Detection of thermonuclear X-ray bursts and dips from the X-ray binary 4U 1323-62 with AstroSat/LAXPC

Abstract

Using data from the Large Area X-ray Proportional Counter (LAXPC) on the AstroSat satellite, we observed Type-1 thermonuclear X-ray bursts from the low mass X-ray binary neutron star 4U 1323–62. Observations of 4U 1323-62 that were carried out during the performance verification phase of the AstroSat satellite indicated six thermonuclear X-ray bursts in a total effective exposure of ∼49.5 ks for about two consecutive days. Recurrence time of the detected thermonuclear bursts is in accordance with the orbital period of the source, ∼9400 s. Moreover, the light curve of 4U 1323–62 revealed the presence of two dips. We present the results from time-resolved spectroscopy performed during all of the six X-ray bursts and also report the detection of a known low frequency quasi-periodic oscillation (LFQPO) at ∼1 Hz from the source. However, any evidence of kilohertz QPO was not found. We have shown the burst profile at different energy ranges. Assuming a distance of 10 kpc, we observed a mean flux of ∼1.8×10−9 erg cm2 s−1. The radius of the blackbody is found to be highly consistent with the blackbody temperature and the blackbody flux of the bursts.