XTE J1650-500 : Hard X-ray Nova

The RXTE/ASM detected X-ray emission from a new source, XTE J1650-500. The first detection was made on September 5.637, with an X-ray intensity (2-12 keV) of 0.14(.02) Crab, rising to 0.24(.01) Crab on Sept. 6.432 and 0.27(.01) Crab on Sept. 6.896 (vsnet-campaign 1158). The continuum spectrum was a power law with a photon index of 1.5 and a small amount of a black body with kT = 1.2 keV, typical of hard states of black hole candidates (vsnet-campaign 1160). Its optical counterpart was detected at B=17 and I=17.2+/-0.2 as reported by Castro-Tirado et al. and Groot et al. (vsnet-campaign-xray 89, vsnet-campaign-xray 90). IAUC No. 7710 tells that Augusteijn et al. obtained an optical spectrum which shows Balmer emission lines, and they reported that the identification of the optical counterpart has been confirmed (vsnet-campaign-xray 92). M. Revnivtsev reported the detection of QPOs of 1.13-2.73 Hz with amplitudes of 5-7% through RXTE X-ray observations. X-ray spectrum is similar to that of Cyg X-1 and other black hole binaries in the low/hard spectral state (vsnet-campaign-xray 93).

Other related articles: vsnet-campaign-xray 87, 88, 91,

Optical images: http://cfa-www.harvard.edu/~pgroot/XTEJ1650-50DDS.ps, http://cfa-www.harvard.edu/~pgroot/XTEJ1650-50OGLE.ps