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arXiv · 1208.4105

The nature of the unresolved extragalactic soft CXB

N. Cappelluti·P. Ranalli·M. Roncarelli·P. Arevalo·G. Zamorani A. Comastri·R. Gilli·E. Rovilos·C. Vignali·V. Allevato·A. Finoguenov·T. Miyaji·F. Nicastro·I. Georgantopoulos·A. Kashlinsky
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Abstract

In this paper we investigate the power spectrum of the unresolved 0.5-2 keV CXB with deep Chandra 4 Ms observations in the CDFS. We measured a signal which, on scales >30", is significantly higher than the Shot-Noise and is increasing with the angular scale. We interpreted this signal as the joint contribution of clustered undetected sources like AGN, Galaxies and Inter-Galactic-Medium (IGM). The power of unresolved cosmic sources fluctuations accounts for \sim 12% of the 0.5-2 keV extragalactic CXB. Overall, our modeling predicts that \sim 20% of the unresolved CXB flux is made by low luminosity AGN, \sim 25% by galaxies and \sim 55% by the IGM (Inter Galactic Medium). We do not find any direct evidence of the so called Warm Hot Intergalactic Medium (i.e. matter with 10^5K 7.5 and compared it with SMBH evolution models.

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N. Cappelluti, P. Ranalli, M. Roncarelli, P. Arevalo, G. Zamorani A. Comastri, R. Gilli, E. Rovilos, C. Vignali, V. Allevato, A. Finoguenov, T. Miyaji, F. Nicastro, I. Georgantopoulos, A. Kashlinsky. 2012-08-20. The nature of the unresolved extragalactic soft CXB. https://doi.org/10.1111/j.1365-2966.2012.21867.x

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