Search Publications
The 2L1S/1L2S Degeneracy for Two Microlensing Planet Candidates Discovered by the KMTNet Survey in 2017
Kim, S. -L.; Lee, C. -U.; Bennett, D. P. +49 more
We report two microlensing planet candidates discovered by the Korea Microlensing Telescope Network (KMTNet) survey in 2017. However, both events have the 2L1S/1L2S degeneracy, which is an obstacle to claiming the discovery of the planets with certainty unless the degeneracy can be resolved. For KMT-2017-BLG-0962, the degeneracy cannot be resolved…
The Giant Herbig-Haro Flow HH 212 and Associated Star Formation
Bally, John; Raga, A. C.; Geballe, T. R. +5 more
The bipolar jet HH 212 is one of the finest collimated jets known. It has up to now been detected only in near-infrared H2 emission, but here we present deep optical images that show that two of the major bow shocks are weakly detected in optical [S II] emission, as expected for a bona fide Herbig-Haro jet. We also present widefield H
Spectroscopic Orbits of Subsystems in Multiple Stars. V.
Tokovinin, Andrei
Spectroscopic orbits are determined for inner subsystems in nine stellar hierarchies (HIP 2863, 4974, 8353, 28796, 35261, 92929, 115272, 115552, and 117596). Their periods range from 2.5 to 312 days. For each system, estimates of masses, orbital inclination, and other parameters are given.
The Pulsating Eclipsing Binary TIC 309658221 in a 7.59-day Orbit
Kristiansen, Martti H.; Hong, Kyeongsoo; Lee, Jae Woo
We present a new eclipsing binary (EB) showing multiperiodic oscillations using the first three sectors of Transiting Exoplanet Survey Satellite (TESS) photometry. The eclipse and pulsation light curves of TIC 309658221 were modeled using an iterative method to obtain a consistent photometric solution. The TESS target is a circular-orbit, detached…
Radial Velocities in the Outermost Disk toward the Anticenter
Allende Prieto, C.; López-Corredoira, M.; Sylos Labini, F. +1 more
We measure the mean Galactocentric radial component of the velocity of stars (v R ) in the disk at 8 kpc < R < 28 kpc in the direction of the anticenter. For this, we use the Apache Point Galactic Evolution Experiment. Furthermore, we compare the result with H I maps along the same line of sight. We find an increase in positive (…
X-Ray Observations of an Intermediate Polar V2400 Oph
Pandey, J. C.; Singh, Harinder P.; Joshi, Arti
Based on the X-ray observations from XMM-Newton and Suzaku satellites at four different epochs, we present temporal and spectral properties of an intermediate polar (IP) V2400 Oph (=RX J1712.6-2414). The X-ray variations are found to occur at the spin and synodic periods and are derived to be 929 s and 1003 s, respectively. The X-ray spectrum is s…
The Discovery of Quasi-stellar Objects behind M31 and M33
Massey, Philip; Levesque, Emily M.; Neugent, Kathryn F.
We report the discovery of 11 newly found quasars behind the stellar disks of the spiral galaxies M31 and M33 in the fields covered by the Local Group Galaxy Survey. Their redshifts range from 0.37 to 2.15. Most are X-ray, ultraviolet, and infrared sources. We also report the discovery of five normal background galaxies. Most of these objects were…
Active Asteroid P/2017 S5 (ATLAS)
Mutchler, Max; Kotulla, Ralf; Jewitt, David +7 more
Observations of active asteroid P/2017 S5 when near perihelion reveal the ejection of large (102-104 µm) particles at 0.2-2 m s-1 speeds, with estimated mass-loss rates of a few kg s-1. The protracted nature of the mass loss (continuous over ∼150 days) is compatible with a sublimation origin, meani…
Identification of Stellar Flares Using Differential Evolution Template Optimization
Kowalski, Adam F.; Wisniewski, John P.; Bellm, Eric C. +2 more
We explore methods for the identification of stellar flare events in irregularly sampled data of ground-based time domain surveys. In particular, we describe a new technique for identifying flaring stars, which we have implemented in a publicly available Python module called “PyVAN.” The approach uses the Differential Evolution algorithm to optimi…
New Constraint on the Atmosphere of (50000) Quaoar from a Stellar Occultation
Kobayashi, Naoto; Maehara, Hiroyuki; Matsunaga, Noriyuki +35 more
We report observations of a stellar occultation by the classical Kuiper Belt object (50000) Quaoar that occurred on 2019 June 28. A single-chord high-cadence (2 Hz) photometry data set was obtained with the Tomo-e Gozen CMOS camera mounted on the 1.05 m Schmidt telescope at Kiso Observatory. The obtained ingress and egress data do not show any ind…