In order to study the Milky Way, RR Lyrae (RRL) variable stars identified by Gaia, ASAS-SN, and ZTF sky survey projects have been analyzed as tracers in this work. Photometric and spectroscopic information of 3417 RRLs including proper motions, radial velocity, and metallcity are obtained from observational data of Gaia, LAMOST, GALAH, APOGEE, and RAVE. Precise distances of RRLs with typical uncertainties less than 3% are derived by using a recent comprehensive period–luminosity–metallicity relation. Our results from kinematical and chemical analysis provide important clues for the assembly history of the Milky Way, especially for the Gaia–Sausage ancient merger. The kinematical and chemical trends found in this work are consistent with those of recent simulations that indicated that the Gaia–Sausage merger had a dual origin in the Galactic thick disk and halo. As recent similar works have found, the halo RRL sample in this work contains a subset of radially biased orbits besides a more isotropic component. This higher orbital anisotropy component amounts to β ≃ 0.8, and it contributes between 42% and 83% of the halo RRLs at 4 < R( kpc) < 20.
Ablimit, Iminhaji, et al. "The Milky Way Revealed by Variable Stars. I. Sample Selection of RR Lyrae Stars and Evidence for Merger History." The Astrophysical Journal. Supplement Series, vol. 258, no. 1, Jan. 2022. https://doi.org/10.3847/1538-4365/ac347f
Ablimit, Iminhaji, Zhao, Gang, Teklimakan, Uy, Shi, Jian-Rong, & Abdusalam, Kunduz (2022). The Milky Way Revealed by Variable Stars. I. Sample Selection of RR Lyrae Stars and Evidence for Merger History. The Astrophysical Journal. Supplement Series, 258(1). https://doi.org/10.3847/1538-4365/ac347f
Ablimit, Iminhaji, Zhao, Gang, Teklimakan, Uy, et al., "The Milky Way Revealed by Variable Stars. I. Sample Selection of RR Lyrae Stars and Evidence for Merger History," The Astrophysical Journal. Supplement Series 258, no. 1 (2022), https://doi.org/10.3847/1538-4365/ac347f
@article{osti_1983302,
author = {Ablimit, Iminhaji and Zhao, Gang and Teklimakan, Uy and Shi, Jian-Rong and Abdusalam, Kunduz},
title = {The Milky Way Revealed by Variable Stars. I. Sample Selection of RR Lyrae Stars and Evidence for Merger History},
annote = {In order to study the Milky Way, RR Lyrae (RRL) variable stars identified by Gaia, ASAS-SN, and ZTF sky survey projects have been analyzed as tracers in this work. Photometric and spectroscopic information of 3417 RRLs including proper motions, radial velocity, and metallcity are obtained from observational data of Gaia, LAMOST, GALAH, APOGEE, and RAVE. Precise distances of RRLs with typical uncertainties less than 3% are derived by using a recent comprehensive period–luminosity–metallicity relation. Our results from kinematical and chemical analysis provide important clues for the assembly history of the Milky Way, especially for the Gaia–Sausage ancient merger. The kinematical and chemical trends found in this work are consistent with those of recent simulations that indicated that the Gaia–Sausage merger had a dual origin in the Galactic thick disk and halo. As recent similar works have found, the halo RRL sample in this work contains a subset of radially biased orbits besides a more isotropic component. This higher orbital anisotropy component amounts to β ≃ 0.8, and it contributes between 42% and 83% of the halo RRLs at 4 < R( kpc) < 20.},
doi = {10.3847/1538-4365/ac347f},
url = {https://www.osti.gov/biblio/1983302},
journal = {The Astrophysical Journal. Supplement Series},
issn = {ISSN 0067-0049},
number = {1},
volume = {258},
place = {United States},
publisher = {IOP Publishing},
year = {2022},
month = {01}}
US Department of Energy (USDOE), Washington, DC (United States). Office of Science, Sloan Digital Sky Survey (SDSS)
Sponsoring Organization:
Alfred P. Sloan Foundation; Gordon and Betty Moore Foundation; National Aeronautics and Space Administration (NASA); National Science Foundation (NSF); USDOE Office of Science (SC)
Contributing Organization:
Lawrence Berkeley National Laboratory (LBNL); Los Alamos National Laboratory (LANL)
OSTI ID:
1983302
Journal Information:
The Astrophysical Journal. Supplement Series, Journal Name: The Astrophysical Journal. Supplement Series Journal Issue: 1 Vol. 258; ISSN 0067-0049