... By undertaking a spectral and photometric investiґ gation of the central part of the bright elliptical galaxy NGC 759, we have found an optical counterpart for the circumnuclear molecular gas ring with the radius of # 3 ## (# 1 kpc) which was earlier reported by Wiklind et al. ... 2 Fig. ... More likely, this ring may be a consequence of a tidal encounter between the elliptical galaxy NGC 759 and a large spiral galaxy which was accompanied by a substantial gas accretion. ...

... ABSTRACT We report on the first results obtained from a new optical identification program of 123 faint Xґray sources with S(0.5--2 keV) ? 2 2 10 014 erg s 01 cm 02 serendipitously detected in ROSAT PSPC pointed observations. ... This evolution, coupled with the steep slope determined for the faint end of the Xґray luminosity function (8(LX ) / L 01:9 X ), implies that such objects could comprise 15--35 per cent of the soft (1ґ2 keV) Xґray background. ... 2 2 10 014 erg s 01 cm 02 . ...