TITLE: GCN CIRCULAR NUMBER: 393 SUBJECT: GRB990806: possible X-ray afterglow, BeppoSAX DATE: 99/08/07 16:31:22 GMT FROM: Luigi Piro at IAS/CNR Frascati Giangiacomo Gandolfi, on behalf of BeppoSAX Mission Scientist, reports: A BeppoSAX follow-up of GRB990806 started about 8 hr after the burst. A quick look analysis of the first orbits of the MECS data at SOC shows an object, previously unknown, inside the refined error circle of the WFC. Preliminary coordinates are: R.A.(2000)= 47.674 DEC(2000)= -68.113 The error radius is 2' BeppoSAX will continue its observation and monitoring of this source until August 8.