Search Publications
Lyα Observations of High Radial Velocity Low-mass Stars Ross 1044 and Ross 825
Shkolnik, Evgenya L.; Schneider, Adam C.; Barman, Travis S. +1 more
The discovery of habitable zone (HZ) planets around low-mass stars has highlighted the need for a comprehensive understanding of the radiation environments in which such planets reside. Of particular importance is knowledge of the far-ultraviolet (FUV) radiation, as low-mass stars are typically much more active than solar-type stars and the proxim…
Gaia GraL: Gaia DR2 gravitational lens systems. IV. Keck/LRIS spectroscopic confirmation of GRAL 113100-441959 and model prediction of time delays
Djorgovski, S. G.; Stern, D.; Surdej, J. +17 more
We report the spectroscopic confirmation and modeling of the quadruply imaged quasar GRAL 113100-441959, the first gravitational lens (GL) to be discovered from a machine learning technique that only relies on the relative positions and fluxes of the observed images without considering colour informations. Follow-up spectra obtained with Keck/LRIS…
Kinematics of the Galaxy from a Sample of Young Open Star Clusters with Data from the Gaia DR2 Catalogue
Bobylev, V. V.; Bajkova, A. T.
We have selected a sample of 326 young (log t < 8) open star clusters with the proper motions and distances calculated by various authors from Gaia DR2 data. The mean values of their line-of-sight velocities have also been taken from various publications. As a result of our kinematic analysis, we have found the following parameters of the angul…
Probing the unidentified Fermi blazar-like population using optical polarization and machine learning
Blinov, D.; Liodakis, I.
The Fermi γ-ray space telescope has revolutionized our view of the γ-ray sky and the high-energy processes in the Universe. While the number of known γ-ray emitters has increased by orders of magnitude since the launch of Fermi, there is an ever increasing number of, now more than a thousand, detected point sources whose low-energy counterpart is …
Detection of metal-rich, cool-warm gas in the outskirts of galaxy clusters
Charlton, Jane C.; Nagai, Daisuke; Pradeep, Jayadev +3 more
We present an ultraviolet quasar absorption line analysis of metal lines associated with three strong intervening H I absorbers (with N(H I) > 1016.5 cm-2) detected in the outskirts of Sunyaev-Zel'dovich (SZ) effect-selected galaxy clusters (zcl ∼ 0.4-0.5), within clustocentric impact parameters of ρcl
The hierarchical triple nature of the former red nova precursor candidate KIC 9832227
Hartman, Joel D.; Bakos, Gáspár Á.; Kovacs, Geza
We revisit the issue of period variation of the recently claimed red nova precursor candidate KIC 9832227. By using the data gathered during the main mission of the Kepler satellite, and data collected by ground-based wide-field surveys and other monitoring programs (such as ASAS-SN), we find that the currently available timing data strongly suppo…
First Assessment of the Binary Lens OGLE-2015-BLG-0232
Bennett, D. P.; Soszyński, I.; Udalski, A. +54 more
We present an analysis of the microlensing event OGLE-2015-BLG-0232. This event is challenging to characterize for two reasons. First, the light curve is not well sampled during the caustic crossing due to the proximity of the full Moon impacting the photometry quality. Moreover, the source brightness is difficult to estimate because this event is…
Surface magnetic activity of the fast-rotating G5 giant IN Comae, central star of the faint planetary nebula LoTr 5
Strassmeier, K. G.; Weber, M.; Ilyin, I. +8 more
Context. On the asymptotic giant branch, low to intermediate mass stars blow away their outer envelopes, forming planetary nebulae. Dynamic interaction between the planetary nebula and its central progenitor is poorly understood. The interaction is even more complex when the central object is a binary star with a magnetically active component, as …
Global Spectral Properties and Lithology of Mercury: The Example of the Shakespeare (H-03) Quadrangle
Capaccioni, F.; Doressoundiram, A.; Perna, D. +4 more
The MErcury Surface, Space ENvironment, GEochemistry and Ranging mission showed the surface of Mercury with an accuracy never reached before. The morphological and spectral analyses performed thanks to the data collected between 2008 and 2015 revealed that the Mercurian surface differs from the surface of the Moon, although they look visually very…
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…