Search Publications
Updated High-temperature Opacities for the Dartmouth Stellar Evolution Program and Their Effect on the Jao Gap Location
Boudreaux, Emily M.; Chaboyer, Brian C.
The Jao Gap, a 17% decrease in stellar density at M G ~ 10 identified in both Gaia Data Release 2 and Early Data Release 3, presents a new method to probe the interior structure of stars near the fully convective transition mass. The Gap is believed to originate from convective-kissing instability wherein asymmetric production of
The Interstellar Medium Scaling Relations Using Inner H I and an Application of Estimating Dust Mass
Lin, Zesen; Kong, Xu; Li, Fujia +4 more
We select a disk-like galaxy sample with observations of the H I, H2, and dust from the Herschel Reference Survey, and derive inner H I masses within the optical radius. We find that the inner gas-to-dust ratio is almost independent of gas-phase metallicity, and confirm that the inner gas mass (H I+H2) shows a tighter relatio…
Searching for C II Emission from the First Sample of z ∼ 6 O I Absorption-associated Galaxies with the Atacama Large Millimeter/submillimeter Array
Hennawi, Joseph F.; Fan, Xiaohui; Prochaska, J. Xavier +13 more
We report the first statistical analyses of [C II] and dust continuum observations in six strong O I absorber fields at the end of the reionization epoch obtained by the Atacama Large Millimeter/submillimeter Array (ALMA). Combined with one [C II] emitter reported in Wu et al., we detect one O I-associated [C II] emitter in six fields. At redshift…
X-Ray Studies of Blazar 1ES 1959+650 Using Swift and XMM-Newton Satellite
Gaur, Haritma; Wani, Kiran; Patil, M. K.
High synchrotron energy peaked blazar 1ES 1959+650 was studied with the Swift and XMM-Newton satellites in a total of 127 observations during the period 2018 June-2020 December. We extensively studied its flux and spectral variability on intraday and long-term timescales. Discrete correlation function analysis between soft and hard X-ray bands ind…
Very Metal-poor Stars in the Solar Vicinity: Kinematics and Abundance Analysis
Villanova, Sandro; Carraro, Giovanni; Plotnikova, Anastasiia +1 more
Very metal-poor stars contain crucial information on the Milky Way's infancy. In our previous study we derived a mean age of ~13.7 Gyr for a sample of these stars in the Sun's vicinity. In this work, we investigate the chemical and kinematic properties of these stars with the goal of obtaining some insights into their origin and their parent popul…
Mid-IR Observations of IRAS, AKARI, WISE/NEOWISE, and Subaru for Large Icy Asteroid (704) Interamnia: A New Perspective of Regolith Properties and Water Ice Fraction
Zhao, Yuhui; Ji, Jianghui; Yang, Bin +3 more
(704) Interamnia is one of the largest asteroids located in the outer main-belt region, which may contain a large amount of water ice underneath its surface. We observe this asteroid using 8.2 m Subaru telescope at mid-infrared wave bands and utilize a thermophysical model for realistic surface layers to analyze mid-infrared data from Subaru along…
XMM-Newton Observations of Two Archival X-Ray Weak Type 1 Quasars: Obscuration Induced X-Ray Weakness and Variability
Brandt, W. N.; Luo, Bin; Yi, Weimin +6 more
We report XMM-Newton observations of two examples of an unclassified type of X-ray weak quasars from the Pu et al. survey of X-ray weak quasars in the Chandra archive, SDSS J083116.62+321329.6 at z = 1.797 and SDSS J142339.87+042041.1 at z = 1.702. They do not belong to the known populations of X-ray weak quasars that show broad absorption lines, …
The Similar Seven: A Set of Very Alike Exoplanets to Test Correlations between System Parameters and Atmospheric Properties
López-Morales, Mercedes; Jordán, Andrés; Brahm, Rafael +1 more
Studies of exoplanetary atmospheres have found no definite correlations between observed high-altitude aerosols and other system parameters. This could be, in part, because of the lack of homogeneous exoplanet samples for which specific parameters can be isolated and inspected. Here, we present a set of seven exoplanets with very similar system pa…
Post-outburst Evolution of Bona Fide FU Ori-type V2493 Cygnus: A Spectro-photometric Monitoring
Irawati, Puji; Pandey, Rakesh; Sharma, Saurabh +11 more
We present here the results of 8 yr of our near-simultaneous optical-near-infrared spectro-photometric monitoring of the bona fide FU Ori (FUor)-type candidate V2493 Cygnus (V2493 Cyg) starting from 2013 September to 2021 June. During our optical monitoring period (between 2015 October 16 and 2019 December 30), the V2493 Cyg is slowly dimming with…
Identification of 1RXS J165424.6-433758 as a Polar Cataclysmic Variable
Mukai, K.; Troja, E.; Cenko, S. B. +25 more
We present the results of our X-ray, ultraviolet, and optical follow-up campaigns of 1RXS J165424.6-433758, an X-ray source detected with the Swift Deep Galactic Plane Survey. The source X-ray spectrum (Swift and NuSTAR) is described by thermal bremsstrahlung radiation with a temperature of kT = 10.1 ± 1.2 keV, yielding an X-ray (0.3-10 keV8) lumi…