期刊
ASTROPHYSICAL JOURNAL
卷 711, 期 1, 页码 138-143出版社
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/711/1/138
关键词
stars: abundances; stars: atmospheres; stars: distances; stars: early-type; stars: individual (HIP 60350; 18 Peg); stars: kinematics and dynamics
资金
- Deutsche Forschungsgemeinschaft (DFG) [He1356/50-1, He1356/52-1, He1356/45-1]
Young, massive stars in the Galactic halo are widely supposed to be the result of an ejection event from the Galactic disk forcing some stars to leave their place of birth as so-called runaway stars. Here, we present a detailed spectroscopic and kinematic analysis of the runaway B star HIP 60350 to determine which runaway scenario-a supernova explosion disrupting a binary system or dynamical interaction in star clusters-may be responsible for HIP 60350's peculiar orbit. Based on a non-local thermodynamic equilibrium approach, a high-resolution optical echelle spectrum was examined to revise spectroscopic quantities and for the first time to perform a differential chemical abundance analysis with respect to the B-type star 18 Peg. The results together with proper motions from the Hipparcos Catalog further allowed the three-dimensional kinematics of the star to be studied numerically. The abundances derived for HIP 60350 are consistent with a slightly supersolar metallicity agreeing with the kinematically predicted place of birth similar to 6 kpc away from the Galactic center. However, they do not exclude the possibility of an alpha-enhanced abundance pattern expected in the case of the supernova scenario. Its outstanding high Galactic rest-frame velocity of 530 +/- 35 km s(-1) is a consequence of ejection in the direction of Galactic rotation and slightly exceeds the local Galactic escape velocity in a standard Galactic potential. Hence, IIIP 60350 may be unbound to the Galaxy.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据