Close stars and an inactive accretion disc in Sgr A*: eclipses and flares

A cold neutral and extremely dim accretion disc may be present as a remnant of past vigorous activity around the black hole at our Galactic Centre (GC). Here we discuss ways to detect such a disc through its interaction with numerous stars present in the central 0.01 pc of the Galaxy. The first major effect expected is X-ray and near-infrared (NIR) flares arising when stars pass through the disc. The second is eclipses of the stars by the disc. We point out conditions under which the properties of the expected X-ray flares are similar to those discovered by Baganoff et al. The combination of the expected flares and eclipses offers an invaluable tool for constraining the disc density, size, plane and even direction of rotation. The winds of the O-type stars are optically thick to free–free absorption in radio frequencies. If present near the Sgr A* core, these stellar winds can modulate and even occult the radio source.