Systematic search for blue hyper-velocity stars from LAMOST survey

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Sun, Yongkang, Huang, Yang, Liu, Jifeng, Fu, Haozhu, Zhang, Huawei, Li, Yinbi, Du, Cuihua, Shi, Jianrong, Kong, Xiao
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866915251727892480
author Sun, Yongkang
Huang, Yang
Liu, Jifeng
Fu, Haozhu
Zhang, Huawei
Li, Yinbi
Du, Cuihua
Shi, Jianrong
Kong, Xiao
author_facet Sun, Yongkang
Huang, Yang
Liu, Jifeng
Fu, Haozhu
Zhang, Huawei
Li, Yinbi
Du, Cuihua
Shi, Jianrong
Kong, Xiao
contents Hypervelocity stars (HVSs) represent a unique class of objects capable of escaping the gravitational pull of the Milky Way due to extreme acceleration events, such as close encounters with the supermassive black hole at the Galactic center (GC), supernova explosions in binary systems, or multi-body dynamical interactions. Finding and studying HVSs are crucial to exploring these ejection mechanisms, characterizing central black holes, probing the GC environment, and revealing the distribution of dark matter in our galaxy. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic surveys have so far identified four B-type unbound HVSs. To expand this sample with the second-phase LAMOST survey that started in 2018, we conducted a systematic search for early-type HVSs using the LAMOST Data Release 10. We identified 125 early-type high-velocity candidates with total velocities exceeding 300 km\,s$^{-1}$. Among them, we report ten new unbound B- and A-type hypervelocity star (HVS) candidates (designated LAMOST-HVS5 through LAMOST-HVS14), tripling the number of unbound HVSs previously identified by LAMOST. Kinematic analyses suggest that these newly discovered HVS candidates likely originated either from the Galactic Center or via dynamical interactions. Future high-resolution follow-up observations promise to refine the stellar parameters, distances, and elemental abundances of these candidates, thereby providing deeper insights into their origins and broadening their potential applications across astrophysics.
format Preprint
id arxiv_https___arxiv_org_abs_2504_14836
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Systematic search for blue hyper-velocity stars from LAMOST survey
Sun, Yongkang
Huang, Yang
Liu, Jifeng
Fu, Haozhu
Zhang, Huawei
Li, Yinbi
Du, Cuihua
Shi, Jianrong
Kong, Xiao
Astrophysics of Galaxies
Solar and Stellar Astrophysics
Hypervelocity stars (HVSs) represent a unique class of objects capable of escaping the gravitational pull of the Milky Way due to extreme acceleration events, such as close encounters with the supermassive black hole at the Galactic center (GC), supernova explosions in binary systems, or multi-body dynamical interactions. Finding and studying HVSs are crucial to exploring these ejection mechanisms, characterizing central black holes, probing the GC environment, and revealing the distribution of dark matter in our galaxy. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic surveys have so far identified four B-type unbound HVSs. To expand this sample with the second-phase LAMOST survey that started in 2018, we conducted a systematic search for early-type HVSs using the LAMOST Data Release 10. We identified 125 early-type high-velocity candidates with total velocities exceeding 300 km\,s$^{-1}$. Among them, we report ten new unbound B- and A-type hypervelocity star (HVS) candidates (designated LAMOST-HVS5 through LAMOST-HVS14), tripling the number of unbound HVSs previously identified by LAMOST. Kinematic analyses suggest that these newly discovered HVS candidates likely originated either from the Galactic Center or via dynamical interactions. Future high-resolution follow-up observations promise to refine the stellar parameters, distances, and elemental abundances of these candidates, thereby providing deeper insights into their origins and broadening their potential applications across astrophysics.
title Systematic search for blue hyper-velocity stars from LAMOST survey
topic Astrophysics of Galaxies
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2504.14836