Three new late-type hypervelocity star candidates from Gaia DR2 with refined selection criteria

Li J, Jia S, Gao Y, Jiang DK, Kupfer T, Heber U, Liu C, Chen XF, Han ZW (2020)

Publication Type: Journal article

Publication year: 2020

Journal

Research in Astronomy and Astrophysics IOP Publishing

Book Volume: 20

Journal Issue: 3

DOI: 10.1088/1674-4527/20/3/42

Abstract

Several dozen hypervelocity star (HVS) candidates have been reported based on the second data release of Gaia (Gaia DR2). However, it has been proven that the radial velocities of some Gaia HVS candidates are not reliable. In this paper, we employ refined astrometric criteria to re-examine Gaia DR2, arriving at a more reliable sample of HVS and high velocity star candidates than those found by previous authors. We develop a method called Binary Escape Probability Analysis to identify some HVS candidates. This method allows us to work with stars having only two epochs of measured radial velocity. These stars were usually discarded in previous similar studies. A scrutiny of our final results sheds light on selection effects present in our studies, which we propose to be the focus of future studies. In total, we find three late-type (2 G-type and 1 K-type) HVS and 21 high velocity star candidates, 3 and 11 of which are new, respectively. Judging by their historical trajectories, which we calculate, all three HVS candidates could not have had Galactic center origins. Further monitoring is required to confirm their status.

Authors with CRIS profile

Ulrich Heber Naturwissenschaftliche Fakultät

Involved external institutions

Chinese Academy of Sciences (CAS) / 中国科学院 CN China (CN) University of California US United States (USA) (US)

How to cite

APA:

Li, J., Jia, S., Gao, Y., Jiang, D.-K., Kupfer, T., Heber, U.,... Han, Z.-W. (2020). Three new late-type hypervelocity star candidates from Gaia DR2 with refined selection criteria. Research in Astronomy and Astrophysics, 20(3). https://doi.org/10.1088/1674-4527/20/3/42

MLA:

Li, Jiao, et al. "Three new late-type hypervelocity star candidates from Gaia DR2 with refined selection criteria." Research in Astronomy and Astrophysics 20.3 (2020).

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