Peculiar X-ray flares in HBLs, a case study of 1ES 1959+650, Mrk421 and PKS 2155-304

The high energy peaked BL Lac objects (HBLs) are a subclass of blazars having its synchrotron component of spectral energy distribution (SEDs) peaking in soft X-rays. The peak position of the synchrotron component and spectral shapes have been seen changing during various flaring states. The harder when brighter is the most common trend seen during flares in HBLs. The spectral changes along with peak position can be used to decipher the physical mechanisms and particle accelerations owing to the fact that X-ray spectra of these objects are nothing but clean synchrotron emission. AstroSat has been following a number of HBLs since its launch in 2015. In our present work, we have analyzed multi-wavelength data focusing on the three well-known HBLs namely, 1ES 1959+650, PKS 2155-304, and Mrk421, for the duration of wideband X-ray spectra from AstroSat and have modeled flux v/s spectral slopes. These results are found to be consistent with the parameters from broadband SED modeling. I intend to discuss our exciting work during the event.