X-ray Studies of Blazar 1ES 1959+650 Using SWIFT & XMM-NEWTON Satellite

TL;DR

This study analyzes the X-ray variability and spectral properties of blazar 1ES 1959+650 using Swift and XMM-Newton data, revealing insights into its emission mechanisms, magnetic field, and particle acceleration processes.

Contribution

It provides a comprehensive analysis of flux and spectral variability over multiple timescales, constrains the magnetic field, and explores particle acceleration through spectral correlations.

Findings

Detected soft and hard X-ray lags indicating complex emission processes.

Constrained the magnetic field of the emission region to 0.64 Gauss.

Found correlations between spectral parameters suggesting stochastic acceleration.

Abstract

High synchrotron energy peaked blazar 1ES 1959+650 is studied with Swift and XMM-Newton satellite in total 127 observations during the period June 2018-December 2020. We extensively studied its flux and spectral variability on intra-day and long-term timescales. Discrete correlation function analysis between soft and hard X-ray bands indicates soft as well as hard lags. The results are used to constrain the magnetic field of the emitting region which is found to be 0.64 (0.05) Gauss. On long-term timescales, distribution of fluxes shows lognormality behaviour which could be attributed to minijets-in-a-jet model or might be due to the propagation of relativistic shocks down the jet. The spectral energy distribution around the synchrotron peak is well described by the log parabola model. Spectral parameters like peak energy E$_{p}$, curvature $\beta$ and the peak luminosity L$_{p}$ are derived from spectral analysis. Their correlations are studied to constrain the acceleration processes of the emitting particles. E$_{p}$ shows strong correlation with L$_{p}$ during the high state of the source which indicates spectral changes might be caused by the variations of the average electron energy. Low values of curvature parameter $\beta$ and a weak correlation between E$_{p}$ and ${\beta}$ indicates co-existence of stochastic/statistical acceleration of electrons in the emitting region. Implications of other results are also discussed.