The ROSAT deep survey - II. Optical identification, photometry and spectra of X-ray sources in the Lockman field

被引：0

作者：

Schmidt, M

Hasinger, G

Gunn, J

Schneider, D

Burg, R

Giacconi, R

Lehmann, I

MacKenty, J

Trumper, J

Zamorani, G

机构：

[1] Inst Astrophys, D-14482 Potsdam, Germany

[2] CALTECH, Pasadena, CA 91125 USA

[3] Princeton Univ Observ, Princeton, NJ 08540 USA

[4] Penn State Univ, University Pk, PA 16802 USA

[5] Johns Hopkins Univ, Baltimore, MD 21218 USA

[6] European So Observ, D-85748 Garching, Germany

[7] Space Telescope Sci Inst, Baltimore, MD 21218 USA

[8] Max Planck Inst Extraterr Phys, D-85740 Garching, Germany

[9] Osservatorio Astron Bologna, I-40126 Bologna, Italy

[10] CNR, Ist Radioastron, I-40129 Bologna, Italy

来源：

ASTRONOMY & ASTROPHYSICS | 1998年 / 329卷 / 02期

关键词：

surveys; galaxies : active; quasars : emission lines; galaxies : Seyfert; X-rays : galaxies;

D O I：

暂无

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The ROSAT Deep Survey includes a complete sample of 50 X-ray sources with fluxes in the 0.5 - 2 keV band larger than 5.5 10(-15) erg cm(-2) s(-1) in the Lackman field (Hasinger et al., Paper I). We have obtained deep broad-band CCD images of the field and spectra of many optical objects near the positions of the X-ray sources. We define systematically the process leading to the optical identifications of the X-ray sources. For this purpose, we introduce five identification (ID) classes that characterize the process in each case. Among the 50 X-ray sources, we identify 39 AGNs, 3 groups of galaxies, 1 galaxy and 3 galactic stars. Four X-ray sources remain unidentified so far; two of these objects may have an unusually large ratio of X-ray to optical flux.

引用

页码：495 / 503

页数：9

共 31 条

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