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Probing the Evolution of Gas Mass Fraction with Sunyaev-Zel'dovich Effect

Subhabrata Majumdar
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Abstract

Study of the primary anisotropies of the Cosmic Microwave Background (CMB) can be used to determine the cosmological parameters to a very high precision. The power spectrum of the secondary CMB anisotropies due to the thermal Sunyaev-Zel'dovich Effect (SZE) by clusters of galaxies, can then be studied, to constrain more cluster specific properties (like gas mass). We show the SZE power spectrum from clusters to be a sensitive probe of any possible evolution (or constancy) of the gas mass fraction. The position of the peak of the SZE power spectrum is a strong discriminatory signature of different gas mass fraction evolution models. For example, for a flat universe, there can be a difference in the $l$ values (of the peak) of {\it as much as 3000} between a constant gas mass fraction model and an evolutionary one. Moreover, observational determination of power spectrum, from blank sky surveys, is devoid of any selection effects that can possibly affect targeted X-ray or radio studies of gas mass fractions in galaxy clusters.

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Subhabrata Majumdar. 2001-02-25. Probing the Evolution of Gas Mass Fraction with Sunyaev-Zel'dovich Effect. https://doi.org/10.1086/323159

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