Chandra--ASCA--RXTE observations of the micro-quasar GRS 1915+105
  A Chandra AO1 30ks HETGS observation of the X-ray transient micro-quasar GRS 1915+105 reveals absorption edges and faint line emission over the HETG energy range. We find from a preliminary analysis evidence for prominent neutral K edges associated with iron, silicon, magnesium, and tentatively sulphur. The column densities assuming solar abundances are consistent with ~ few x $10^{22} cm^{-2}$ in excess of the Galactic value, and may point to surrounding cold material associated with GRS 1915+105. Neutral Fe K$\alpha$ emission, and ionized absorption from Fe XXV and Fe XXVI are resolved. We limit our discussion to the Chandra results. 
J.C. Lee (MIT), N.S. Schulz (MIT), C.S. Reynolds (JILA), A.C. Fabian   (IoA-Cambridge), E.G. Blackman (U. Rochester)