标题： 具有精细结构的五颗椭圆星系中的HI搜寻 显示英文标题

标题： A Search for HI in Five Ellipticals with Fine Structure

摘要： 我们报道了对五个早期星系的甚大阵列（VLA）氢原子谱线观测，这些星系因存在喷流、涟漪或其他光学“精细结构”而被归类为光学上异常。 在五个系统中的四个内检测到了氢原子（HI），但在只有一个案例中，这种气体与目标椭圆星系相关联。 在其他情况下，HI与附近的富含气体的盘状星系或矮星系相关联。 唯一的HI探测结果是对于NGC 7626，在其中我们初步探测到一个位于星系中心西南20到40千秒差距之间的HI云。 其起源尚不清楚。 我们未能检测到明显的潮汐HI特征，这表明如果这些精细结构的椭圆星系是盘状星系合并的遗迹，那么要么其前身缺乏气体，要么它们已经高度演化，任何气体潮汐特征已分散和/或转化为其他相态。 我们的目标系统都位于星系团或星系群中，似乎在这些环境中潮汐HI的存在时间比孤立合并遗迹的研究所暗示的要短。 显示英文摘要

摘要： We report on VLA HI spectral line observations of five early-type galaxies classified as optically peculiar due to the presence of jets, ripples or other optical "fine structure". We detect HI within the primary beam (30' HPBW) in four of the five systems. However, in only one case is this gas associated with the targeted elliptical galaxy. In the other cases the HI is associated with a nearby gas-rich disk or dwarf galaxy. The one HI detection is for NGC 7626, where we tentatively detect an HI cloud lying between 20 and 40 kpc southwest of the galaxy center. Its origin is unclear. Our failure to detect obvious tidal HI features suggests that if these fine-structure ellipticals are remnants of disk galaxy mergers, either the progenitors were gas poor, or they are well evolved and any gaseous tidal features have dispersed and/or been converted into other phases. Our targeted systems all reside in groups or clusters, and it seems likely that tidal HI is shorter lived in these environments than suggested by studies of more isolated merger remnants.