  The light curves of GRS 1915+105 observed with RXTE on October 15, 1996
reveal a wide range of transient activity including regular bursts with a
recurrence time of about 1 minute, irregular bursts, and dips. In contrast to
bursts from other sources, a secondary (and a tertiary) weaker burst
immediately following the primary burst are observed. Detailed energy spectra
indicate that the source softens during the main outburst and successively
hardens during the secondary and tertiary bursts. This may imply that the
accretion flow has a corona-disk configuration and that the relative
contribution of the hot corona decreases during the primary bursts and
increases during the secondary and tertiary bursts. The primary burst profile
resembles the bursts produced in the time dependent evolutions of accretion
disks which are thermally and viscously unstable. The secondary burst may
reflect an inward shift of the inner edge of the disk which results in a
greater release of gravitational binding energy.
