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DOI QR Code

A CLUSTER SURVEY AROUND THE UNIDENTIFIED EGRET SOURCES

  • KAWASAKI WATARU (Institute of Astronomy and Astrophysics, Academia Sinica) ;
  • TOTANI TOMONORI (Department of Astronomy, Kyoto University)
  • Published : 2005.06.01

Abstract

Based on optical galaxy data, we executed a systematic search for galaxy clusters around the 15 steady unidentified EGRET GeV gamma-ray sources in high Galactic-latitude sky ([b] > $30^{\circ}$). We found a strong correlation with 3.7$\sigma$ level between close cluster pairs (merging cluster candidates) and the unidentified EGRET sources, though, in contrast, no correlation with single clusters. This result implies that merging clusters of galaxies are a possible candidate for the origin of high galactic-latitude, steady unidentified EGRET gamma-ray sources.

Keywords

galaxies: clusters: general;gamma rays: unidentified sources;large-scale structure of universe;surveys

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