provided evidence for the heterogeneous chemical composition of the comet's nucleus.

Keywords: High resolution spectroscopy, Astrobiology, Comet volatiles