论文标题
XDCPJ0044.0-2033的BCG组装期间的多重AGN活性在z〜1.6
Multiple AGN activity during the BCG assembly of XDCPJ0044.0-2033 at z~1.6
论文作者
论文摘要
不受干扰的星系簇的特征是其中心位于其中心，即最亮的星系星系（BCG）。这些中央星系的形式仍在争论中。根据大多数模型，其组装的典型时期是Z〜1-2。我们对XDCPJ0044.0-2033（XDCP0044）的核心进行了详细的多波长分析，这是目前在RedShift Z〜1.6上闻名的最庞大，最密集的星系簇之一，其中央星系中的中央星系显示了与X-Ray Agn相比的高恒星形成。 Sinfoni J-，H-和KMOS YJ-，H-Bands光谱数据已被分析，以及F105W，F140W和F160W带中的深档案HST HST光度数据，Chandra X射线，Chandra X射线，无线电JVLA，1-2 GHz和Alma Band-6观察。在集群的中央区域（〜70x70 kpc^2）中，已经鉴定出和研究了2个相互作用星系系统（复杂的A和B），共有7个确认的群集成员。这些星系显示出扰动的形态，其中3个显示出AGN活性的迹象。特别是，在每个复合物的中心都发现了2型1型AGN（X射线均匀且高度积聚； Eddington的比率〜0.5），而在复杂A中发现了2型AGN。 3 AGN提供了到目前为止揭示的最接近的AGN三倍之一，最小值（最大）投影距离为〜10（40）kpc。 XDCP0044核心中高星形形成，合并特征和核活动的观察表明，所有这些过程都是塑造新生BCG的关键成分。根据我们的数据，XDCP0044可以形成一个典型的大型星系为10^12 msun，在〜2.5 Gyrs的时间范围内，托管2x10^8-10^9 msun的黑洞。
Undisturbed galaxy clusters are characterized by a massive and large elliptical galaxy at their center, i.e. the Brightest Cluster Galaxy (BCG). How these central galaxies form is still debated. According to most models, a typical epoch for their assembly is z~1-2. We have performed a detailed multi-wavelength analysis of the core of XDCPJ0044.0-2033 (XDCP0044), one of the most massive and densest galaxy clusters currently known at redshift z~1.6, whose central galaxy population shows high star formation compared to lower-z clusters and an X-ray AGN located close to its center. SINFONI J-, H- and KMOS YJ-, H- bands spectroscopic data have been analyzed, together with deep archival HST photometric data in F105W, F140W, and F160W bands, Chandra X-ray, radio JVLA data at 1-2 GHz, and ALMA band-6 observations. In the central region of the cluster (~70x70 kpc^2), 2 systems of interacting galaxies have been identified and studied (Complex A and B), with a total of 7 confirmed cluster members. These galaxies show perturbed morphologies and 3 of them show signs of AGN activity. In particular, 2 type-1 AGN with typical broad lines have been found at the center of each complex (both of them X-ray obscured and highly accreting; Eddington ratio ~0.5), while a type-2 AGN has been discovered in Complex A. The AGN at the center of Complex B is also detected in X-ray while the other 2 are spatially related to radio emission. The 3 AGN provide one of the closest AGN triple at z>1 revealed so far with a minimum(maximum) projected distance of ~10(40) kpc. The observation of high star formation, merger signatures and nuclear activity in the core of XDCP0044 suggests that all these processes are key ingredients in shaping the nascent BCG. According to our data, XDCP0044 could form a typical massive galaxy of 10^12 Msun, hosting a Black Hole of 2x10^8-10^9 Msun, in a time scale of the order of ~2.5 Gyrs.
