First Results on Long-Term Multiwavelength Variability Analysis in Mrk 421

¹ Universidad Complutense de Madrid, Madrid, Spain
² European Space Astronomy Center (ESAC-ESA), Madrid, Spain

^a e-mail: eracero@sciops.esa.int
^b e-mail: icalle@sciops.esa.int

Published online: 9 December 2013

Abstract

Due to the broad-band nature of the emission from blazars, strong efforts are being placed in recent years on simultaneous multiwavelength campaigns as a way to understand the mechanisms responsible for the acceleration of ultra-relativistic particles in these objects. The present work aims at providing a systematic study of the broadband long-term variability properties of the TeV blazar, Mrk 421, by gathering archival multiwavelength data spanning nearly two decades in time over several energy bands, from radio frequencies through x-rays to high and very high γ-ray energies. The lightcurves at these energies have been characterized over long periods (≈months) using several statistical methods, in order to study variability over long-term timescales and the dependence of this variability with flux and energy, aiming ultimately at shedding some light onto the physical mechanisms that drive blazar emission. We present in this work the preliminary results of the variability analysis for Mrk 421, and it will be extended in the future to see if the properties found are particular of this source or if they can be extended to the blazar class.