Contribution Poster (A0 portrait)
H.E.S.S. observations of the flaring gravitationally lensed galaxy PKS 1830-211
PKS 1830-211 is a known macrolensed AGN located at a redshift of z=2.5. Its high energy gamma ray emission has been detected with the Fermi-LAT instrument and evidence for lensing was obtained by several authors from its high energy data.?Aims. Observations of PKS 1830-211 were taken with the H.E.S.S. array of Imaging Atmospheric Cherenkov Telescopes in August 2014, following a flare alert by the Fermi- LAT collaboration. The H.E.S.S observations were aimed at detecting a gamma ray flare delayed by 20-27 days from the alert flare, as expected from observations at other wavelengths. An upper limit on PKS 1830-211 flux above 100 GeV is computed and compared to the extrapolation of the Fermi-LAT flare spectrum. Potential constraint on EBL for future observations of this source are studied.