A limit on nuclear activity in Leo A

ROSAT HRI observations of Leo A are analysed in order to complement a recent X-ray survey of the centres of Local Group galaxies (Zang & Meurs 2001). It is likely that high-energy cores in galaxies are indicative of some level of nuclear activity. The upper limit 0.12.4 keV luminosity determined for Leo A (log LX < 35.77) is consistent with the results that were obtained for other small Local Group systems. Leo A represents the lowest optical luminosity Irregular galaxy in the Local Group that has been studied at X-rays. Also the ROSAT All Sky Survey data allow to derive a (less constraining) upper limit flux for this galaxy.