COSMOS X射线星系群的Chandra中心:中心主导与偏移最亮群星系在恒星性质上的差异
星系天体物理
2019-10-21 v1
摘要
我们利用XMM-Newton与Chandra天文台所有可用的X射线观测,在约2平方度的COSMOS天区中展示了搜寻星系团与星系群的结果。我们达到– keV波段的X射线通量极限,并利用COSMOS的多波段测光红移与总光谱红移星表,识别出247个红移范围、的X射线星系群。星系群的X射线中心由高分辨率Chandra成像确定。我们研究了最亮群星系(BGGs)相对晕X射线中心的偏移与群性质之间的关系,并与半解析模型及流体动力学模拟的预测比较。我们发现BGG偏移随晕质量增大而减小、随红移降低而减小,对X射线通量与SNR无强依赖。我们展示BGG偏移随星等间隙增大而减小,且无显著红移依赖趋势。观测中BGG的恒星质量相比模型预测覆盖更宽动态范围。在,中心主导BGG比大偏移BGG质量高出至多0.3dex,与模型预测一致。在固定晕质量下,观测与预测的低偏移及大偏移BGG恒星质量的对数正态散度均为dex。
引用
@article{arxiv.1812.01604,
title = {Chandra centres for COSMOS X-ray galaxy groups: Differences in stellar properties between central dominant and offset brightest group galaxies},
author = {Ghassem Gozaliasl and Alexis Finoguenov and Masayuki Tanaka and Klaus Dolag and Francesco Montanari and Charles C. Kirkpatrick and Eleni Vardoulaki and Habib G. Khosroshahi and Mara Salvato and Clotilde Laigle and Henry J. McCracken and Olivier Ilbert and Nico Cappelluti and Emanuele Daddi and Guenther Hasinger and Peter Capak and Nick Z. Scoville and Sune Toft and Francesca Civano and Richard E. Griffiths and Michael Balogh and Yanxia Li and Jussi Ahoranta and Simona Mei and Angela Iovino and Bruno M. B. Henriques and Ghazaleh Erfanianfar},
journal= {arXiv preprint arXiv:1812.01604},
year = {2019}
}
备注
Accepted 2018 November 16 (MNRAS)