Photometric and spectroscopic follow-up of optical counterparts of X-ray sources in the RasTyc sample

Antonio Frasca, Patrick Guillout, Rubens Freire-Ferrero +2

The cross-correlation between the ROSAT all-sky survey (~150000 sources) and the Tycho mission (~1000000 stars) catalogs has selected about 14000 stellar X-ray sources (RasTyc samp…