Sazuna/UAT_keywords huggingface dataset:
L-band Calibration of the Green Bank Telescope from 2016-2019. Since 2016, the HI-MaNGA survey has been obtaining neutral hydrogen (which emits a radio 21cm line) measurements for nearby galaxies which are part of a survey known as "MaNGA". This has been done using observations at the Green Bank Radio Telescope (GBT). We use calibration data obtained routinely at the start of observing runs during this entire period, as well as an extra set of calibration data obtained in 2019 to check the standard GBT data reduction calibrations at L-band (1.4 GHz, or 20cm). We find an constant offset of 20% in the calibration relative to the standard values given in the GBT data reduction pipeline for data of this type. This correction will be used to improve measurements for HI-MaNGA.

Keywords: Surveys, H I line emission, Radio telescopes, Flux calibration
The Diffuse Supernova Neutrino Background. The Diffuse Supernova Neutrino Background (DSNB) in the MeV regime represents the cumulative cosmic neutrino emission, predominantly due to core collapse supernovae. We estimate the DSNB flux for different Star Formation Rate Density (SFRD) models. We find that the DSNB flux estimated using the SFRD derived from Fermi-LAT Collaboration et al. (2018) is significantly higher ($\approx$ 32$\%$) relative to the flux estimated using the SFRD from Madau &amp; Fragos (2017). This depicts the sensitivity between the DSNB flux and the SFRD estimates which shows that future detection of the DSNB can be used as a valuable tool to constrain the SFRD.

Keywords: Diffuse radiation, Type II supernovae, Supernova neutrinos
A Catalog of Galactic Multiple Systems with a Red Supergiant and a B Star. Binary systems composed of a red supergiant and a B star are useful probes of stellar evolution. We have searched the literature to create a catalog of 108 Galactic systems of such type, which is presented here.

Keywords: Early-type stars, B stars, Late-type stars, Binary stars, Red supergiant stars, Late-type supergiant stars, Catalogs
Gravitational Microlensing Events from the First Year of the Northern Galactic Plane Survey by the Zwicky Transient Facility. The Zwicky Transient Facility (ZTF) is currently surveying the entire northern sky, including dense Galactic plane fields. Here, we present preliminary results of the search for gravitational microlensing events in the ZTF data collected from the beginning of the survey (March 20, 2018) through June 30, 2019.

Keywords: Gravitational microlensing
Extended Self-similar Solution for Circumstellar Material-supernova Ejecta Interaction. In this note, we present a detailed self-similar solution to the interaction of a uniformly expanding gas and a stationary ambient medium, with an application to supernovae interacting with preexisting circumstellar media (Type IIn SNe). We implement the generalized solution into the Modular Open Source Fitter for Transients (MOSFiT), an open-source Python package for fitting extragalactic transient light curves.

Keywords: Light curves, Circumstellar shells, Supernovae
TESS Extended Mission 10 Minute Cadence Retains Nyquist Aliases. During its two-year prime mission, the Transiting Exoplanet Survey Satellite (TESS) is obtaining full-frame images with a regular 30-minute cadence in a sequence of 26 sectors that cover a combined 85% of the sky. While its primary science case is to discover new exoplanets transiting nearby stars, TESS data are superb for studying many types of stellar variability, with the number of publications using TESS data for other areas of astrophysics keeping pace with exoplanet papers. Following the conclusion of its prime mission in July 2020, TESS will revisit the sky in an extended mission that records full-frame images at a faster ten-minute cadence. In this note, I demonstrate that choosing a large submultiple of the original exposure times for the new cadence limits the synergy between prime and extended TESS mission data since both sampling rates produce many of the same Nyquist aliases. Adjusting the extended mission exposure time by as little as one second would largely resolve Nyquist ambiguities in the combined TESS data set.

Keywords: Astronomical techniques, Variable stars, Time series analysis, Astrostatistics strategies
VMC J021140.41-735320.4—An Extremely Red L Dwarf Candidate Member of the AB Doradus Young Moving Group. We report the discovery of VMC J021140.41-735320.4, a faint ($J=19.9$ mag) and extremely red ($J-K_s=3.0$ mag, $W1-W2=0.45$ mag, $J-W2=4.7$ mag) high proper motion object in front of the Magellanic Bridge region. It is even redder in the near-infrared than the reddest L7 dwarfs ($J-K_s \gtrsim 2.8$ mag) found in the survey of Schneider et al. (2017) and its colours do also not match exactly those of other peculiar red L7.5 dwarfs. Therefore, we consider its photometric distance estimate of about 73 pc as uncertain. A preliminary combined proper motion and parallax solution involving 20 epochs from the Visible and Infrared Survey Telescope for Astronomy (VISTA) survey of the Magellanic Clouds (VMC), the VISTA hemisphere survey (VHS), and the Wide-field Infrared Survey Explorer (WISE) yields $\mu_{\alpha}\cos{\delta}=+74.3\pm3.4$ mas/yr, $\mu_{\delta}=+22.3\pm3.4$ mas/yr, and $\pi=21.0\pm7.1$ mas. Applying the BANYAN tool (http://www.exoplanetes.umontreal.ca/banyan/) to these results we find a $\approx$68% membership probability of this object in the AB Doradus young moving group (YMG). With its trignometric distance of $\approx$48 pc, VMC J021140.41-735320.4 has a similar absolute magnitude of $M_{K_s}\approx13.4$ mag as the planetary mass companion of another AB Doradus YMG member candidate, 2MASS J22362452+4751425. Follow-up classification spectroscopy and astrometric monitoring are recommended.

Keywords: Brown dwarfs, Proper motions
Potential Backup Targets for Comet Interceptor. Comet Interceptor is an ESA F-class mission expected to launch in 2028 on the same launcher as ESA's ARIEL mission. Comet Interceptor's science payload consists of three spacecraft, a primary spacecraft that will carry two smaller probes to be released at the target. The three spacecraft will fly-by the target along different chords, providing multiple simultaneous perspectives of the comet nucleus and its environment. Each of the spacecraft will be equipped with different but complementary instrument suites designed to study the far and near coma environment and surface of a comet or interstellar object (ISO). The primary spacecraft will perform a fly-by at ~1000 km from the target. The two smaller probes will travel deeper into the coma, closer to the nucleus. The mission is being designed and launched without a specific comet designated as its main target. Comet Interceptor will travel to the Sun-Earth L2 Lagrangian point with ARIEL and wait in hibernation until a suitable long-period comet (LPC) is found that will come close enough to the Sun for the spacecraft to maneuver to an encounter trajectory. To prepare for all eventualities, the science team has assembled a preliminary set of backup targets from the known Jupiter family comets, where a suitable fly-by trajectory can be achieved during the nominal mission timeline (including the possibility of some launch delay). To better prioritize this list, we are releasing our potential backup targets in order to solicit the planetary community's help with observations of these objects over future apparitions and to encourage publication of archival data on these objects.

Keywords: Antarctic observatories, Comets, Short period comets, Small Solar System bodies
An Updated Galactic Double Neutron Star Merger Rate Based on Radio Pulsar Populations. Following the procedure described in Pol et al., we update the Galactic double neutron star (DNS) merger rate by including the new, highly eccentric DNS system J0509+3801 (Lynch et al.). This leads to a new Galactic DNS merger rate of $\mathcal{R}_{\rm MW} = 37^{+24}_{-11}$ Myr$^{-1}$, where the errors represent 90% confidence intervals. The corresponding DNS merger detection rate for Advanced LIGO is $\mathcal{R} = 1.9^{+1.2}_{-0.6} \times \left( D_{\rm r} / 100 \ \rm Mpc \right)^3 \rm yr^{-1},$ where $D_{\rm r}$ is the range distance. Using the LIGO O3 range distance of 130 Mpc (Abbott et al.), we predict that LIGO will detect anywhere between three and seven DNS mergers per year of observing at O3 sensitivity.

Keywords: Millisecond pulsars, Gravitational wave sources, Pulsars, Gravitational wave astronomy, Binary pulsars, Radio pulsars
A New Orbital Ephemeris for WASP-128b. WASP-128 is a relatively bright (V= 12.37) G0-dwarf, known to host a transiting brown dwarf in a short-period orbit (Hodžić et al. 2018 arXiv:1807.07557 (H18)). Very few such objects are known, which makes WASP-128 a prime target for further observations to better understand giant planet / brown dwarf properties,including formation and migration histories. To facilitate the planning of future observations of WASP-128b, we improve the orbital ephemeris of the system, by using the seven transits of WASP-128 observed by TESS. We note that our orbital period differs significantly from that of H18: it is more than $14\,\sigma$ (using their uncertainty) larger. This results in our ephemeris predicting a mid-2020 transit to occur almost eight hours later than the H18 ephemeris. We find, however, no evidence for any period variation.

Keywords: Ephemerides, Brown dwarfs, Exoplanets
Outer Planet Single-transit Detections with LSST. In our solar system massive outer planets dominate in terms of both mass and angular momentum, but few such planets are among the more than 4000 currently confirmed exoplanets, and none of these have accurately determined densities. Here I examine the detection rate of single-transit events anticipated from the LSST deep drilling fields for such planets with periods of 2 - 25 years. Using conservative detection criteria, I anticipate 3-30 such detections over the 10-year period of the project, though distinguishing detections from false positives may prove challenging. However, these few detections are likely to be of great value in understanding the formation, dynamics, and diversity of exoplanet systems.

Keywords: Exoplanet detection methods, Transit photometry, Sky surveys, Exoplanets
HD 196390: A Tight Correlation of Differential Abundances with Condensation Temperature. Bedell et al. (2018) give precision differential abundances for 79 mostly G-dwarf stars. We correct these abundances for Galactic chemical evolution in a manner similar to that used by these authors but with parameters derived from linear fits to plots of [El/H] vs. age in lieu of [El/Fe]. We examine the resulting abundances for correlations with the 50% condensation temperature using values from both Lodders (2003) and Wood et al. (2019), and compare with the results of Bedell et al. HD 196390 is distinct in having the most significant correlation of the 79-star sample. We report statistics for a subset of stars with lower significance, but of some interest.

Keywords: Solar abundances, Stellar astronomy, Stellar physics, Solar physics
Arcminute MicroKelvin Imager observations at 15 GHz of the 2020 February Outburst of Cygnus X-3. Here we report observations of a recent giant radio flare from Cygnus X-3 in 2020 February, made with the Arcminute MicroKelvin Imager.

Keywords: Galactic radio sources, High mass x-ray binary stars, Variable radiation sources, Radio continuum emission
No Radio Bursts Detected from FIRST J141918.9+394036 in Green Bank Telescope Observations. FRB 121102, the first-known repeating fast radio burst (FRB) source, is associated with a dwarf host galaxy and compact, persistent radio source. In an effort to find other repeating FRBs, FIRST J141918.9+394036 (hereafter FIRST J1419+3940) was identified in a search for similar persistent radio sources in dwarf host galaxies. FIRST J1419+3940 was subsequently identified as a radio transient decaying on timescales of decades, and it has been argued that it is the orphan afterglow of a long gamma-ray burst. FIRST J1419+3940 and FRB 121102's persistent radio source show observational similarities, though the latter appears to be stable in brightness. Nonetheless, if they have similar physical origins, then FIRST J1419+3940 may also contain a source capable of producing fast radio bursts. We report the non-detection of short-duration radio bursts from FIRST J1419+3940 during 3.1 h of observations with the 110-m Green Bank Telescope at both 2 and 6 GHz. FIRST J1419+3940 is 11 times closer compared with FRB 121102, and exhibits an optically-thin synchrotron spectrum above 1.4GHz; our search was thus sensitive to bursts more than 100 times weaker than those seen from FRB 121102. We encourage future burst searches to constrain the possible presence of an FRB-emitting source. Although such searches are high-risk, any such detection could greatly elucidate the origins of the FRB phenomenon.

Keywords: Gamma-ray bursts, Transient sources, Radio bursts, Radio sources, Radio transient sources
Gaia DR2 Color-Temperature Relations Based on Infrared Flux Method Results. The ESA/Gaia mission is providing accurate and precise all-sky photometry. We combined effective temperatures derived, for a sample of dwarf and giant stars, by Gonzalez Hernandez \&amp; Bonifacio (2009) using the Infrared Flux Method, with the photometry available from the second release of the ESA/Gaia mission. We provide colour-temperature relations for the broad-band colours (BP-RP), (BP-G), (G-RP), (G-K), (BP-K), (RP-K). These relations allow the exploitation of the all-sky Gaia DR2 photometry to obtain precise effective temperatures.

Keywords: Stellar effective temperatures, Stellar atmospheres
No Consistent Atmospheric Absorption Detected for the Ultra-hot Jupiter WASP-189 b. We observed a partial transit of the ultra-hot Jupiter WASP-189 b with PEPSI on the LBT. We detect a highly variable transit signal in multiple atomic transitions, including H-alpha, Fe I, and Mg I. The signal is not consistent with a transiting planetary atmosphere. We suggest instead that the in-transit signal is due to an inhomogeneous stellar surface. Our observations demonstrate the lack of a highly extended atmosphere in common optical atomic tracers. Although WASP-189 is very bright, atmospheric characterization of the planet will be difficult due to the small transit depth and apparently compact atmosphere.

Keywords: Exoplanet astronomy, Exoplanet atmospheres
The Parallax of VHS J1256-1257 from CFHT and Pan-STARRS-1. We present new parallax measurements from the CFHT Infrared Parallax Program and the Pan-STARRS 3$\pi$ Steradian Survey for the young ($\approx150-300$ Myr) triple system VHS J125601.92$-$125723.9. This system is composed of a nearly equal-flux binary ("AB") and a wide, possibly planetary-mass companion ("b"). The system's published parallactic distance ($12.7\pm1.0$ pc) implies absolute magnitudes unusually faint compared to known young objects and is in tension with the spectrophotometric distance for the central binary ($17.2\pm2.6$ pc). Our CFHT and Pan-STARRS parallaxes are consistent, and the more precise CFHT result places VHS J1256-1257 at $22.2^{+1.1}_{-1.2}$ pc. Our new distance results in higher values for the companion's mass ($19\pm5$ M$_{\rm Jup}$) and temperature ($1240\pm50$ K), and also brings the absolute magnitudes of all three components into better agreement with known young objects.

Keywords: Brown dwarfs
The Search for MeV Electrons 2-45 au from the Sun with the Alice Instrument Microchannel Plate Detector on board New Horizons. The Alice UV spectrograph aboard NASA's New Horizons mission is sensitive to MeV electrons that penetrate the instrument's thin aluminum housing and interact with its microchannel plate detector. We have searched for penetrating electrons at heliocentric distance of 2-45 au, finding no evidence of discrete events outside of the Jovian magnetosphere. However, we do find a gradual long-term increase in the Alice instrument's global dark count rate at a rate of ∼1.5% per year, which may be caused by a heightened gamma-ray background from aging of the spacecraft's radioisotope thermoelectric generator fuel. If this hypothesis is correct, then the Alice instrument's global dark count rate should flatten and then decrease over the next 5-10 years.

Keywords: Interplanetary medium, Solar system
Prospects for the In Situ detection of Comet C/2019 Y4 ATLAS by Solar Orbiter. The European Space Agency's Solar Orbiter spacecraft will pass approximately downstream of the position of comet C/2019 Y4 (ATLAS) in late May and early June 2020. We predict that the spacecraft may encounter the comet's ion tail around 2020 May 31—June 1, and that the comet's dust tail may be crossed on 2020 June 6. We outline the solar wind features and dust grain collisions that the spacecraft's instruments may detect when crossing the comet's two tails. Solar Orbiter will also pass close to the orbital path of C/2020 F8 (SWAN) on 2020 May 22, but we believe that it is unlikely to detect any material associated with that comet.

Keywords: Space probes, Comet tails, Solar wind, Ionized coma gases, Interplanetary dust, Coma dust
A Population-Informed Mass Estimate for Pulsar J0740+6620. Galactic double neutron star systems have a tight mass distribution around ∼1.35M⊙, but the mass distribution of all known pulsars is broader (Tauris et al. 2017). Here we reconstruct the Alsing et al. (2018), Antoniadis et al. (2016) bimodal mass distribution of pulsars observed in binary systems, incorporating data from observations of J0740+6620 which were not available at the time of those works. Because J0740+6620 is an outlier in the mass distribution with non-negligible uncertainty in its mass measurement, its mass receives a large correction from the population, becoming ${m}_{{\rm{J}}0740+6620}={2.03}_{-0.08}^{+0.10}\,{M}_{\odot }$ (median and 68% CI). Stochastic samples from our population model, including population-informed pulsar mass estimates, are available at https://github.com/farr/AlsingNSMassReplication and archived at Farr &amp; Chatziioannou (2020).

Keywords: Neutron stars
A Common Proper-motion Companion to the Herbig Be Star HD 259431. We report on new measurements with the SPHERE instrument on the VLT of a companion 3"117 N (PA = 345°3) of the Herbig Be star HD 259431 (MWC 147). Comparison with previous literature measurements shows the companion to have a common proper motion with HD 259431. It is likely a 1.2 M⊙ young star surrounded by a disk.

Keywords: Herbig Ae/Be stars, Emission line stars, Infrared excess, Coronagraphic imaging, Pre-main sequence stars, Star formation, Protoplanetary disks, Astrometry
WISE J135501.90-825838.9 is a Nearby, Young, Extremely Low-mass Substellar Binary. We present a parallax solution for WISE J135501.90-825838.9, a spectral binary with spectral types L7+T7.5 and a candidate AB Doradus member. Using Wide-field Infrared Survey Explorer (WISE) astrometry, we obtain a distance of d = 16.7 ± 5.3 pc. This preliminary parallax solution provides further evidence that WISE J135501.90-825838.9 is a member of AB Doradus (130-200 Myr), and when combined with evolutionary models predicts masses of 11 MJup and 9 MJup for each component.

Keywords: Trigonometric parallax, Brown dwarfs, Binary stars, Parallax, Close binary stars, Astrometry, Low mass stars
X-Ray Emission from GW170817 ∼2.5 years After the Merger. The binary neutron star merger GW170817 is the first and only astronomical object with a joint detection of gravitational waves and electromagnetic radiation. Here we report the results from deep Chandra X-ray observations of GW170817 at δt ∼ 940 days post merger. We find evidence for X-ray emission with flux Fx = $({2.24}_{+0.97}^{-0.96})\times {10}^{-15}\,\mathrm{erg}\,{\mathrm{cm}}^{-2}\,{{\rm{s}}}^{-1}$ (Lx = ${4.29}_{+1.86}^{-1.84}\times {10}^{38}\,\mathrm{erg}\,{{\rm{s}}}^{-1}$ , 0.3-10 keV). This flux is consistent with the expected late-time evolution of non-thermal emission from an off-axis structured jet and it is now approaching the sensitivity threshold of current X-ray instrumentation. Future observations might reveal the emergence of the kilonova afterglow.

Keywords: Neutron stars, Gravitational waves
The Outburst of Centaur 29P/Schwassmann-Wachmann on 2020 February 4th. We observed the 2020 February 4th outburst of the Centaur 29P/Schwassmann-Wachmann, using the James Gregory Telescope in St Andrews/UK. The brightness of the comet increased by ∼3 mag in VRI within 1-2 days, followed by a more gradual incline. This was one of the largest documented outbursts of this object over the past few years, but is consistent with previously observed events.

Keywords: Small Solar System bodies, Comets, Centaur group, CCD photometry
Empirical Relationship between Calcium Triplet Equivalent Widths and [Fe/H] Using Gaia Photometry. I present a new empirical calibration, using Gaia photometry, of the relationship between the metallicity of red giant branch (RGB) stars and the equivalent widths of their Ca II triplet lines. The equivalent widths are taken from a spectral library of 2050 RGB stars from 18 globular clusters observed with the Anglo-Australian Telescope's AAOmega spectrograph between 2006 and 2017. The stars cover a metallicity range of $-0.49\gt [\mathrm{Fe}/{\rm{H}}]\gt -2.27$ .

Keywords: Globular star clusters, Stellar abundances
Limits on Vibrationally Excited HCN Emission in Four HCN-enhanced GOALS Galaxies. Vibrationally excited HCN emission can be used to identify luminous, optically obscured active galactic nucleus. We report Band 7 ALMA observations of four HCN-enhanced GOALS galaxies and derive upper limits to their vibrationally excited HCN emission. These upper limits and the lack of self-absorbed HCO+ line profiles imply that luminous, optically obscured energy sources are not present in this sample of systems.

Keywords: Molecular gas, Active galactic nuclei, Starburst galaxies, Luminous infrared galaxies
Inconsistency of the R<SUB>h</SUB> = ct Cosmology from the Viewpoint of the Redshift of the Cosmic Microwave Background Radiation. The redshift of the cosmic microwave background (CMB) radiation in the Rh = ct cosmology (Melia &amp; Shevchuk 2012) is inferred from nearly model-independent measurements of the angular baryon acoustic oscillations and the first acoustic peak location of the CMB power spectrum, based on the assumption that the two phenomena occur at the same comoving scale in the Rh = ct model (Melia &amp; López-Corredoira 2017). The derived redshift, z* ≈ 23, which corresponds to the radiation temperature T* ≈ 65 K, is inconsistent with the standard interpretation of the CMB as the relic radiation of the Big Bang.

Keywords: Cosmological models, Cosmic microwave background radiation, Expanding universe, Friedmann universe, Baryon acoustic oscillations
Photometric Variability of T Tauri S as a Probe for Circumstellar Material. The irregular photometric variability of the triple system T Tauri has been puzzling since its discovery. A circumbinary disk around T Tau Sa and Sb can explain the recent brightness fluctuations of T Tau Sb, due to changes in extinction depending on the position of T Tau Sb in its orbit. The photometric variations and orbital motion of T Tau Sb indicate a position angle of the disk of ∼30°. Combined with information from the literature, we estimate its inclination to be ∼60° or more.

Keywords: Trinary stars, Young stellar objects, Circumstellar matter, Classical T Tauri stars
An Extremely Temporary Co-orbital: The Dynamical State of Active Centaur 2019 LD2. We investigate the recent and future orbital evolution of the solar system small body 2019 LD2 (hereafter "LD2"), which was recently found to show cometary activity. While LD2's orbit initially looks similar to that of a Jupiter Trojan, numerical integrations show that it is only co-orbital with Jupiter for approximately a single orbit around the Sun. This would classify LD2 as an active Centaur, but we stress this object remains unique; within the next ∼40-50 years LD2 is likely to become a Jupiter Family Comet, offering an opportunity to observe this critical transition.

Keywords: Orbits, Centaur group, Jupiter trojans