Constraints on the Assembly History of the Milky Way's Smooth, Diffuse Stellar Halo from the Metallicity-dependent, Radially Dominated Velocity Anisotropy Profiles Probed with K Giants and BHB Stars Using LAMOST, SDSS/SEGUE, and Gaia

• Published in: The Astrophysical journal Vol. 919; no. 1; pp. 66 - 92
• Main Authors: Bird, Sarah A., Xue, Xiang-Xiang, Liu, Chao, Shen, Juntai, Flynn, Chris, Yang, Chengqun, Zhao, Gang, Tian, Hai-Jun
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 01.09.2021; IOP Publishing
• Subjects: Anisotropy; Astrophysics; Galactic mass; Horizontal branch stars; Metallicity; Milky Way; Milky Way stellar halo; Sky surveys (astronomy)

We analyze the anisotropy profile of the Milky Way’s smooth, diffuse stellar halo using the Sloan Digital Sky Survey (SDSS) SEGUE blue horizontal branch stars and the SDSS/SEGUE and LAMOST K giants. These intrinsically luminous stars allow us to probe the halo to approximately 100 kpc from the Galac...