%0 Journal Article
%T Deep Broadband Observations of the Distant Gamma-ray Blazar PKS 1424+240
%+ Laboratoire Univers et Particules de Montpellier (LUPM)
%+ Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112))
%A Archambault, S.
%A Aune, T.
%A Behera, B.
%A Beilicke, M.
%A Benbow, W.
%A Berger, K.
%A Bird, R.
%A Biteau, J.
%A Bugaev, V.
%A Byrum, K.
%A Cardenzana, J.V
%A Cerruti, M.
%A Chen, X.
%A Ciupik, L.
%A Connolly, M.P.
%A Cui, W.
%A Dumm, J.
%A Errando, M.
%A Falcone, A.
%A Federici, S.
%A Feng, Q.
%A Finley, J.P.
%A Fleischhack, H.
%A Fortson, L.
%A Furniss, A.
%A Galante, N.
%A Gillanders, G. H.
%A Griffin, S.
%A Griffiths, S.T.
%A Grube, J.
%A Gyuk, G.
%A Hanna, D.
%A Holder, J.
%A Hughes, G.
%A Humensky, T.B.
%A Johnson, C.A.
%A Kaaret, P.
%A Kertzman, M.
%A Khassen, Y.
%A Kieda, D.
%A Krawczynski, H.
%A Krennrich, F.
%A Kumar, S.
%A Lang, M.J.
%A Madhavan, A.S
%A Maier, G.
%A Mccann, A.
%A Meagher, K.
%A Moriarty, P.
%A Mukherjee, R.
%A Nieto, D.
%A O'Faoláin de Bhróithe, A.
%A Ong, R.A.
%A Otte, A.N.
%A Park, N.
%A Pohl, M.
%A Popkow, A.
%A Prokoph, H.
%A Quinn, J.
%A Ragan, K.
%A Rajotte, J.
%A Reyes, L.C.
%A Reynolds, P.T.
%A Richards, G.T.
%A Roache, E.
%A Sembroski, G. H.
%A Shahinyan, K.
%A Staszak, D.
%A Telezhinsky, I.
%A Tucci, J.V.
%A Tyler, J.
%A Varlotta, A.
%A Vassiliev, V. V.
%A Vincent, S.
%A Wakely, S.P.
%A Weinstein, A.
%A Welsing, R.
%A Wilhelm, A.
%A Williams, D.A.
%A Ackermann, M.
%A Ajello, M.
%A Albert, A.
%A Baldini, L.
%A Bastieri, D.
%A Bellazzini, R.
%A Bissaldi, E.
%A Bregeon, J.
%A Buehler, R.
%A Buson, S.
%A Caliandro, G.A.
%A Cameron, R.A.
%A Caraveo, P.A.
%A Cavazzuti, E.
%A Charles, E.
%A Chiang, J.
%A Ciprini, S.
%A Claus, R.
%A Cutini, S.
%A d'Ammando, F.
%A de Angelis, A.
%A de Palma, F.
%A Dermer, C.D.
%A Digel, S.W.
%A Di Venere, L.
%A Drell, P.S.
%A Favuzzi, C.
%A Franckowiak, A.
%A Fusco, P.
%A Gargano, F.
%A Gasparrini, D.
%A Giglietto, N.
%A Giordano, F.
%A Giroletti, M.
%A Grenier, I.A.
%A Guiriec, S.
%A Jogler, T.
%A Kuss, M.
%A Larsson, S.
%A Latronico, L.
%A Longo, F.
%A Loparco, F.
%A Lubrano, P.
%A Madejski, G.M.
%A Mayer, M.
%A Mazziotta, M.N.
%A Michelson, P.F.
%A Mizuno, T.
%A Monzani, M.E.
%A Morselli, A.
%A Murgia, S.
%A Nuss, E.
%A Ohsugi, T.
%A Ormes, J.F.
%A Paneque, D.
%A Perkins, J.S.
%A Piron, F.
%A Pivato, G.
%A Rainò, S.
%A Razzano, M.
%A Reimer, A.
%A Reimer, O.
%A Ritz, S.
%A Schaal, M.
%A Sgrò, C.
%A Siskind, E.J.
%A Spinelli, P.
%A Takahashi, H.
%A Tibaldo, L.
%A Tinivella, M.
%A Troja, E.
%A Vianello, G.
%A Werner, M.
%A Wood, M.
%< avec comité de lecture
%J Astrophys.J.Lett.
%V 785
%P L16
%8 2014
%D 2014
%Z 1403.4308
%R 10.1088/2041-8205/785/1/L16
%K BL Lacertae objects: individual (PKS 1424+240)-cosmic background radiation
%K gamma rays: galaxies
%K photon: flux
%K photon: absorption
%K gamma ray: flux
%K detector: optical
%K X-ray: detector
%K cosmic radiation: interaction
%K spectral
%K blazar
%K VHE
%K VERITAS
%K pair production
%K statistics
%K background
%K redshift
%K opacity
%Z Physics [physics]/Astrophysics [astro-ph]Journal articles
%X We present deep VERITAS observations of the blazar PKS 1424+240, along with contemporaneous Fermi Large Area Telescope, Swift X-ray Telescope, and Swift UV Optical Telescope data between 2009 February 19 and 2013 June 8. This blazar resides at a redshift of z ≥ 0.6035, displaying a significantly attenuated gamma-ray flux above 100 GeV due to photon absorption via pair-production with the extragalactic background light. We present more than 100 hr of VERITAS observations over three years, a multiwavelength light curve, and the contemporaneous spectral energy distributions. The source shows a higher flux of (2.1 ± 0.3) × 10–7 photons m–2 s–1 above 120 GeV in 2009 and 2011 as compared to the flux measured in 2013, corresponding to (1.02 ± 0.08) × 10–7 photons m–2 s–1 above 120 GeV. The measured differential very high energy (VHE; E ≥ 100 GeV) spectral indices are Γ = 3.8 ± 0.3, 4.3 ± 0.6 and 4.5 ± 0.2 in 2009, 2011, and 2013, respectively. No significant spectral change across the observation epochs is detected. We find no evidence for variability at gamma-ray opacities of greater than τ = 2, where it is postulated that any variability would be small and occur on timescales longer than a year if hadronic cosmic-ray interactions with extragalactic photon fields provide a secondary VHE photon flux. The data cannot rule out such variability due to low statistics.
%G English
%Z VERITAS
%Z Fermi-LAT
%L hal-02024305
%U https://hal.science/hal-02024305
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%~ INSU
%~ UNIV-PARIS7
%~ CNRS
%~ UNIV-MONTP2
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