The evolution of Rapid Burster outbursts

We describe the evolutionary progression of an outburst of the Rapid Burste r. Four outbursts have been observed with the Rossi X-Ray Timing Explorer b etween 1996 February and 1998 May, and our observations are consistent with a standard evolution over the course of each. An outburst can be divided i nto two distinct phases. Phase I is dominated by type I bursts, with a stro ng persistent emission component; it lasts for 15-20 d. Phase II is charact erized by type II bursts, which occur in a variety of patterns. The light c urves of time-averaged luminosity for the outbursts show some evidence for reflares, similar to those seen in soft X-ray transients. The average recur rence time for Rapid Burster outbursts during this period was 218 d, in con trast to an average similar to 180-d recurrence period observed during 1976 -1983.