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The influence of magnetic fields on the Sunyaev Zel'dovich effect in clusters of galaxies

P. M. Koch·Ph. Jetzer·D. Puy
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Abstract

We study the influence of intracluster large scale magnetic fields on the thermal Sunyaev-Zel'dovich (SZ) effect. In a macroscopic approach we complete the hydrostatic equilibrium equation with the magnetic field pressure component. Comparing the resulting mass distribution with a standard one, we derive a new electron density profile. For a spherically symmetric cluster model, this new profile can be written as the product of a standard ($β$-) profile and a radius dependent function, close to unity, which takes into account the magnetic field strength. For non-cooling flow clusters we find that the observed magnetic field values can reduce the SZ signal by $\sim 10%$ with respect to the value estimated from X-ray observations and the $β$-model. If a cluster harbours a cooling flow, magnetic fields tend to weaken the cooling flow influence on the SZ-effect.

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P. M. Koch, Ph. Jetzer, D. Puy. 2002-09-18. The influence of magnetic fields on the Sunyaev Zel'dovich effect in clusters of galaxies. https://doi.org/10.1016/s1384-1076(02)00194-x

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