C. B. Markwardt, National Research Council and Goddard Space Flight Center (GSFC); and J. H. Swank and F. E. Marshall, GSFC, report the detection of two new x-ray transients: "XTE J1819-254, whose position is consistent with that of the independently discovered SAX J1819.3-2525 (cf. IAUC 7119), had fluxes of 20, 37, 3, and 24 mCrab in the band 2-10 keV on Feb. 18.78, 22.65, 25.84, and Mar. 1.44 UT, respectively, and < 1 mCrab before that time. XTE J1743-363 has been active since the beginning of Feb. with intensities ranging from 3 to 15 mCrab. Variability of as much as 25 percent (r.m.s.) on approximately 1-min timescales has been seen. The best-fit position is R.A. = 17h42m58s, Decl. = -36o19' (equinox 2000.0), with an estimated uncertainty of 10'. Recent transients XTE J1710-281 (IAUC 6998) and XTE J1723-376 (IAUC 7103) remain active, with XTE J1710-281 showing evidence of an occultation (duration < 800 s). Semiweekly RXTE monitoring observations of the Galactic-center region will continue."
International Astronomical Union Circular
- Pub Date:
- March 1999