Searching for Excess Rotation Measures in Galaxy Clusters with the NVSS

Journal of astrophysics and astronomy

M. Johnston-Hollitt1¹  G. Grimwood¹ 

[1] Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand$$

关键词: Galaxy clusters;    magnetic fields.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

We present a statistical analysis of the rotation measure (RM) catalogue from the NVSS in search for a statistical excess of rotation measure through Abell clusters. After excluding the data known to be affected by the large-scale magnetic field of the Galaxy (𝑏 ≤ |30|), we consider RMs as a function of normalized Abell radius for 496 galaxy clusters. Despite that it is now well established that galaxy clusters contain magnetic fields, we find no evidence of an increase of the rotation measure for lines of sight toward Abell clusters. Additionally, we find no evidence for statistically different rotation measure values between cluster lines of sight and RMs up to 7 Abell radii from the cluster over that expected from the intrinsic variation of the NVSS dataset. We suggest this is the result of sparse spatial coverage of suitably polarized sources in the NVSS.

【 授权许可】

Unknown