IDENTIFICATION OF SOFT HIGH GALACTIC LATITUDE RASS X-RAY SOURCES - I - A COMPLETE COUNT-RATE LIMITED SAMPLE

Citation
Hc. Thomas et al., IDENTIFICATION OF SOFT HIGH GALACTIC LATITUDE RASS X-RAY SOURCES - I - A COMPLETE COUNT-RATE LIMITED SAMPLE, Astronomy and astrophysics (Berlin), 335(2), 1998, pp. 467-478
Citations number
62
Categorie Soggetti
Astronomy & Astrophysics
ISSN journal
00046361
Volume
335
Issue
2
Year of publication
1998
Pages
467 - 478
Database
ISI
SICI code
0004-6361(1998)335:2<467:IOSHGL>2.0.ZU;2-T
Abstract
We present a summary of spectroscopic identifications for a complete s ample of bright soft high galactic latitude X-ray sources drawn from t he ROSAT All-Sky Survey which have PSPC count-rates CR > 0.5 cts s(-1) and hardness ratios HR1 < 0. Of a total of 397 sources, 270 had catal ogued counterparts although most of these were not previously known as X-ray sources; of the remaining 127 sources neither X-ray nor optical properties were previously known. Of the whole sample of very soft X- ray sources 155 were also discovered by the Wide-Field-Camera on board ROSAT. We present spectroscopic identifications of 108 sources and ot her identifications for further 18 sources; 1 source remains unidentif ied so far. In practically all cases a unique optical counterpart exis ts facilitating identification. The largest source classes are AGN, ma gnetic cataclysmic variables, and hot white dwarfs.