Speaker
Description
Blazars are highly variable sources and show variability down to minute time scales. The current generation of Imaging Atmospheric Cherenkov Telescopes like MAGIC are able to probe the spectra of the brightest blazars down to daily and hourly time scales, especially in their flaring states. In this work, we characterize the variability and daily Spectral Energy Distribution (SED) evolution of the archetypal TeV blazar Mrk421 using simultaneous MAGIC very high energy (VHE band, >100 GeV) and multi-wavelength (MWL) observations from radio all the way up to gamma ray bands during the Nov 2009 to June 2010 campaign.
Mrk421 displayed its strongest flare ever observed in February 2010 when VERITAS measured VHE flux of ~15 Crab units above 200 GeV. VLBA data unveils contemporaneous ejections of radio features for the first time for Mrk421. The variability and MWL cross-correlations were analyzed along with the temporal evolution of the daily SEDs to gain insights into the emission processes of this flare that exhibits unprecedented characteristics for the source. The strong daily flux variations and complex intra-band correlation patterns challenge the single zone Synchrotron Self Compton model typically applied for the source.
