Abstract Details

Name: Jyotishree Hota
Affiliation: Department of Physics and Astronomy, NIT Rourkela
Conference ID: ASI2021_312
Title : Understanding the X-ray spectral curvature ofMKN 421 using broadband AstroSat observations
Authors and Co-Authors : Jyotishree Hota(NIT Rourkela), Ranjeev Misra (IUCAA Pune), Zahir Shah(IUCAA pune), Ananta Charan Pradhan (NIT Rourkela)
Abstract Type : Poster
Abstract Category : Stars, ISM and Galaxy
Abstract : We present a detailed X-ray spectral study of the high energy peaked blazar MKN421 using the simultaneous broadband observations from the LAXPC and SXT instruments on-board AstroSat. The data was obtained as ToO observation during the period 3rd January 2017 – 8th January 2017. The X-ray spectrum of Mkn 421 showing significant spectral curvature is usually described by log-parabola model, however, the model fails to give the information of underlying physical parameters as the exact relationship of model parameters with the underlying physical quantities is not clear. Therefore in order to obtain the information of underlying physical parameters, we reproduce the X-ray spectrum with the analytical models viz. energy-dependent electron diffusion model(EDED) and the power law with γ-max model. Our study showed that both the models fit the X-ray spectrum reasonably good, EDED model provides a better reduced-χ2 values. Moreover, we studied the correlation between EDED model parameters (norm, ξ0 and κ) and the observed quantities using the Spearmanrank correlation method. A significant anti-correlation is observed between κ and ξ0 with rs= -0.95 (prs= 2.99×10(−17)) and similar anti correlation is also obtained for the case of ξ0 and F(0.5−18.0) with rs= -0.89 (prs= 3.21×10^(−12)). The strong anti correlation between model parameters and observed quantities allows us to constrain the underlying physical parameters viz. source magnetic field (B) and jet Dopper factor (δ)