Spectral modeling of black hole x-ray binary 4U 1543-47 during 2021 outburst using NuSTAR data

We present a spectral analysis of NuSTAR observations of the black hole X-ray binary(BHXB) 4U 1543-47 at 10 epochs during the 2021 outburst. The black hole x-ray binary 4U 1543-47 was discovered during an outburst in 1971 august 17. It exhibited three additional outbursts almost every 10 years in 1983, 1992 and 2002. A new outburst started on 2021 June 11, after the 19 years of the last outburst. MAXI reported this source as the brightest source detected in 11 years and NICER reported it as the brightest black hole target observed till now. NuSTAR observes the sky in hard x-ray (3–79 keV) that consists of comptonization and reflection components in the spectrum of BHXBs. The source was observed in soft state and its spectra fitted with disk blackbody and power law. We find an absorption feature in the spectra around 7-7.5 KeV as discussed in the poster. The work on the model that explains the absorption feature is still under process. Apart from the absorption feature, we are working on the evolution of disk-corona geometry during the outburst.