Correlation of the magnetic field and the intra-cluster gas density in galaxy clusters

Citation
K. Dolag et al., Correlation of the magnetic field and the intra-cluster gas density in galaxy clusters, ASTRON ASTR, 378(3), 2001, pp. 777-786
Citations number
47
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY & ASTROPHYSICS
ISSN journal
1432-0746 → ACNP
Volume
378
Issue
3
Year of publication
2001
Pages
777 - 786
Database
ISI
SICI code
1432-0746(200111)378:3<777:COTMFA>2.0.ZU;2-Y
Abstract
We present a correlation between X-ray surface brightness and Faraday rotat ion measure in galaxy clusters, both, from radio and X-ray observations as well as from modeling of the intra-cluster medium. The observed correlation rules out a magnetic field of constant strength throughout the cluster. Co smological, magnetohydrodynamic simulations of galaxy clusters are used to show that for a magnetic field of cosmic origin this correlation is expecte d and excellently reproduces the observations showing that the rms scatter of the Faraday rotation increases linearly with the X-ray surface brightnes s. From the correlation between the observable quantities, rotation measure and X-ray surface brightness, we infer a relation between the physical qua ntities: magnetic field and gas density. For the best available observation s, those of A119, we find B proportional to n(e)(0.9).