Search Publications
Feasibility of Observing Gamma-Ray Polarization from Cygnus X-1 Using a CubeSat
Chang, Hsiang-Kuang; Laurent, Philippe; Rodriguez, Jerome +7 more
Instruments flown on CubeSats are small. Meaningful applications of CubeSats in astronomical observations rely on the choice of a particular subject that is feasible for CubeSats. Here we report the result of a feasibility study for observing gamma-ray polarization from Cygnus X-1 using a small Compton polarimeter on board a 3U CubeSat. Silicon de…
Two-epoch Orbit Estimation for Wide Binaries Resolved in Hipparcos and Gaia
Makarov, Valeri V.
The Hipparcos catalog and its Double and Multiple System Annex (DMSA) lists 4099 components with individual proper motions and coordinates on the epoch 1991.25. Many of these long-period binary stars are also present in Gaia Data Release 2 (DR2). Using the available relative positions and proper motions separated by 24.25 yr, the equations of rela…
The Complex Rotational Light Curve of (385446) Manwë-Thorondor, a Multicomponent Eclipsing System in the Kuiper Belt
Verbiscer, Anne J.; Grundy, William M.; Thirouin, Audrey +2 more
Kuiper Belt Object (385446) Manwë-Thorondor is a multiobject system with mutual events predicted to occur from 2014 to 2019. To detect the events, we observed the system at 4 epochs (UT 2016 August 25 and 26, 2017 July 22 and 25, 2017 November 9, and 2018 October 6) in g, r, and VR bands using the 4 m SOAR and the 8.1 m Gemini South telescopes at …
Kepler Binary Stars in the NGC 6819 Open Cluster: KIC 5113146 and KIC 5111815
Bilir, Selçuk; Soydugan, Faruk; Soydugan, Esin +1 more
In this study, an investigation of two double-lined binary stars KIC 5113146 and KIC 5111815 in the NGC 6819 open cluster is presented based on both photometric and spectroscopic data. Simultaneous analysis of light and radial velocity curves was made and the absolute parameters of the systems' components were determined for the first time. We fin…
An Information Theory Approach on Deciding Spectroscopic Follow-ups
Astudillo, Javiera; Protopapas, Pavlos; Pichara, Karim +1 more
Classification and characterization of variable phenomena and transient phenomena are critical for astrophysics and cosmology. These objects are commonly studied using photometric time series or spectroscopic data. Given that many ongoing and future surveys are conducted in a time domain, and given that adding spectra provides further insights but…
The Hubble Space Telescope's Near-UV and Optical Transmission Spectrum of Earth as an Exoplanet
Roberge, Aki; France, Kevin; Youngblood, Allison +3 more
We observed the 2019 January total lunar eclipse with the Hubble Space Telescope's STIS spectrograph to obtain the first near-UV (1700-3200 Å) observation of Earth as a transiting exoplanet. The observatories and instruments that will be able to perform transmission spectroscopy of exo-Earths are beginning to be planned, and characterizing the tra…
Outflow from Outer-arm Starburst in a Grazing Collision between Galaxies
Brinks, Elias; Struck, Curtis; Elmegreen, Bruce G. +5 more
Gemini NIFS K-band spectra and Atacama Large Millimeter/submillimeter Array 12CO $J=1\to 0, HCO+, and 100 GHz continuum observations are used to study a bright starburst clump on an outer arm of the interacting galaxy NGC 2207. This clump emits 23% of the total 24 µm flux of the galaxy pair and has an optically opaque d…
Identification of Possible Stellar Companions via Speckle Interferometry in a Sample of Be Stars
Borges Fernandes, M.; Guerrero, C. A.; Souza, T. B.
We present speckle interferometric measurements of Be stars made with the 1.60 m Perkin-Elmer telescope at the Pico dos Dias Observatory of the Laboratório Nacional de Astrofísica in Brazil. Using three different filters (V, R, and I), we obtained astrometric measurements for 23 stars, during three observing runs allocated in 2017 March, 2018 Apri…
A Search for Extra-tidal RR Lyrae in Globular Clusters NGC 5024 and NGC 5053
Riddle, Reed; Rusholme, Ben; Kaplan, David L. +9 more
Recently, Kundu et al. reported that the globular cluster NGC 5024 (M53) possesses five extra-tidal RR Lyrae. In fact, four of them were instead known members of a nearby globular cluster NGC 5053. The status of the remaining extra-tidal RR Lyrae is controversial depending on the adopted tidal radius of NGC 5024. We have also searched for addition…
BD+14°3061: A Luminous Yellow Post-AGB Star in the Galactic Halo
Bond, Howard E.
I report the discovery that the ninth-mag Galactic-halo star BD+14°3061 is a member of the rare class of luminous metal-poor "yellow post-AGB" stars. Its Gaia DR2 parallax implies an absolute magnitude of MV = -3.44 ± 0.27, and it is a very high-velocity star moving in a retrograde Galactic orbit. BD+14°3061 is a field analog of the hal…