Abdalla, H.Arcaro, C.Backes, M.Barnard, M.Böttcher, M.Chand, T.Chandra, S.Ndiyavala, H.Schutte, H.Seyffert, A.S.Van der Walt, D.J.Van Rensburg, C.Venter, C.Wadiasingh, Z.Zacharias, M.H.E.S.S. Collaboration2019-07-262019-07-262019Abdalla, H. et al. 2019. H.E.S.S. observations of the flaring gravitationally lensed galaxy PKS 1830-211. Monthly notices of the Royal Astronomical Society, 486(3):3886-3891. [https://doi.org/10.1093/mnras/stz1031]0035-87111365-2966 (Online)http://hdl.handle.net/10394/33060https://academic.oup.com/mnras/article/486/3/3886/5475660https://doi.org/10.1093/mnras/stz1031PKS 1830–211 is a known macrolensed quasar located at a redshift of z = 2.5. Its high-energy gamma-ray emission has been detected with the Fermi-Large Area Telescope (LAT) instrument and evidence for lensing was obtained by several authors from its high-energy data. Observations of PKS 1830–211 were taken with the High Energy Stereoscopic System (H.E.S.S.) array of Imaging Atmospheric Cherenkov Telescopes in 2014 August, 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 d from the alert flare, as expected from observations at other wavelengths. More than 12 h of good-quality data were taken with an analysis threshold of ∼67 GeV. The significance of a potential signal is computed as a function of the date and the average significance over the whole period. Data are compared to simultaneous observations by Fermi-LAT. No photon excess or significant signal is detected. An upper limit on PKS 1830–211 flux above 67 GeV is computed and compared to the extrapolation of the Fermi-LAT flare spectrumenGravitational lensing: strongDiffuse radiationGamma-rays: galaxiesArticle