The XMM-Newton serendipitous survey - IV. Optical identification of the XMM-Newton medium sensitivity survey (XMS)

	The XMM-Newton serendipitous survey - IV. Optical identification of the XMM-Newton medium sensitivity survey (XMS)
	Barcons, X; Carrera, FJ; Ceballos, MT; Page, MJ; Bussons-Gordo, J; Corral, A; Ebrero, J; Mateos, S; Tedds, JA; Watson, MG
刊名	ASTRONOMY & ASTROPHYSICS
	2007-12
卷号	476 期号:3 页码:1191-U35
关键词	X-rays : general X-rays : galaxies X-rays : stars galaxies : active
ISSN号	0004-6361
通讯作者	Barcons, X (reprint author), CSIC UC, Inst Fis Cantabria, Santander 39005, Spain.
产权排序	第二十一完成单位
英文摘要	Aims. X-ray sources at intermediate fluxes (a few x 10(-14) erg cm(-2) s(-1)) with a sky density of similar to 100 deg(-2) are responsible for a significant fraction of the cosmic X-ray background at various energies below 10 keV. The aim of this paper is to provide an unbiased and quantitative description of the X-ray source population at these fluxes and in various X-ray energy bands. Methods. We present the XMM-Newton Medium sensitivity Survey (XMS), including a total of 318 X-ray sources found among the serendipitous content of 25 XMM-Newton target fields. The XMS comprises four largely overlapping source samples selected at soft (0.5-2 keV), intermediate (0.5-4.5 keV), hard (2-10 keV) and ultra-hard (4.5-7.5 keV) bands, the first three of them being flux-limited. Results. We report on the optical identification of the XMS samples, complete to 85-95%. At the flux levels sampled by the XMS we find that the X-ray sky is largely dominated by Active Galactic Nuclei. The fraction of stars in soft X-ray selected samples is below 10%, and only a few per cent for hard selected samples. We find that the fraction of optically obscured objects in the AGN population stays constant at around 15-20% for soft and intermediate band selected X-ray sources, over 2 decades of flux. The fraction of obscured objects amongst the AGN population is larger (similar to 35-45%) in the hard or ultra-hard selected samples, and constant across a similarly wide flux range. The distribution in X-ray-to-optical flux ratio is a strong function of the selection band, with a larger fraction of sources with high values in hard selected samples. Sources with X-ray-to-optical flux ratios in excess of 10 are dominated by obscured AGN, but with a significant contribution from unobscured AGN.
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 ; CHANDRA MULTIWAVELENGTH PROJECT ; X-RAY SOURCES ; DEEP ROSAT SURVEY ; LOG S-RELATION ; HELLAS2XMM SURVEY ; SOURCE CATALOG ; LOCKMAN HOLE ; FOLLOW-UP ; FIELD
收录类别	SCI ; EI
原文出处	http://www.aanda.org/articles/aa/abs/2007/48/aa7606-07/aa7606-07.html
语种	英语
WOS记录号	WOS:000251507500014
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/4953]
专题	云南天文台_高能天体物理研究组
推荐引用方式 GB/T 7714	Barcons, X,Carrera, FJ,Ceballos, MT,et al. The XMM-Newton serendipitous survey - IV. Optical identification of the XMM-Newton medium sensitivity survey (XMS)[J]. ASTRONOMY & ASTROPHYSICS,2007,476(3):1191-U35.
APA	Barcons, X.,Carrera, FJ.,Ceballos, MT.,Page, MJ.,Bussons-Gordo, J.,...&Ziaeepour, H.(2007).The XMM-Newton serendipitous survey - IV. Optical identification of the XMM-Newton medium sensitivity survey (XMS).ASTRONOMY & ASTROPHYSICS,476(3),1191-U35.
MLA	Barcons, X,et al."The XMM-Newton serendipitous survey - IV. Optical identification of the XMM-Newton medium sensitivity survey (XMS)".ASTRONOMY & ASTROPHYSICS 476.3(2007):1191-U35.