BBXRT Observation of MX0836-42

The x-ray transient MX0836-42 was observed with a luminosity of 4 times 10(36) ergs * sec(-1) (using a distance of 10 kpc) by BBXRT for 25 minutes during its shuttle flight in December, 1990. The moderate-resolution energy spectrum is analysed in the context of a thermal bremsstrahlung model and a model developed by Taam and Meszaros which takes into account the irradiation of the accretion disk by the boundary layer in a low-mass binary system. No emission lines are observed and an upper limit on the iron line emission is derived. Comparisons are made with the contemporaneous GINGA observation and two earlier observations by UHURU and OSO-7.