July 29, 2015 to August 6, 2015
World Forum
Europe/Amsterdam timezone

Spectral characteristics of Mrk$\,$501 during the 2012 and 2014 flaring states

Jul 30, 2015, 11:15 AM
Yangtze 1 (World Forum)

Yangtze 1

World Forum

Churchillplein 10 2517 JW Den Haag The Netherlands
Oral contribution GA-EX Parallel GA01 EGAL


Mr Gabriele Cologna (LSW Heidelberg)


The BL$\,$Lac object Mrk$\,$501 was observed at Very High Energies (E$\,$>$\,$100$\,$GeV) with H.E.S.S. (High Energy Stereoscopic System) between 2004 and 2014. The source is detected with high significance above $\sim$2$\,$TeV in $\sim$13.6$\,$h livetime. The observations include periods of low flux and active phases. This led to the detection of strong flaring events, which in 2014 showed a flux level comparable to the 1997 historical maximum. Such high flux states enabled spectral variability and flux variability studies down to a timescale of a few minutes in the 2-20$\,$TeV energy range. During the 2014 flare, the source is clearly detected in each time bin. The spectrum does not show intrinsic curvature in this energy range. Flux dependent spectral analyses are also carried out. The peculiarity of this study resides in the unprecedented combination of short timescales and an energy coverage that extends significantly above 10$\,$TeV. The high energies allow us to probe the effect of EBL absorption at low redshifts, jet physics and LIV. The multiwavelength context of these VHE observations will be presented as well.
Registration number following "ICRC2015-I/" 488
Collaboration H.E.S.S.

Primary author

Mr Gabriele Cologna (LSW Heidelberg)


Prof. Agnieszka Jacholkowska (LPNHE Paris) Dr Alicja Wierzcholska (LSW Heidelberg) Dr Andrew Taylor (DIAS Dublin) Mr Carlo Romoli (DIAS Dublin) Prof. Frank Rieger (MPIK Heidelberg) Mr Mahmoud Mohamed (LSW Heidelberg) Dr Nachiketa Chakraborty (MPIK Heidelberg) Prof. Stefan Wagner (LSW Heidelberg)

Presentation materials