Speaker
Dr
Julian Sitarek
(University of Lodz)
Description
PKS 1510-089 is one of only a handful of flat spectrum radio quasars
detected in very high energy (VHE, E > 100 GeV) gamma rays. Since the
first detection in 2009, despite showing strong variability in the
optical and GeV range, no VHE gamma-ray variability could be claimed
until a moderate 5-fold increase of the VHE gamma-ray flux was
observed in 2015. In May 2016, a major VHE gamma-ray flare was
observed from PKS 1510-089 by the H.E.S.S. and MAGIC
telescopes. Within ~5h of observations the VHE gamma-ray flux changed
by an order of magnitude showing short-term variability features for
the first time. Despite a soft intrinsic spectrum and strong
absorption in the extragalactic background light, the high flux of the
source allowed us to measure the gamma-ray spectrum up to the energy
of 0.7 TeV. We will report on the results of those observations as
well as of the supporting observations performed in the optical and
GeV range. We will also discuss possible explanations for the observed
emission.
Primary author
Dr
Julian Sitarek
(University of Lodz)
Co-authors
David Sanchez
(LAPP)
Dijana Dominis Prester
(University of Rijeka)
Elina Lindfors
(University of TUrku)
Mr
Felix Jankowsky
(Landessternwarte Heidelberg)
Mahmoud Mohamed
(University of Heidelberg)
Michael Zacharias
(North-West University: Potchefstroom, South Africa)
Tomislav Terzić
(University of Rijeka)
