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arXiv · 0803.2168

Multi-Band Analysis of Abell 2255

M. Hudaverdi·E. N. Ercan·A. Mert-Ankar·F. Gok·E. Aktekin·G. I. Gun·B. Ugras·T. Guver·H. Kunieda
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Abstract

We analyzed the data for the nearby cluster of galaxies Abell 2255 from archival XMM-Newton observations in order to search for the properties of X-ray point like structures in the outskirts. 11 point-like X-ray emission is detected. Detected X-ray sources are then observed with the 1.5 meter RTT-150 at Turkish National Observatory for possible optical counterparts. The cluster field is covered through 5 ANDOR photometer pointings. 3 sources have no optical follow-ups. 2 QSOs and 1 star are observed from the field. For 4 sources we have obtained the corresponding redhifts. The cumulative log(N)-log(S) is studied and the cluster source number is calculated to be 4 times higher than the field at Fx~10E-13 ergs cm-2 s-1. This phenomenon is interpreted as increased galaxy activity as they first encounter high density ICM environment at the cluster outskirt. We suggest that X-ray emission is triggered by either increased accretion onto LMXBs, fueling of AGNs and/or awakening of BHs.

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M. Hudaverdi, E. N. Ercan, A. Mert-Ankar, F. Gok, E. Aktekin, G. I. Gun, B. Ugras, T. Guver, H. Kunieda. 2008-03-14. Multi-Band Analysis of Abell 2255. https://arxiv.org/abs/0803.2168

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