| Abstract : | One of the most active transient black hole binary systems is 4U 1630-47. Exhibiting outbursts
every few hundred days and every individual outburst lasting around a hundred days. Here we
look at the spectral and timing features of minor flares of 1996, 1998, 1999-2000, 2000-2001, and 2005-2006. One clear distinction between these minor outburst and the major outburst of 2002-2004 [Choudhury et al., 2015] is the strong appearance of QPOs in the major outburst. The minor outburst show very few to no QPOs, however, the 1998 outburst showed an overwhelming number of QPOs compared to other minor outbursts. This suggests some difference in the physical interactions and geometrical setup of the accretion process of 1998 outburst as compared to the other minor outbursts.Apart from that two distinct population of QPOs are observed single and twin QPOs.
The data from NASA’s Rossi X-ray timing explorer has been used. The proportional counter array (PCA) has monitored the source extensively in its narrow field of view. RXTE’s entire life so to maintain uniformity only PCU 2 data was used for all the observations. The data analysis and reduction were carried out using HEASOFT which consists of FTOOLS, XRONOS, XSPEC, etc. The power density spectrum (PDS) was obtained from event mode data for the complete energy band using POWSPEC.
The spectral fitting of PCA data for all observations were fitted with a single model consisting
of three components, a multicolored disc blackbody (diskbb) which is prominent at lower energies, a power law component dominating at higher energies and a isotropic reflection component (reflect) [Makishima et al., 1986] of the power law emission arising from the photons of accretion disc reflected from the electron cloud. There is one more component that compensates for the interstellar absorption (tbabs).
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