Observation of X-ray transient XTE J1748-288 by the Indian X-ray AstronomyExperiment

The observations of a newly discovered X-ray transient source XTE J1748-288 were made in the energy band 2 - 18 keV with the Indian X-ray Astronomy Ex periment(IXAE) on the IRS-P3 satellite during 1998, June 14-25. The source count rate declined gradually with an exponential decay time of 19 +/- 1.6 days. The X-ray light curves showed no significant intensity variations on short time scales (less than or equal to 10s). The power density spectrum o btained from timing analysis of the data shows no quasi-periodic oscillatio ns in the frequency range of 0.002 Hz to 5 Hz. From the observed X-ray and radio characteristics, it is suggested that the X-ray source in XTE J1748-2 88 is more likely to be a black hole rather than a neutron star.