Date: Mon, 17 Jun 2002 15:42:48 -0400 (EDT) From: Jon Miller <jmm@space.mit.edu> Subject: Bright Outburst of the Black Hole Candidate 4U 1543-47 X-ray outburst in 4U1543-47 J. M. Miller and R. A. Remillard (M.I.T.), for the RXTE ASM Team at M.I.T. and NASA Goddard Space Flight Center, report the detection of a new X-ray outburst in the black hole binary, 4U1543-47 (archival optical position: R.A. = 15h47m08.6s, Decl. = -47 40' 09", equinox J2000.0; +/- 1 "). The first detections with the RXTE ASM indicated a flux (2-12 keV) of 0.054 (+/- 0.009) Crab on June 16.683, rapidly increasing to 0.5 Crab (June 17.122) and 1.65 Crab (June 17.552). The X-ray spectrum is very soft, implying that the dominant component is thermal emission from the accretion disk. Optical and radio measurements are strongly encouraged.