Very high energy γ-ray emission from two blazars of unknown redshift and upper limits on their distance. Issue 4 (23rd April 2020)

• Record Type: Journal Article
• Authors: Abdalla, H; Adam, R; Aharonian, F; Ait Benkhali, F; Angüner, E O; Arakawa, M; Arcaro, C; Armand, C; Armstrong, T; Ashkar, H; Backes, M; Baghmanyan, V; Barbosa Martins, V; Barnacka, A; Barnard, M; Becherini, Y; Berge, D; Bernlöhr, K; Böttcher, M; Boisson, C; Bolmont, J; Bonnefoy, S; Bregeon, J; Breuhaus, M; Brun, F; Brun, P; Bryan, M; Büchele, M; Bulik, T; Bylund, T; Caroff, S; Carosi, A; Casanova, S; Chand, T; Chandra, S; Chen, A; Cotter, G; Curyło, M; Davids, I D; Davies, J; Deil, C; Devin, J; deWilt, P; Dirson, L; Djannati-Ataï, A; Dmytriiev, A; Donath, A; Doroshenko, V; Dyks, J; Egberts, K; Eichhorn, F; Emery, G; Ernenwein, J -P; Feijen, K; Fegan, S; Fiasson, A; Fontaine, G; Funk, S; Füßling, M; Gabici, S; Gallant, Y A; Giavitto, G; Giunti, L; Glawion, D; Glicenstein, J F; Gottschall, D; Grondin, M -H; Hahn, J; Haupt, M; Hermann, G; Hinton, J A; Hofmann, W; Hoischen, C; Holch, T L; Holler, M; Hörbe, M; Horns, D; Huber, D; Iwasaki, H; Jamrozy, M; Jankowsky, D; Jankowsky, F; Jardin-Blicq, A; Joshi, V; Jung-Richardt, I; Kastendieck, M A; Katarzyński, K; Katsuragawa, M; Katz, U; Khangulyan, D; Khélifi, B; Klepser, S; Kluźniak, W; Komin, Nu; Konno, R; Kosack, K; Kostunin, D; Kreter, M; Lamanna, G; Lemière, A; Lemoine-Goumard, M; Lenain, J -P; Leser, E; Levy, C; Lohse, T; Lypova, I; Mackey, J; Majumdar, J; Malyshev, D; Malyshev, D; Marandon, V; Marchegiani, P; Marcowith, A; Mares, A; Martí-Devesa, G; Marx, R; Maurin, G; Meintjes, P J; Moderski, R; Mohamed, M; Mohrmann, L; Moore, C; Morris, P; Moulin, E; Muller, J; Murach, T; Nakashima, S; Nakashima, K; de Naurois, M; Ndiyavala, H; Niederwanger, F; Niemiec, J; Oakes, L; O'Brien, P; Odaka, H; Ohm, S; de Oña Wilhelmi, E; Ostrowski, M; Panter, M; Parsons, R D; Peyaud, B; Piel, Q; Pita, S; Poireau, V; Noel, A P; Prokhorov, D A; Prokoph, H; Pühlhofer, G; Punch, M; Quirrenbach, A; Raab, S; Rauth, R; Reimer, A; Reimer, O; Remy, Q; Renaud, M; Rieger, F; Rinchiuso, L; Romoli, C; Rowell, G; Rudak, B; Ruiz-Velasco, E; Sahakian, V; Sailer, S; Saito, S; Sanchez, D A; Santangelo, A; Sasaki, M; Scalici, M; Schüssler, F; Schutte, H M; Schwanke, U; Schwemmer, S; Seglar-Arroyo, M; Senniappan, M; Seyffert, A S; Shafi, N; Shiningayamwe, K; Simoni, R; Sinha, A; Sol, H; Specovius, A; Spencer, S; Spir-Jacob, M; Stawarz, Ł; Steenkamp, R; Stegmann, C; Steppa, C; Takahashi, T; Tavernier, T; Taylor, A M; Terrier, R; Tiziani, D; Tluczykont, M; Tomankova, L; Trichard, C; Tsirou, M; Tsuji, N; Tuffs, R; Uchiyama, Y; van der Walt, D J; van Eldik, C; van Rensburg, C; van Soelen, B; Vasileiadis, G; Veh, J; Venter, C; Vincent, P; Vink, J; Völk, H J; Vuillaume, T; Wadiasingh, Z; Wagner, S J; Watson, J; Werner, F; White, R; Wierzcholska, A; Yang, R; Yoneda, H; Zacharias, M; Zanin, R; Zargaryan, D; Zdziarski, A A; Zech, A; Zhu, S J; Zorn, J; Żywucka, N; Cerruti, M;
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 494:Issue 4(2020)
• Page Start: 5590
• Page End: 5602
• Publication Date: 2020-04-23
• Subjects: BL Lacertae objects: individual -- galaxies: high-redshift -- gamma-rays: general -- Resolved and unresolved sources as a function of wavelength; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/staa999
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: 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 $z$ < 0.98 and of PKS 1440−389 of $z$ < 0.53. When combined with previous spectroscopy results, the redshift of KUV 00311−1938 is constrained to 0.51 ≤ $z$ < 0.98 and of PKS 1440−389 to 0.14 ⪅ $z$ < 0.53.