论文标题
FGC 1287及其神秘的250 kpc Long Hi尾巴在Abell 1367的郊区
FGC 1287 and its enigmatic 250 kpc long HI tail in the outskirts of Abell 1367
论文作者
论文摘要
We present HI and radio continuum, narrow-band H$α$ imaging, IFU spectroscopy, and X-ray observations of the FGC 1287 triplet projected $\sim$ 1.8 Mpc west of the galaxy cluster Abell 1367. One triplet member, FGC 1287, displays an exceptionally long, 250 kpc HI tail and an unperturbed stellar disk which are the typical signatures of ram压力剥离(RPS)。为了生成可检测的RPS签名,存在具有足够密度的集群内培养基(ICM)/组内培养基(IGM),相对于ICM/IgM,以现实速度产生RPS是前提条件。但是,XMM-Newton的观察结果无法检测到三重态的X射线发射,这意味着如果存在热的ICM/Igm,其密度为N $ {_ E} $,小于2.6 $ \ times $ 10 $^{ - 5} $^{ - 5} $ CM $ $ $^{ - 3} $。此处介绍的高分辨率VLA HI数据显示,FGC 1287的HI磁盘已被截断,并且明显扭曲了,而HI尾巴则是块状的。 TNG H $α$ Imaging确定了在FGC 1287的磁盘20 kpc内投射的三个星团,并带有VIMOS-IFU数据,证实了其中两个是与尾部中的Hi团块相对的。三胞胎的HI运动学以及H $α$和无线电连续成像表明,相互作用可能在FGC 1287的磁盘中增强了恒星的形成,但不能容易地说明长HI尾巴的起源。我们考虑了几种可能与ICM/IGM X射线发射的未检测来调和RP的情况,但这些都没有明确地解释了长HI尾巴的起源。
We present HI and radio continuum, narrow-band H$α$ imaging, IFU spectroscopy, and X-ray observations of the FGC 1287 triplet projected $\sim$ 1.8 Mpc west of the galaxy cluster Abell 1367. One triplet member, FGC 1287, displays an exceptionally long, 250 kpc HI tail and an unperturbed stellar disk which are the typical signatures of ram pressure stripping (RPS). To generate detectable RPS signatures the presence of an Intra-cluster medium (ICM)/intra-group medium (IGM) with sufficient density to produce RPS at a realistic velocity relative to the ICM/IGM is a prerequisite. However, XMM-Newton observations were not able to detect X-ray emission from the triplet, implying that if a hot ICM/IGM is present, its density, n${_e}$, is less than 2.6 $\times$ 10$^{-5}$ cm$^{-3}$. Higher-resolution VLA HI data presented here show FGC 1287's HI disk is truncated and significantly warped whereas the HI tail is clumpy. TNG H$α$ imaging identified three star forming clumps projected within 20 kpc of FGC 1287's disk, with VIMOS-IFU data confirming two of these are counterparts to HI clumps in the tail. The triplet's HI kinematics, together with H$α$ and radio continuum imaging suggests an interaction may have enhanced star formation in FGC 1287's disk, but cannot readily account for the origin of the long HI tail. We consider several scenarios which might reconcile RPS with the non-detection of ICM/IGM X-ray emission but none of these unambiguously explains the origin of the long HI tail.