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arXiv · 0903.1392

A Search for X-Ray Reionization Signatures from Cross-Correlation of Wmap and ROSAT Rass Data

Quan Guo·Xiang-Ping Wu·HaiGuang Xu·JunHua Gu
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Abstract

We present an observational search for the possible correlation between cosmic microwave background (CMB) polarization map and soft X-ray background (SXRB) based on the ROSAT All-sky Survey (RASS) archive and WMAP five-year observations. This is motivated by the fact that some of the CMB polarization may arise from the scattering of CMB photons due to the free electrons generated by X-ray heating sources in the epoch of reionization. Detection of such a correlation allows one to study the role of X-ray heating in the process of reionization. However, the cross angular power spectrum of the CMB polarization and SXRB maps constructed from ROSAT RASS and WMAP five-year maps is consistent with no correlation. We attribute this negative detection to both the extremely weak signals and large instrumental noises. While a future search is needed with high sensitivity instruments for both CMB polarization and soft X-ray photons, our current results can still be used as a useful constraint on the effect of X-ray heating in the epoch of reionization.

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Quan Guo, Xiang-Ping Wu, HaiGuang Xu, JunHua Gu. 2009-03-09. A Search for X-Ray Reionization Signatures from Cross-Correlation of Wmap and ROSAT Rass Data. https://doi.org/10.1088/0004-637x%2F693%2F1%2F1000

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