Virgo星系早型星系中低质量X射线二元组与全球星团的联系:光学属性
摘要
(已删略) 我们对11个早型星系进行X射线和哈勃ACS观测,探索低质量X射线二元组(LMXB)与全球星团(GC)的联系。我们研究了270个含有LMXB的GC和6488个不含LMXB的GC。更质量、更红、更紧凑的GC更可能包含LMXB。与银河系GC不同,大量含有LMXB的GC的半衰减时间>2.5 Gyr。我们拟合LMXB/GC预期数\lambda_t关于GC质量M、颜色(g-z)和半衰减半径r_{h,cor}的依赖关系,发现\lambda_t \propto M^{1.24\pm0.08} 10^{0.9^{+0.2}_{-0.1} (g-z)} r_{h,cor}^{-2.2^{+0.3}_{-0.4}}。我们的拟合排除了LMXB/GC数与GC质量成线性比例,且大多数高X射线亮度GC只包含单个LMXB的可能性。\lambda_t对GC属性的详细依赖关系基本等价于对相遇率\Gamma_h和金属丰度Z的依赖,\lambda_t \propto \Gamma_h^{0.82\pm0.05} Z^{0.39\pm0.07}。我们的分析提供了强有力的证据表明,动力学形成和金属丰度是决定外星系GC中LMXB存在的主要因素。
引用
@article{arxiv.astro-ph/0611237,
title = {The Low-Mass X-ray Binary and Globular Cluster Connection in Virgo Cluster Early-type Galaxies: Optical Properties},
author = {Gregory R. Sivakoff and Andrés Jordán and Craig L. Sarazin and John P. Blakeslee and Patrick Côté and Laura Ferrarese and Adrienne M. Juett and Simona Mei and Eric W. Peng},
journal= {arXiv preprint arXiv:astro-ph/0611237},
year = {2016}
}
备注
Accepted by Astrophysical Journal after minor changes, (this version also fixes improper display of Figure 3), 19 pages, 5 Color Figures (degraded), 6 B & W Figures: Full resolution paper available at http://www.astronomy.ohio-state.edu/~sivakoff/ACSVCS/ACS_GCLMXB_Optical.pdf