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Deep ROSAT Surveys & the contribution of AGNs to the soft X-ray background

Lehmann, I. and Hasinger, G. and Schmidt, M. and Gunn, J. E. and Schneider, D. P. and Giacconi, R. and McCaughrean, M. and Trümper, J. and Zamorani, G. (2001) Deep ROSAT Surveys & the contribution of AGNs to the soft X-ray background. In: X-ray astronomy: stellar endpoints, AGN, and the diffuse x-ray background. AIP Conference Proceedings. No.599. American Institute of Physics , Melville, N.Y., pp. 189-198. ISBN 0-7354-0043-1.

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The ROSAT Deep Surveys in the Lockman Hole have revealed that AGNs are the main contributors (~75%) to the soft X-ray background in the 1–2 keV band. Using new optical/infrared and radio observations we have obtained a nearly complete identification (93%) of the 91 X-ray sources down to a limiting flux of 1.2·10^(–15) erg cm^(–2) s^(–1) in the 0.5–2.0 keV band. We present the optical colors and the emission line properties of our AGNs in comparison with other X-ray selected AGN samples. Furthermore we discuss the fraction of red AGNs found in the ROSAT Deep Surveys. From the ROSAT Deep Surveys we see no evidence for a new class of X-ray bright galaxies, which significantly contributes to the soft X-ray background.

Item Type:Book Section
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Hasinger, G.0000-0002-0797-0646
Additional Information:© 2001 American Institute of Physics. Issue Date: 5 December 2001. We acknowledge the support in part by NASA grants NAG5-1531 (M.S.), NAG8-794, NAG5-1649, and NAGW-2508 (R.G.), and NSF grant AST-9509919 (D.S.). G.H. acknowledges the grant FKZ 50 OR 9908 0 by the Deutsches Zebtrum fur Luftund Raumfahrt e.V. (DLR). G.Z. acknowledges partial support by the Italian Space Agency (ASI) under contract ARS-96-70 and the Italian Ministry for University and Research (MURST) under grant Cofin 98-02-32.
Funding AgencyGrant Number
Deutsches Zentrum für Luft und Raumfahrt (DLR)FKZ 50 OR 9908
Agenzia Spaziale Italiana (ASI)ARS-96-70
Ministero dell'università e della ricerca scientifica e tecnologica (MURST)Cofin 98-02 32
Subject Keywords:galactic nuclei, X-ray sources (astronomical), cosmic background radiation, astronomical atlases, astronomical catalogues. Surveys-galaxies: active-Galaxies: Seyferts-quasars: emission lines-X-rays: galaxies.
Series Name:AIP Conference Proceedings
Issue or Number:599
Classification Code:PACS: 98.62.Js; 98.70.Qy; 98.70.Vc; 95.80.+p
Record Number:CaltechAUTHORS:20111118-092145577
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Official Citation:Deep ROSAT Surveys & the contribution of AGNs to the soft X-ray background I. Lehmann, G. Hasinger, M. Schmidt, J. E. Gunn, D. P. Schneider, R. Giacconi, M. McCaughrean, J. Trumper, and G. Zamorani, AIP Conf. Proc. 599, 189 (2001), DOI:10.1063/1.1434632
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:27849
Deposited By: Ruth Sustaita
Deposited On:21 Nov 2011 16:03
Last Modified:09 Nov 2021 16:52

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