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Effects of sub-mm and radio point sources on the recovery of Sunyaev-Zeldovich galaxy cluster parameters

Lloyd Knox·Gil Holder·Sarah Church
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Abstract

Observations of clusters in the 30 to 350 GHz range can in principle be used to determine a galaxy cluster's Comptonization parameter, y, peculiar velocity, v and gas temperature, T_e via the dependence of the kinetic and thermal Sunyaev-Zeldovich (SZ) effects on these parameters. Despite the significant contamination expected from thermal emission by dust in high-redshift galaxies, we find that the simultaneous determination of optical depth (tau), v and T_e is possible from observations with sensitivity of a few uK in three or more bands with arc minute resolution. After allowing for realistic levels of contamination by dusty galaxies and primary CMB anisotropy, we find that simultaneous determinations of velocities to an accuracy of better than 200 km/s and temperatures to roughly keV accuracy should be possible in the near future. We study how errors change as a function of cluster properties (angular core radius and gas temperature) and experimental parameters (observing time, angular resolution and observing frequencies). Contaminating synchrotron emission from cluster galaxies will probably not be a major contaminant of peculiar velocity measurements.

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Lloyd Knox, Gil Holder, Sarah Church. 2004-02-23. Effects of sub-mm and radio point sources on the recovery of Sunyaev-Zeldovich galaxy cluster parameters. https://doi.org/10.1086/422447

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