标题： 星团系统的动力学演化 I. 室女座星系团中 NGC 1404 的情况 显示英文标题

标题： Dynamical evolution of globular cluster systems in clusters of galaxies I. The case of NGC 1404 in the Fornax cluster

摘要： 我们通过数值模拟研究了球状星团（GCs）的潮汐剥离和吸积现象。特别是，我们将注意力集中在创建能够模拟Fornax星团中NGC 1404和NGC 1399球状星团系统的模型上，它们分别拥有贫乏（特定频率$S_{\rm N}$ $\sim$ 2）和丰富（$S_{\rm N}$ $\sim$ 10）的球状星团系统。我们最初在模拟中为NGC 1404赋予了典型$S_{\rm N}$（$\sim$5）的椭圆星系属性，并发现如果它的轨道高度偏心（偏心率$>$0.5），并且其初始球状星团系统的尺度长度约为自身有效半径的两倍，那么它的球状星团系统只能通过剥离减少到目前观测到的数量。这些被剥离的球状星团可以被认为形成了一个环绕Fornax星团中心的“潮汐流”（即星团内球状星团ICGCs），其中许多在成像研究中会被归类为NGC 1399的一部分。这些球状星团的物理特性（例如数量、径向分布）取决于NGC 1404中球状星团的轨道和初始分布。 我们的模拟还预测了一个趋势，即随着星团中心距离的增加，$S_{\rm N}$会上升——对于这一趋势，在Fornax星团中有一些观测支持。 显示英文摘要

摘要： We investigate, via numerical simulations, the tidal stripping and accretion of globular clusters (GCs). In particular, we focus on creating models that simulate the situation for the GC systems of NGC 1404 and NGC 1399 in the Fornax cluster, which have poor (specific frequency $S_{\rm N}$ $\sim$ 2) and rich ($S_{\rm N}$ $\sim$ 10) GC systems respectively. We initially assign NGC 1404 in our simulation a typical $S_{\rm N}$ ($\sim$ 5) for cluster ellipticals, and find that its GC system can only be reduced through stripping to the presently observed value, if its orbit is highly eccentric (with orbital eccentricity of $>$ 0.5) and if the initial scale length of the GCs system is about twice as large as the effective radius of NGC 1404 itself. These stripped GCs can be said to have formed a `tidal stream' of intracluster globular clusters (ICGCs) orbiting the centre of Fornax cluster (many of which would be assigned to NGC 1399 in an imaging study). The physical properties of these GCs (e.g., number, radial distribution) depend on the orbit and initial distribution of GCs in NGC 1404. Our simulations also predict a trend for $S_{\rm N}$ to rise with increasing clustercentric distance - a trend for which there is some observational support in the Fornax cluster.