中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
The XMM-SSC survey of hard-spectrum XMM-Newton sources - I. Optically bright sources

文献类型:期刊论文

作者Page, M. J.1; Lehmann, I.2; Boller, Th.2; Watson, M. G.3; Dwelly, T.1,4; Hess, S.2; Matute, I.2; Loaring, N. S.1,5; Rosen, S.1; Ziaeepour, H.1
刊名MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
出版日期2007-07-11
卷号378期号:4页码:1335-1355
ISSN号0035-8711
关键词galaxies : active X-rays : galaxies
通讯作者Page, MJ (reprint author), Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England.
产权排序第十完成单位
英文摘要We present optical and X-ray data for a sample of serendipitous XMM-Newton sources that are selected to have 0.5-2 versus 2-4.5 keV X-ray hardness ratios which are harder than the X-ray background. The sources have 2-4.5 keV X-ray flux , and in this paper we examine a subsample of 42 optically bright (r < 21)> sources; this subsample is 100 per cent spectroscopically identified. All but one of the optical counterparts are extragalactic, and we argue that the single exception, a Galactic M star, is probably a coincidental association rather than the correct identification of the X-ray source. The X-ray spectra of all the sources are consistent with heavily absorbed power laws (21.8 < log N(H) < 23.4), and all of them, including the two sources with 2-10 keV intrinsic luminosities of < 10(42) erg s(-1), appear to be absorbed active galactic nuclei (AGN). The majority of the sources show only narrow emission lines in their optical spectra, implying that they are type 2 AGN. Three sources have 2-10 keV luminosities of > 10(44) erg s(-1), and two of these sources have optical spectra which are dominated by narrow emission lines, that is, are type 2 QSOs. Only a small fraction of the sources (7/42) show broad optical emission lines, and all of these have N(H) < 10(23) cm(-2). This implies that ratios of X-ray absorption to optical/ultraviolet extinction equivalent to > 100 times the Galactic gas-to-dust ratio are rare in AGN absorbers (at most a few per cent of the population), and may be restricted to broad absorption line QSOs. Seven objects appear to have an additional soft X-ray component in addition to the heavily absorbed power law; all seven are narrow emission-line objects with z < 0.3 and 2-10 keV intrinsic luminosities < 10(43) erg s(-1). We consider the implications of our results in the light of the AGN unified scheme. We find that the soft components in narrow-line objects are consistent with the unified scheme provided that > 4 per cent of broad-line AGN (BLAGN) have ionized absorbers that attenuate their soft X-ray flux by > 50 per cent. In at least one of the X-ray-absorbed BLAGN in our sample the X-ray spectrum requires an ionized absorber, consistent with this picture.
学科主题Astronomy & Astrophysics
WOS标题词Science & Technology ; Physical Sciences
类目[WOS]Astronomy & Astrophysics
研究领域[WOS]Astronomy & Astrophysics
关键词[WOS]ACTIVE GALACTIC NUCLEI ; X-RAY-SPECTRA ; MEDIUM-SENSITIVITY SURVEY ; DEEP FIELD-SOUTH ; ULTRALUMINOUS INFRARED GALAXIES ; REFLECTION GRATING SPECTROMETER ; QUASI-STELLAR OBJECTS ; LUMINOSITY FUNCTION ; HELLAS2XMM SURVEY ; ASCA OBSERVATIONS
收录类别SCI
原文出处http://mnras.oxfordjournals.org/content/378/4/1335
语种英语
WOS记录号WOS:000247667900012
源URL[http://ir.ynao.ac.cn/handle/114a53/9364]  
专题云南天文台_高能天体物理研究组
作者单位1.Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT
2.Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse, Postfach 1312, 85741 Garching, Germany
3.Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH
4.School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ
5.South African Astronomical Observatory, Observatory, 7935 Cape Town, South Africa
6.Astrophysikalisches Institut Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany
7.Instituto de Física de Cantabria (CSIC – Universidad de Cantabria), 39005 Santander, Spain
8.INAF – Osservatorio Astronomico di Brera, via Brera 28, I-20121 Milano, Italy
9.University of Cambridge, Institute of Astronomy, Madingley Road, Cambridge CB3 0HA
10.National Astronomical Observatory of China/Yunnan Observatory, Kunming 650011, PO Box 110, Yunnan, China
推荐引用方式
GB/T 7714
Page, M. J.,Lehmann, I.,Boller, Th.,et al. The XMM-SSC survey of hard-spectrum XMM-Newton sources - I. Optically bright sources[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2007,378(4):1335-1355.
APA Page, M. J..,Lehmann, I..,Boller, Th..,Watson, M. G..,Dwelly, T..,...&Yuan WM.(2007).The XMM-SSC survey of hard-spectrum XMM-Newton sources - I. Optically bright sources.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,378(4),1335-1355.
MLA Page, M. J.,et al."The XMM-SSC survey of hard-spectrum XMM-Newton sources - I. Optically bright sources".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 378.4(2007):1335-1355.

入库方式: OAI收割

来源:云南天文台

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。