60 Candidate High-velocity Stars Originating from the Sagittarius Dwarf Spheroidal Galaxy in Gaia EDR3

Li, Hefan and Du, Cuihua and Ma, Jun and Shi, Jianrong and Newberg, Heidi Jo and Piao, Yunsong (2022) 60 Candidate High-velocity Stars Originating from the Sagittarius Dwarf Spheroidal Galaxy in Gaia EDR3. The Astrophysical Journal Letters, 933 (1). L13. ISSN 2041-8205

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Abstract

Using proper motions from Gaia Early Data Release 3 (Gaia EDR3) and radial velocities from several surveys, we identify 60 candidate high-velocity stars with a total velocity greater than 75% of the escape velocity that probably originated from the Sagittarius dwarf spheroidal galaxy (Sgr) by orbital analysis. Sgr's gravity has little effect on the results and the Large Magellanic Cloud's gravity has a nonnegligible effect on only a few stars. The closest approach of these stars to the Sgr occurred when the Sgr passed its pericenter (∼38.2 Myr ago), which suggests they were tidally stripped from the Sgr. The positions of these stars in the Hertzsprung–Russell diagram and the chemical properties of 19 of them with available [Fe/H] are similar to the Sgr stream member stars. This is consistent with the assumption of their accretion origin. Two of the 60 are hypervelocity stars, which may also be produced by the Hills mechanism.

Item Type: Article
Subjects: East India Archive > Physics and Astronomy
Depositing User: Unnamed user with email support@eastindiaarchive.com
Date Deposited: 25 Apr 2023 07:10
Last Modified: 04 Sep 2024 04:27
URI: http://ebooks.keeplibrary.com/id/eprint/952

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