论文标题
银河系中13个潮汐流的恒星密度的均匀建模
Uniform Modelling of the Stellar Density of Thirteen Tidal Streams within the Galactic Halo
论文作者
论文摘要
我们使用来自DES,贴花和Pan-Starrs的光度数据,将柔性恒星流密度模型拟合到银河系周围的13个流的集合。我们为每个流构建密度图,并沿每个流的长度表征它们的轨道在天空,宽度和距离模量曲线上。我们使用这些测量值来计算流的长度和总亮度,并识别子结构。几条流显示出突出的子结构,例如溪流宽,差距,溪流轨道的巨大偏差以及流密度的急剧变化。正如预期的那样,研究溪流作为人口,我们发现,带球簇祖细胞的流通常比患有矮星系祖细胞的河流狭窄,其中两个人群之间的流频率约为100 pc。我们还注意到,球状簇流的平均光度明显低于完整球形簇的典型光度。可能的解释是,观察到的球状簇流优先来自较低的光度和较低的密度簇。以此处介绍的统一方式进行的流测量结果将有助于更详细的流研究,例如识别候选流构件进行光谱式跟踪跟踪和出色的流动力学建模。
We present the results of fitting a flexible stellar stream density model to a collection of thirteen streams around the Milky Way, using photometric data from DES, DECaLS, and Pan-STARRS. We construct density maps for each stream and characterise their tracks on the sky, width, and distance modulus curves along the length of each stream. We use these measurements to compute lengths and total luminosities of streams and identify substructures. Several streams show prominent substructures, such as stream broadening, gaps, large deviations of stream tracks and sharp changes in stream densities. Examining the group of streams as a population, as expected we find that streams with globular cluster progenitors are typically narrower than those with dwarf galaxy progenitors, with streams around 100 pc wide showing overlap between the two populations. We also note the average luminosity of globular cluster streams is significantly lower than the typical luminosity of intact globular clusters. The likely explanation is that observed globular cluster streams preferentially come from lower luminosity and lower density clusters. The stream measurements done in a uniform manner presented here will be helpful for more detailed stream studies such as identifying candidate stream members for spectroscopic follow up and stellar stream dynamical modeling.