论文标题
浸入可压缩银河潮汐场中的均匀密度恒星簇的世俗演化
The secular evolution of a uniform density star cluster immersed in a compressible galactic tidal field
论文作者
论文摘要
核恒星簇在星系中心很常见。我们认为，他们假定为球形簇的祖细胞可能在其他地方形成，迁移到并组装在其目前的位置附近的可能性。这种情况的主要挑战是球形群集是否可以承受其宿主星系的潮汐场。我们的分析表明，如果背景电位的质量密度分布相对较浅，例如在某些具有相对平坦的表面亮度曲线的星系中，星系中心附近的潮汐场可能显示出能够压缩而不是在与常规定义的“ Tidal Disprimion Dismultion radius”（$ R_ r_ t $ r_ t $ r_ t $ r_ $ r_ $ r_ $ r_ t）中距离距离小得多。为此，我们采用了先前构造的形式主义，并考虑具有均匀质量密度分布的星形簇的世俗演变。我们通过分析求解银河中心中恒星质量密度接近均匀分布的限制的世俗方程。我们的模型表明，星团可能会走上距离$ r_t $的距离，而不会中断，从而有可能导致核簇的形成。但是，需要适当的数值N体模拟来确认我们的分析结果。
Nuclear stellar clusters are common in the center of galaxies. We consider the possibility that their progenitors assumed to be globular clusters may have formed elsewhere, migrated to and assembled near their present location. The main challenge for this scenario is whether globular clusters can withstand the tidal field of their host galaxies. Our analysis suggests that provided the mass-density distribution of background potential is relatively shallow, as in some galaxies with relatively flat surface brightness profiles, the tidal field near the center of galaxies may be shown to be able to compress rather than disrupt a globular cluster at a distance from the center much smaller than the conventionally defined `tidal disruption radius', $r_t$. To do so, we adopt a previously constructed formalism and consider the secular evolution of star clusters with a homogeneous mass density distribution. We analytically solve the secular equations in the limit that the mass density of stars in the galactic center approaches a uniform distribution. Our model indicates that a star cluster could travel to distances much smaller than $r_t$ without disruption, thus potentially contributing to the formation of the nuclear cluster. However, appropriate numerical N-body simulations are needed to confirm our analytic findings.
