Sazuna/UAT_keywords huggingface dataset:
ASKAP-EMU Discovery of New Galactic SNR Candidate: Unicycle (G312.65+2.87). We present the serendipitous discovery of a low surface brightness Galactic supernova remnant candidate, Unicycle (G312.65+2.87). Unicycle was initially discovered in the Evolutionary Map of the Universe large-scale radio survey at 943.5 MHz. We measure a diffuse shell (D = 288″ × 300″) and an integrated flux density of S I 944 MHz = 150 ± 20 mJy. We estimate the most likely intrinsic diameters of 30 &lt; D &lt; 36 pc or 42 &lt; D &lt; 47 pc, corresponding to distances of 10 &lt; d &lt; 12 kpc or 14 &lt; d &lt; 16 kpc, placing it within either the Scutum–Centaurus or outer Sagittarius spiral arms.

Keywords: Supernova remnants, Milky Way Galaxy, Radio continuum emission
Discovery of the Blazhko-type Effect in the HADS Star V965 Cep. We derived additional pulsation frequencies in the HADS star V965 Cep from the frequency analysis of the O ‑ C diagram built with the TESS Quick-Look Pipeline (QLP) data and from the TESS QLP light curve. Thus, the star appeared to be a multi-mode pulsator with a modulated light curve, similar to RR Stars with the Blazhko effect.

Keywords: Delta Scuti variable stars, Astronomy data analysis, Blazhko effect
Hidden Companions to Intermediate-mass Stars. XX. Discovery of a 0.58M <SUB>⊙</SUB>, 7.4 au Companion to p Puppis. p Puppis is a nearby 3.1M ⊙ B8V star with astrometric evidence for a close companion in addition to its two wide companions at 1.3 kau (a white dwarf (WD)) and 38.7 kau (an F2V astrometric binary). Here we report on a VLTI/GRAVITY observation that revealed the close companion to be a 0.58M ⊙ star at a projected separation ρ = 100.2 mas ↔ 7.4 au, confirming the system to be a quintuple. The discovered companion explains the X-ray emission of p Pup detected by eROSITA. Moreover, we also find that the isochrone age of Myr of p Pup is incompatible with the minimum cooling age of 350 Myr for the 1.3 kau wide WD companion, suggesting that either they are not coeval or that the WD was formed through a non-trivial channel. *Based on observations collected at the European Southern Observatory, Chile, Program ID 112.25QQ.001.

Keywords: Optical interferometry, Multiple stars, B stars, Wide binary stars
Disproving the High-eccentricity Planet HD 220773b. HD 220773 has been announced to host a giant planet in an eccentric orbit. Global Architecture of Planetary Systems collaboration followed this target up with the HARPS-N spectrograph at Telescopio Nazionale Galileo, in order to search for additional small planets in the system. This radial velocity monitoring produced approximately 130 HARPS-N data points, leading to the refutation of the announced planet.

Keywords: Exoplanet astronomy, Exoplanet detection methods, Radial velocity
Do We Finally Know all Stellar and Substellar Neighbors within 10 pc of the Sun?. Our knowledge on the closest solar neighbors gradually improved over a long time with the help of new methods and the recognition of new stellar and substellar species. The latest burst of discoveries since 1997, in which the first author participated, seemingly filled the gap of missing systems within 10 pc from the Sun. However, previous estimates of the population relied on two assumptions: that the sample was complete within 5 pc and that the density was uniform out to 10 pc. The first of these is not true, and the second in question. Otherwise, up to about 90 systems could be still missing within 10 pc. We find no indication for missing brown dwarfs within 10 pc, but strongly increasing deficits from early-M to late-M dwarfs hint at some still hidden late-M dwarf neighbors. They may have already been detected by Gaia but published so far without or with incorrect parallax measurements, because of close companions or their location in the Galactic plane.

Keywords: Luminosity function, Brown dwarfs, Parallax, Late-type stars, Solar neighborhood, Proper motions
Observations of the 2024 May 14 X8.7 Solar Flare with the Goldstone-Apple Valley Radio Telescope (GAVRT). The Goldstone-Apple Valley Radio Telescope (GAVRT) project conducts a regular monitoring program of the Sun. The GAVRT Solar Patrol project uses a 34 m diameter antenna to produce raster-scan maps of the Sun simultaneously at 4 frequencies ranging from approximately 3 to 14 GHz. On 2024 May 14, as part of regular GAVRT Solar Patrol observations, raster maps were produced when an X8.7 solar flare occurred in active region AR13664. Here we present the GAVRT maps of the May 14 flare along with microwave flux density spectra showing the non-thermal microwave burst emission from mildly relativistic electrons produced in this largest flare of Solar Cycle 25 to date. AR13664 reappeared as AR13697 and continued to be very active, producing X flares while GAVRT monitored its activity. GAVRT microwave data provide a powerful complement to the energetic electrons tracked by X-ray, millimeter-wave and γ-ray emissions.

Keywords: Solar radio flares
A Comment on the Solar Activity Level in 1791 by Lorenzo Hervás y Panduro. Past solar activity is of great interest for astrophysical and geophysical studies. Systematic searches over the last four centuries have detailed the evolution of the solar cycle. Brief comments on solar activity for periods with sparse records, such as the year 1791, are crucial. Lorenzo Hervás y Panduro, a Jesuit intellectual, noted in his 1793 book that sunspots were seen almost daily from 1791 January 1 to April 20. This would suggest a solar activity level estimated at a sunspot number of around 70.

Keywords: Solar activity
Absorption in the Spectrum of a Background AGN by C II* by the Supernova Remnant G354-33. A number of very large, very faint supernova remnants (SNRs) have been discovered in the past few years. Those in the Galactic halo occur in low density gas, so they might be more easily observed in absorption than in emission. The SNR G354-33 is a shell of faint UV and optical filaments about 10° in diameter. Here we point out that a spectrum of the QSO J2017-4516 used study the galaxy cluster J2016-4517 shows an absorption line from the excited fine structure level of C II at ‑50 km s‑1. Absorption features of Si II and Si III are also seen at this velocity. The observed column density compares well with shock wave models. Doppler shifted C II* absorption features provide an excellent means to find and characterize SNR shocks because they arise from compressed gas.

Keywords: Supernova remnants, Interstellar line absorption, Shocks
Gnuastro: Generating Polar Plots in Astronomical Images. When a structure displays dependence on distance and azimuthal angle from a center (for example the spiral arms of galaxies or the diffraction spikes of stars), projecting the pixels to polar coordinates greatly simplifies their study. This projection from one pixel grid to another is known as a "polar plot." For this purpose, a new option has been added to the GNU Astronomy Utilities (Gnuastro) in version 0.23 to "astscript-radial-profile" script, which we describe in this research note. The figures of this research note are reproducible with Maneage, on the Git commit 5d34243.

Keywords: Open source software, Astronomy software, Astronomical techniques, Spiral arms, Spiral pitch angle
Chemical Evolution via Dilution of an Initial Reservoir of Heavy Elements. As a possible analog to the type of environment that might have produced the first low-mass metal-containing stars, a model is outlined in which a reservoir of gas containing the first metals begins forming stars upon an inflow of metal-free gas from a surrounding environment. The mass of gas in the reservoir is assumed to initially increase, reach a maximum, and then follow an exponential decline. The stellar metallicity distribution brought about is an example of chemical evolution via dilution of an initial source of metals.

Keywords: Stellar populations, Population II stars, Population III stars
Determination of the Abundance of Mercury from the Hg II Line at 5677.10 Å in Late B-type Stars. III. HD 145389 (ϕ Her) and HD 186122 (46 Aql). The weak line of Hg II located at 5677.10 Å is used to measure the mercury abundance in two HgMn stars, HD 145389 (ϕ Her) and HD 186122 (46 Aql). This line is detected at 3σ above the noise in the adjacent continuum in ϕ Her but not detected in 46 Aql. The synthesis of this line, using the current atomic parameters available in NIST, confirms a large overabundance of mercury in HD 143807, about 4.08 dex, which is actually smaller than the excess derived from the 3983.93 Å line in earlier studies. The synthesis of other lines close to the Hg II line yields excesses in scandium (+1.9 dex), chromium (+1.0 dex) and yttrium (+3.34 dex) in ϕ Her.

Keywords: Mercury-manganese stars, Chemically peculiar stars
Kinematic Association of Two FU Orionis Stars with Young Clusters in Orion. Many known FU Orionis stars are projected on the sky at the peripheries of star-forming regions. Physical association is assumed, but not yet firmly established. We investigate the cases of two such stars, FU Ori and V883 Ori, seeking kinematic evidence of their membership in young clusters associated with the Orion molecular clouds. Using astrometric data from Gaia DR3, we search for consistent 2D velocities, and we also use more limited radial velocity data to assess 3D velocities. Considering +/ ‑ 25 pc boxes centered on λ Ori and the Orion Nebula Cluster, we use the inferred velocity fields to confirm the kinematic association of FU Ori with the former, and V883 Ori with the latter.

Keywords: Young stellar objects, Gaia, FU Orionis stars
Detecting Novel Damped Lyα Absorbers in the Intergalactic Medium. Damped Lyα (DLA) absorbers are a class of quasar absorption line systems that can be used to trace hydrogen evolution and study gas, composition, kinematics, and stellar formation in galaxies or the intergalactic medium in the early universe. In this study, the number of DLA absorbers found with a deep learning algorithm is augmented using metal Mg II absorbers as signposts. The artificial training data was generated by inserting synthetic absorption lines into spectra. Using previously identified DLAs as a test set, the model returned a 94.6% accuracy score and 1197 new DLA absorbers, which nearly doubles the previously known number of samples within the search catalog. Additionally, the column density and Doppler broadening are measured on the newly found DLA absorbers through Voigt profile fitting.

Keywords: Interstellar absorption, Damped Lyman-alpha systems, Quasar absorption line spectroscopy, Intergalactic medium
Color Measurements of Dust Clouds Transiting the White Dwarf J0328-1219. The transiting dust clouds that orbit the white dwarf (WD) J0328-1219 produce dips with nearly identical depths at g' and R bands. This resembles a similar finding for WD 1145+017 at near-IR wavelengths, which has been interpreted as requiring an absence of small particles in the dust clouds. Whereas the lack of depth difference at optical wavelengths for J0328-1219 can be used to rule-out the presence of small particles if the dust clouds are optically thin, a constraint on the particle size distribution is not possible if the dust clouds are optically thick.

Keywords: White dwarf stars
Exploring Viscosity Effects in Accretion Disk Simulations: A Code Comparison between FLASH and Athena. This project investigates the impact of viscosity on the evolution of black hole accretion disks through a comparative analysis between FLASH and Athena simulations. Our focus lies in understanding the role of viscosity in overall disk evolution. We present mass accretion rate plots that reveal near identical patterns in disk evolution when varying viscosity. We emphasize the need for additional code-comparison research, including exploration of a wider variety of codes and physics included to enhance our understanding and confidence in simulated models.

Keywords: Accretion, Hydrodynamical simulations, Black holes
J115307.93+353528.2—Spectroscopic Twin Binary, Composed of Solar Like Stars. Orbital Solution from Poorly Resolved Double-line Structure. We present a study of double-lined spectroscopic binary (SB2) J115307.93+353528.2 based on data from the Large Sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) medium resolution survey (MRS). We use full-spectrum fitting to derive radial velocities and spectral parameters, which suggest that this is a "twin" system of two nearly identical stars, which are similar to the Sun. The orbital solution tells us that it is relatively wide pair of stars on slightly eccentric orbit with period P ≃ 206 days. This result shows that LAMOST-MRS data can be used to detect such twin binaries even when double-line structure is poorly resolved in the spectra. Changes of values from single star model analysis allows us to reliably select such SB2 candidate and to make first estimate of the orbital period.

Keywords: Spectroscopic binary stars
Predicting CO<SUB>2</SUB> Gas Layer Thickness due to Mantle Outgassing in the Exoplanet Census. The exchange of molecules between a planet's interior and exterior is a major component of planetary development and atmospheric formation. Recently, detailed observational studies of exoplanet atmospheres have become possible, enabling robust testing of planetary outgassing models. In this Note, we apply the Dorn et al. stagnant lid model for outgassing to the observed exoplanet census to produce predictions for the atmospheric scale heights that may be observed. We also model atmospheric mass loss due to photoevaporation to determine if the predicted atmospheres would likely be retained and therefore observable.

Keywords: Exoplanet atmospheres
SupSpec: A Python Package for Measuring the Doppler Shifts of Supernova Spectral Lines. Here we present an open-source Python package, SupSpec, which aids in finding the velocity structure of spectral features throughout supernova (SN) ejecta. This code is designed to require minimal user interaction and can ingest an arbitrarily large number of spectra. By fitting a Gaussian distribution to the spectral sequence of a single SN over time, it finds the "velocity structure"—the evolution of the velocity of a specific absorption feature over time. SupSpec is available on GitHub and on Zenodo.

Keywords: Markov chain Monte Carlo, Time domain astronomy, Spectroscopy
Determination of the Abundance of Mercury from the Hg II Line at 5677.10 Å in Late B-type Stars. IV. HD 149121 (28 Her) and HD 178065. The weak line of Hg II located at 5677.10 Å is used to measure the mercury abundance in two HgMn stars, HD 149121 (28 Her) and HD 178065. This line is detected at 3σ above the noise in the adjacent continuum in both stars. The synthesis of this line confirms a large overabundance of mercury, about +4.57 dex in HD 149121, and +3.70 dex in HD 178065, which is less than the excesses derived from the 3983.93 Å line in earlier studies. The presence of previously reported weak emission lines of Ti II at 6106.50 Å and of Cr II at 6158.62 and 6182.30 Å in the spectrum of HD 178065 is confirmed. The synthesis of other lines close to the Hg II line yields estimates of the abundance deficiencies or excesses relative to solar abundances. Oxygen has a solar abundance (0.00 dex), silicon is deficient (‑0.48 dex), iron also (‑0.22 dex) and chromium is overabundant in HD 178065.

Keywords: Mercury-manganese stars, Chemically peculiar stars
Analysis of Gaia DR3 Data of Selected High Galactic Latitude Hα Emission Stars. Gaia DR3 data of 52 high galactic latitude Hα emission stars selected from the paper of Stephenson are analyzed. Ten new variable stars and eight new high velocity stars have been found. Details of six post-AGB stars and several other interesting stars are discussed. Many of the stars presented in this paper have Gaia DR3 light curves and spectra. A detailed study of these 52 stars is needed to derive their chemical composition and to further understand their binarity, circumstellar matter and evolutionary status. The astrophysical parameters from the Gaia DR3 data reveal several hot (OBA) and several F and G-type stars in this sample. Some of them are metal-poor stars.

Keywords: H-alpha stars
JCMT SCUBA-2 Sub-millimeter Observations of AT2018cow. We present a reprocessing of all the submillimeter observations of the optical transient AT2018cow that were performed simultaneously at 850 μm (350 GHz) and 450 μm (670 GHz) using the Submillimetre Common-User Bolometer Array 2 (SCUBA-2), the 10,000 pixel bolometer continuum camera on the James Clerk Maxwell Telescope on Maunakea, Hawai'i. A bright source was detected in our initial observations. The peak in the longer wavelength spectrum had just passed through the SCUBA-2 region prior to our first observation.

Keywords: Submillimeter astronomy, Transient sources, High energy astrophysics
New Spectroscopic Redshift Places PEARLSDG in a Group at ∼124 Mpc. PEARLSDG was previously reported as an isolated dwarf galaxy with a TRGB distance of 30 Mpc. New data show this to not be the case. We report a new spectroscopic redshift of 0.02809, which argues for an association with a group of galaxies at ∼124 Mpc.

Keywords: Stellar populations, Dwarf galaxies, Galaxy stellar content, James Webb Space Telescope, Galaxy evolution, Low surface brightness galaxies
Little Red Dots from Low-spin Galaxies at High Redshifts. Recently, a new population of compact, high-redshift (z ≳ 7) galaxies appeared as little red dots (LRDs) in deep JWST observations. The latest spectroscopic data indicates that these galaxies contain an evolved stellar population, reflecting an early episode of high star formation-rate. The appearance of broad emission lines suggests that a central overmassive black hole also powers these galaxies. I propose that LRD galaxies represent the low-spin tail of the galaxy population. Low-spin galaxies host a more compact gaseous disk with an enhanced star formation rate relative to typical galaxies at the same redshift. The compact disk feeds efficiently a central black hole, as predicted by Eisenstein &amp; Loeb.

Keywords: AGN host galaxies, Compact galaxies
Assessing the Evolution of Solar Cycle 25: A Weak-moderate Cycle. This note aims to analyze the evolution of the sunspot number for Solar Cycle 25, updating our previous findings on this topic. We compare daily, monthly and 13 months smoothed sunspot numbers for Solar Cycle 25 with those from previous cycles since mid-18th century (Solar Cycles 1–25). The highest daily, monthly and 13 months smoothed values for Solar Cycle 25 are significantly lower than the mean and median values considering all cycles. In particular, Solar Cycle 25 ranks 17th in terms of the highest 13 months smoothed sunspot number at this point in the cycle. Based on current data and the progression toward its maximum, we conclude that Solar Cycle 25 is likely to be a weak to moderate cycle, consistent with our earlier analyses. In addition, we find that Solar Cycles 13, 14, and 16 have the most similar behavior to that of Solar Cycle 25. Assuming a cycle length for Solar Cycle 25 similar to those of the above cycles, we estimate that the minimum of Solar Cycle 26 will be in 2030–2031.

Keywords: Solar activity, Sunspot cycle, Solar cycle, Sunspot number
Comet A117uUD Goes Interstellar after Encountering Saturn in 2022. Small solar system bodies may reach hyperbolic orbits after a close interaction with a giant planet. Comet C/1980 E1 (Bowell), with a current value of the eccentricity of 1.057733 ± 0.000008, reached its present-day path after a close encounter with Jupiter in 1980. Comet A117uUD was found by ATLAS South Africa on 2024 June 14. Its current orbit determination, based on 142 observations for a data-arc span of 31 days, places A117uUD among the bodies following hyperbolic orbits (19.51σ, eccentricity of 1.037 ± 0.002). However, it did not come from interstellar space. Here, we show that it reached its current hyperbolic trajectory after a close encounter with Saturn in 2022.

Keywords: Comets, Solar system
OH and H<SUB>2</SUB>O Maser Activities Among Long-period Variables. The distribution within an infrared color–magnitude diagram of variable red giants known to have circumstellar masers is reported. Stars with H2O-maser sources occur within a color and period domain of (J ‑ K  s ) &gt; 1.15 and P &gt; 199 days, respectively, often in the absence of OH masers. By contrast, OH masers are mostly detected among cooler red giants with (J ‑ K  s ) &gt; 1.35 and P &gt; 316 days, and can coexist with H2O-maser sources. The results suggest that red giants must evolve to absolute magnitudes brighter than prior to enabling H2O-maser emission, and possibly expand beyond a certain size before triggering OH masers.

Keywords: Pulsating variable stars, Semi-regular variable stars, Mira variable stars, Circumstellar masers, Long period variable stars
Radio Recombination Line Observations toward the Fermi Bubble. We use Green Bank Telescope radio recombination line (RRL) observations to constrain the morphology of warm ionized gas in the Fermi Bubble. Our limits on hydrogen RRL emission allow us to constrain the emission measure of the ionized gas and to estimate the beam filling factor of previous Wisconsin H-Alpha Mapper observations. Our results indicate that the warm ionized gas on the Fermi Bubble boundary spans at least 1000 pc2 with a depth of less than a pc, suggesting either a sheet-like structure or a structure consisting of many small clumps. Our data will enable us to properly calibrate future Hα observations and aid in calculating the Lyman continuum flux needed to maintain the ionized gas.

Keywords: Warm ionized medium, Interstellar phases, Radio astronomy
Additional Doppler Monitoring Corroborates HAT-P-11c as a Planet. In 2010, Bakos and collaborators discovered a Neptune-sized planet transiting the K-dwarf HAT-P-11 every five days. Later in 2018, Yee and collaborators reported an additional Jovian-mass companion on a nine year orbit based on a decade of Doppler monitoring. The eccentric outer giant HAT-P-11c may be responsible for the peculiar polar orbit of the inner planet HAT-P-11b. However, Basilicata et al. recently suggested that the HAT-P-11c Doppler signal could be caused by stellar activity. In this research note, we extend the Yee et al. Doppler time series by six years. The combined data set spanning 17 yr covers nearly two orbits of the outer planet. Importantly, we observe two periastron passages of planet c and do not observe a coherent activity signature. Together with the previously reported astrometric acceleration of HAT-P-11 from Hipparcos and Gaia, we believe there is strong evidence for HAT-P-11c as a bona fide planet.

Keywords: Radial velocity, Exoplanets
Finding Passive Galaxies in H I-MaNGA: The Impact of Star Formation Rate Indicator. H I-rich galaxies typically have high star formation rates (SFRs), but there exist interesting H I-rich and low star-forming galaxies. Previous work on a sample of these galaxies identified from H I-Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) (H I follow-up to the MaNGA survey) using an infrared indicator of specific-SFR (sSFR; namely W2 ‑ W3 &lt; 2) could find no single physical process to explain their unusual behavior. The method by which galaxies are identified as low sSFR may be important in this conclusion. In this Research Note, we explore how an H I-rich, low sSFR sample of H I-MaNGA galaxies differs using Hα, single stellar population, and ultraviolet estimators of SFR. We find that samples are statistically similar to each other so long as W2 ‑ W3 &lt; 2 is interpreted as corresponding to sSFR &lt; 10‑11.15 yr‑1.

Keywords: Quenched galaxies