On the Kinematic Morphology around Halos [CEA]

http://arxiv.org/abs/2209.06488


In this paper, we report an interesting kinematic phenomenon around the halos’ edge related to the `splashback’ radius. After the shell-crossing, cosmic flow exhibits various rotational morphologies via stream-mixing. Vorticity is generated in a particular way that coincides with the large-scale structure. Notably, one specific flow morphology concentrates around halos. A detailed examination reveals a sharp change in the logarithmic derivative of its volume fraction at the location of the splashback radius defined as the outermost caustic structure. Such a feature encodes valuable phase space information and provides a new perspective on understanding the dynamical evolution of halos. As a volume-weighted quantity, the profile of flow morphology is purely kinematic. Unlike other related studies, the rotational flow morphologies capture the anisotropic phase structure in the multi-stream region.

Read this paper on arXiv…

X. Luo, X. Xu and X. Wang
Thu, 15 Sep 22
6/67

Comments: submitted to MNRAS, comments welcome