论文标题

淡淡而褪色的尾巴:处女座星系中剥离的HI气体的命运

Faint and fading tails : the fate of stripped HI gas in Virgo cluster galaxies

论文作者

Taylor, Rhys, Köppen, Joachim, Jáchym, Pavel, Minchin, Robert, Palouš, Jan, Wünsch, Richard

论文摘要

尽管已知处女座群集中的许多星系损失了大量的HI气体,但只有大约十二个特征才知道HI在其母星系之外显着延伸。先前的数值模拟预测,通过RAM压力剥离去除的HI应具有远远超过观察性调查的灵敏度限制的柱密度。我们构建了一个简单的模型,以尝试量化我们可能期望检测到多少流的流。这说明了溪流在位置和速度空间中的预期随机方向以及预期的流长度和剥离HI的质量。使用来自Arecibo Galaxy环境调查的档案数据,我们搜索以前可能在较早分析中遗漏的流。我们报告了对十个流的自信检测以及其他十六个不确定的检测。我们表明,我们的分析预测应积极损失气体,但是溪流的质量通常远低于其母星系中缺失的HI量,这意味着相位变化和/或分散会使气体无法检测到。通过估计轨道时间尺度,我们估计1-10 msolar/yr的溶解速率能够解释几个长,大量流的存在以及较短,较小的较少特征的存在。

Although many galaxies in the Virgo cluster are known to have lost significant amounts of HI gas, only about a dozen features are known where the HI extends significantly outside its parent galaxy. Previous numerical simulations have predicted that HI removed by ram pressure stripping should have column densities far in excess of the sensitivity limits of observational surveys. We construct a simple model to try and quantify how many streams we might expect to detect. This accounts for the expected random orientation of the streams in position and velocity space as well as the expected stream length and mass of stripped HI. Using archival data from the Arecibo Galaxy Environment Survey, we search for any streams which might previously have been missed in earlier analyses. We report the confident detection of ten streams as well as sixteen other less sure detections. We show that these well-match our analytic predictions for which galaxies should be actively losing gas, however the mass of the streams is typically far below the amount of missing HI in their parent galaxies, implying that a phase change and/or dispersal renders the gas undetectable. By estimating the orbital timescales we estimate that dissolution rates of 1-10 Msolar/yr are able to explain both the presence of a few long, massive streams and the greater number of shorter, less massive features.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源