arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0911.3785astro-ph.CO
收藏

邻近星系团中的螺旋状结构

Spiral-like structure in nearby clusters of galaxies

Tatiana F. Lagana, Felipe Andrade-Santos, Gastao B. Lima Neto

备注：
14 pages, 3 figures, accepted for publication in A&A (Nov 17, 2009)
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

X射线数据分析发现，星系团中心相当复杂的结构比预期的更常见。这些结构中的许多具有相似的形态，其表现出螺旋状的亚结构。目前还不清楚这些结构是如何形成或维持的。了解这些螺旋状特征的起源在一些集群的中心是这项工作的主要动机。我们分析了深\textit{Chandra}观测附近的15个星系团（0.01 $ < z < $ 0.06），并使用X射线温度和子结构图，以检测小功能的核心集群。我们在7个星团的中心检测到螺旋状特征：A85，A426，A496，Hydra A星团，半人马座，蛇夫座和A4059。这些模式是类似的集群合并与非零碰撞参量的数值流体动力学模拟中发现的。在我们样本的一些星团中，一个强射电源也占据了星团的内部区域，这表明两者之间可能存在联系。我们的研究表明，这些螺旋状结构可能是由离轴的小合并。由于这些特征出现在高密度区域，它们可能会限制来自中央星系的无线电发射，在某些情况下，产生不寻常的无线电形态。

英文摘要：

X-ray data analysis have found that fairly complex structures at cluster centres are more common than expected. Many of these structures have similar morphologies, which exhibit spiral-like substructure. It is not yet well known how these structures formed or are maintained. Understanding the origin of these spiral-like features at the centre of some clusters is the major motivation behind this work. We analyse deep \textit{Chandra} observations of 15 nearby galaxy clusters (0.01 $ < z < $ 0.06), and use X-ray temperature and substructure maps to detect small features at the cores of the clusters. We detect spiral-like features at the centre of 7 clusters: A85, A426, A496, Hydra A cluster, Centaurus, Ophiuchus, and A4059. These patterns are similar to those found in numerical hydrodynamic simulations of cluster mergers with non-zero impact parameter. In some clusters of our sample, a strong radio source also occupies the inner region of the cluster, which indicates a possible connection between the two. Our investigation implies that these spiral-like structures may be caused by off-axis minor mergers. Since these features occur in regions of high density, they may confine radio emission from the central galaxy producing, in some cases, unusual radio morphology.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑