Dissecting the complex environment of a distant quasar with MUSE
Dissecting the complex environment of a distant quasar with MUSE
复制标题
DOI：
10.1093/mnras/stv1424
复制
发表时间：
2015-07
影响因子：
4.8
通讯作者：
K. Husband;M. Bremer;E. Stanway;M. Lehnert
中科院分区：
文献类型：
--
作者：
K. Husband;M. Bremer;E. Stanway;M. Lehnert
高红移类星体可以用来追踪大质量星系的早期成长，并且可能是由星系与星系之间的相互作用触发的。我们提供了一个这样的相互作用系统的多目标光谱探测器（MUSE）的科学验证数据，该系统包括已被充分研究的z = 3.2 PKS 1614 +051类星体，它的活动星系核同伴星系和类星体与其同伴之间的Ly α辐射物质桥。我们总共发现了四个伴星系（至少有两个星系是新发现的），其中三个位于类星体宿主可能的维里半径内，这表明该系统将在今天演变成一个巨大的椭圆星系。MUSE数据的质量足以将扩展的Ly α发射线分裂成窄的速度通道。在这些气体中，可以看到气体向三个相邻星系中的每一个延伸，这表明发射线气体起源于星系和类星体宿主之间的引力相互作用。这种气体的光电离源不太清楚，但可能由两个活动星系核主导。类星体的Ly α发射光谱是双峰的，可能是由于在类星体的系统红移处吸收了中性物质，并且由于没有阻尼翼，柱密度很低。活动星系核和桥的Ly α发射的光谱轮廓也与相同红移处的吸收一致，表明这种中性物质可能延伸超过50 kpc。中性物质在类星体的视线中被看到，并与之横切，我们看到类星体，它也照亮了发射线桥，这一事实表明类星体是各向同性辐射的，任何遮蔽的环面都很小。这些结果证明了MUSE在研究高红移相互作用系统动力学方面的能力。
High-redshift quasars can be used to trace the early growth of massive galaxies and may be triggered by galaxy–galaxy interactions. We present Multi-Object Spectroscopic Explorer (MUSE) science verification data on one such interacting system consisting of the well-studied z = 3.2 PKS1614+051 quasar, its AGN companion galaxy and bridge of material radiating in Ly α between the quasar and its companion. We find a total of four companion galaxies (at least two galaxies are new discoveries), three of which reside within the likely virial radius of the quasar host, suggesting that the system will evolve into a massive elliptical galaxy by the present day. The MUSE data are of sufficient quality to split the extended Ly α emission line into narrow velocity channels. In these the gas can be seen extending towards each of the three neighbouring galaxies suggesting that the emission-line gas originates in a gravitational interaction between the galaxies and the quasar host. The photoionization source of this gas is less clear but is probably dominated by the two AGN. The quasar's Ly α emission spectrum is double peaked, likely due to absorbing neutral material at the quasar's systemic redshift with a low column density as no damping wings are present. The spectral profiles of the AGN and bridge's Ly α emission are also consistent with absorption at the same redshift indicating that this neutral material may extend over >50 kpc. The fact that the neutral material is seen in the line of sight to the quasar and transverse to it, and the fact that we see the quasar and it also illuminates the emission-line bridge, suggests that the quasar radiates isotropically and any obscuring torus is small. These results demonstrate the power of MUSE for investigating the dynamics of interacting systems at high redshift.