We report on the detection of very high energy (VHE; E > 100 GeV) γ-ray emission from the BL Lac objects KUV 00311−1938 and PKS 1440−389 with the High Energy Stereoscopic System (H.E.S.S.). H.E.S.S. observations were accompanied or preceded by multiwavelength observations with Fermi/LAT, XRT and UVOT onboard the Swift satellite, and ATOM. Based on an extrapolation of the Fermi/LAT spectrum towards the VHE γ-ray regime, we deduce a 95 per cent confidence level upper limit on the unknown redshift of KUV 00311−1938 of < 0.98 and of PKS 1440−389 of < 0.53. When combined with previous spectroscopy results, the redshift of KUV 00311−1938 is constrained to 0.51 ≤ < 0.98 and of PKS 1440−389 to 0.14 ⪅ < 0.53.
Very high energy γ-ray emission from two blazars of unknown redshift and upper limits on their distance
- H. Abdalla et al. (H.E.S.S. Collaboration)
- Monthly Notices of the Royal Astronomical Society 494, 5590–5602 (2020)
- 2020
Abstract
Auxiliary informations
Figure 2, left panel: KUV 00311-1938 H.E.S.S. observed spectra: [DAT]
The <E> column is the mean energy of the bin, and the dFlux column is the flux point, with the other colmuns being the respective uncertainties
Figure 2, right panel: PKS 1440-389 H.E.S.S. observed spectra: [DAT]
The <E> column is the mean energy of the bin, and the dFlux column is the flux point, with the other colmuns being the respective uncertainties
Figure 3, upper panel: KUV 00311-1938 MWL SED points: [CSV]
Because the H.E.S.S spectrum is integrated over a very long time period, each point comes with a MJD start and stop date.
Figure 3, lower panel: PKS 1440-389 MWL SED points: [CSV]
Since the H.E.S.S observations happened over a very short time period, there are no start and stop dates.
