Search Publications
Discovery of a young pre-intermediate polar
Hermes, J. J.; Drake, Jeremy J.; Landstreet, John D. +4 more
We present the discovery of a magnetic field on the white dwarf component in the detached post-common envelope binary (PCEB) CC Cet. Magnetic white dwarfs in detached PCEBs are extremely rare, in contrast to the high incidence of magnetism in single white dwarfs and cataclysmic variables. We find Zeeman-split absorption lines in both ultraviolet H…
Extinction in the Large Magellanic Cloud Bar around NGC 1854, NGC 1856, and NGC 1858
Milone, Antonino P.; Panagia, Nino; De Marchi, Guido
We report on the extinction properties in the fields around the clusters NGC 1854, NGC 1856, and NGC 1858 in the bar of the Large Magellanic Cloud. The color-magnitude diagrams of the stars in all these regions show an elongated red giant clump that reveals a variable amount of extinction across these fields, ranging from A V ≃ 0.2 to…
M-subdwarf Research. II. Atmospheric Parameters and Kinematics
Qin, Li; Luo, A. -Li; Hou, Wen +12 more
We applied the revised M subdwarf classification criteria discussed in Zhang et al. to Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR7 and combined the result with the M subdwarf sample from Savcheva et al. to construct a new M subdwarf sample for further study. The atmospheric parameters for each object were derived from fi…
Multiwavelength observations reveal a faint candidate black hole X-ray binary in IGR J17285-2922
Maccarone, T. J.; Degenaar, N.; Wijnands, R. +18 more
IGR J17285-2922 is a known X-ray binary with a low peak 2-10 keV X-ray luminosity of ~ 1036 erg s-1 during outburst. IGR J17285-2922 exhibited two outbursts in 2003 and 2010 and went into outburst again in 2019. We have monitored this ~ 4-month long 2019 outburst with Swift in X-ray and the Very Large Array in radio. We have …
Core-collapse supernova subtypes in luminous infrared galaxies
Gromadzki, M.; Galbany, L.; Inserra, C. +34 more
The fraction of core-collapse supernovae (CCSNe) occurring in the central regions of galaxies is not well constrained at present. This is partly because large-scale transient surveys operate at optical wavelengths, making it challenging to detect transient sources that occur in regions susceptible to high extinction factors. Here we present the di…
SCExAO/CHARIS Direct Imaging of A Low-mass Companion At A Saturn-like Separation from an Accelerating Young A7 Star
Currie, Thayne; Kwon, Jungmi; Tamura, Motohide +18 more
We present the SCExAO direct imaging discovery and characterization of a low-mass companion to the nearby young A7IV star, HD 91312. SCExAO/CHARIS JHK (1.1-2.4 µm) spectra and SCExAO/HiCIAO H-band imaging identify the companion over a two year baseline in a highly inclined orbit with a maximum projected separation of 8 au. The companion, HD …
Individual dynamical masses of DENIS J063001.4-184014AB reveal a likely young brown dwarf triple
Martín, E. L.; Sahlmann, J.; Burgasser, A. J. +6 more
The binary nature of the M8.5 dwarf DENIS J063001.4-184014AB (DE0630-18) was discovered with astrometric monitoring from the ground, which determined the unresolved photocentric orbit and the trigonometric parallax of the system. Here we present radial velocity monitoring and resolved observations in the near-infrared with Keck aperture masking th…
Fundamental parameters for 30 faint open clusters with Gaia EDR3 based on the more reliable members
Ding, Xu; Yu, Xiao-Guang; Ji, Kai-Fan +4 more
An open cluster is an ideal region to study the evolution of stars. In this work, we use Gaia Early Data Release 3 (Gaia EDR3) to derive the fundamental parameters of 30 faint open clusters listed in the catalogue given by Cantat-Gaudin et al. (2018, A&A, 618, A93), but the G magnitude of all of the member stars of that catalogue is brighter t…
YY Hya and its interstellar environment
Thorstensen, John R.; Fesen, Robert A.; Przybilla, Norbert +7 more
Context. During a search for previously unknown Galactic emission nebulae, we discovered a faint 36' diameter Hα emission nebula centered around the periodic variable YY Hya. Although this star has been classified as an RR-Lyr variable, such a classification is inconsistent with a Gaia distance of ≃450 pc. The GALEX image data also show YY Hya as …
Impact of gradients at the martian terminator on the retrieval of ozone from SPICAM/MEx
Aoki, S.; Vandaele, A. C.; Daerden, F. +11 more
Rapid variations of pressure, temperature and illumination at the day-night terminator have the potential to cause asymmetries in the abundance distribution of the atmosphere constituents along the line of sight (LOS) of a solar occultation experiment. Ozone, in particular, displays steep density gradients across the terminator of Mars due to phot…