论文标题
处女座集群的星系光学变异性：环境影响的新示踪剂对星系的影响
Galaxy Optical Variability of Virgo Cluster: New Tracer for Environmental Influences on Galaxies
论文作者
论文摘要
我们使用palomar瞬态工厂数据研究了星系的光学变异性与处女座集群中心的距离之间的关系。我们定义了星系亮度的标准偏差与标准偏差的平均值之间的比率，以衡量星系的光学变异性。具有230263观测值的814个处女座星系的样本显示，随着簇距离的增加，光学变异性的单调降低趋势。集群内部的可变性水平比外部水平高3.2 $σ$。我们使用线性函数拟合可变性，并发现数据拒绝独立于距离的模型。我们检查了217个背景星系以进行比较，并发现星系可变性没有明显的趋势。我们通过重建每个星系的亮度来评估与蒙特卡洛模拟的关系。该模拟显示了成员星系变异性的单调减少关系和背景星系的距离独立关系。我们的结果与冷气向内流动的理论一致，簇中心燃料AGN活性。这项工作是使用光学变异性来研究星系演化与其环境之间关系的新实现。
We investigate the relationship between the optical variability of galaxies and their distances from the centre of the Virgo Cluster using Palomar Transient Factory data. We define the ratio between the standard deviation of the galaxy brightness and the mean value of the standard deviation as a measure of a galaxy's optical variability. A sample of 814 Virgo galaxies with 230263 observations shows a monotonically decreasing trend of optical variability with increasing clustercentric distance. The variability level inside the cluster is 3.2$σ$ higher than the level outside. We fit the variability with a linear function and find that the data reject a distance-independent model. We examine 217 background galaxies for comparison and find no significant trend in galaxy variability. We assess the relation with Monte Carlo simulation by rebuilding the brightness of each galaxy. The simulation shows a monotonically decreasing relation for member galaxy variability and a distance-independent relation for background galaxies. Our result is consistent with the theory that the cold gas flowing inwards the cluster centre fuels AGN activity. This work is a new implementation of the method using optical variability to investigate the relation between galaxies evolution and their environment.
