The high-energy gamma-ray emission of AP Librae

The gamma-ray spectrum of the low-frequency-peaked BL Lac (LBL) object AP Librae is studied, following the discovery of very-high-energy (VHE; E > 100 GeV) gamma-ray emission up to the TeV range by the H.E.S.S. experiment. Thismakes AP Librae one of the few VHE emitters of the LBL type. The measured spectrum yields a flux of (8.8 +/- 1.5(stat) +/- 1.8(sys)) x 10(-12) cm(-2) s(-1) above 130 GeV and a spectral index of Gamma = 2.65 +/- 0.19(stat) +/- 0.20(sys). This study also makes use of Fermi-LAT observations in the high energy (HE, E > 100 MeV) range, providing the longest continuous light curve (5 years) ever published on this source. The source underwent a flaring event between MJD 56 306-56 376 in the HE range, with a flux increase of a factor of 3.5 in the 14 day bin light curve and no significant variation in spectral shape with respect to the low-flux state. While the H.E.S.S. and (low state) Fermi-LAT fluxes are in good agreement where they overlap, a spectral curvature between the steep VHE spectrum and the Fermi-LAT spectrum is observed. The maximum of the gamma-ray emission in the spectral energy distribution is located below the GeV energy range.

M. V. Fernandes | L. Oakes | T. Bulik | G. Anton | J. Tjus | J. Conrad | U. Katz | E. Moulin | T. Lohse | T. Mccomb | W. Domainko | C. Deil | V. Zabalza | S. Rosier-Lees | A. Quirrenbach | A. Lopatin | C. Venter | M. Raue | R. Parsons | S. Ohm | C. Stegmann | I. Davids | W. Hofmann | G. Fontaine | N. Maxted | R. Schlickeiser | Michael Backes | B. Degrange | F. Aharonian | D. Horns | Y. Gallant | S. Fegan | D. Horan | K. Kosack | Y. Becherini | F. Feinstein | C. Naumann | Andrew Taylor | A. Santangelo | L. Drury | G. Maurin | S. Wagner | S. Colafrancesco | C. Farnier | K. Valerius | B. Peyaud | H. Odaka | L. Stawarz | H. Dickinson | B. Opitz | M. Ward | A. Hillert | B. V. Soelen | J. Tavernet | M. Panter | A. Barnacka | E. Birsin | E. Bissaldi | J. Biteau | M. Boettcher | C. Boisson | J. Bolmont | P. Bordas | P. Brun | S. Casanova | M. Daniel | M. Naurois | A. Djannati-Ataï | G. Dubus | J. Dyks | M. Dyrda | K. Egberts | P. Eger | A. Fiasson | G. Giavitto | B. Giebels | J. Glicenstein | M. Grudzinska | J. Hahn | G. Henri | G. Hermann | P. Hofverberg | A. Jacholkowska | M. Jamrozy | M. Janiak | I. Jung | K. Katarzyński | B. Khélifi | W. Kluźniak | D. Kolitzus | N. Komin | G. Lamanna | J. Lenain | A. Marcowith | R. Moderski | J. Niemiec | S. Nolan | M. Ostrowski | I. Oya | M. P. Arribas | P. Petrucci | S. Pita | M. Punch | A. Reimer | O. Reimer | M. Renaud | F. Rieger | L. Rob | B. Rudak | C. Rulten | V. Sahakian | A. Schulz | U. Schwanke | S. Schwarzburg | S. Schwemmer | H. Sol | R. Steenkamp | F. Stinzing | R. Terrier | M. Tluczykont | C. Eldik | G. Vasileiadis | A. Viana | P. Vincent | Q. Weitzel | R. White | A. Wierzcholska | M. Zacharias | A. Zdziarski | A. Zech | H. Voelk | M. Lemoine-Goumard | Y. Cui | G. Puehlhofer | Rui-zhi Yang | G. Rowell | F. Brun | H. Laffon | V. Marandon | P. Fortin | S. Klepser | P. Chadwick | O. Hervet | I. Sushch | S. Kaufmann | T. Murach | F. Benkhali | P. deWilt | M. Grondin | J. Hinton | M. Holler | F. Jankowsky | M. Kastendieck | A. Lemière | R. Marx | P. Meintjes | M. Meyer | M. Mohamed | E. Wilhelmi | S. Raab | C. Romoli | T. Tavernier | C. Trichard | T. Vuillaume | M. Fuessling | R. Reyes | R. Wagner | A. Akhperjanian | J. Brucker | A. Cheesebrough | M. Dalton | P. Espigat | G. Heinzelmann | C. Jahn | D. Klochkov | T. Kneiske | J. Méhault | G. Pelletier | F. Volpe | I. Reichardt | M. Mayer | S. Carrigan | J. Harris | F. Schuessler | H. Poon | P. Willmann | A. Abramowski | H. Zechlin | A. Balzer | R. Chalme-Calvet | G. Cologna | C. Couturier | K. Dutson | T. Edwards | M. Gajdus | T. Garrigoux | M. Kieffer | S. Krakau | F. Krayzel | J. Lefaucheur | N. Pekeur | G. Spengler | F. Spies | K. Stycz | P. Wagner | D. Wouters | R. Chaves | S. Balenderan | D. Fernandez | U. Menzler | J. Pérez | M. Vorster | M. Weidinger | D. Sanchez | J. Finke | A. Foerster | Chia-Chun Lu | M. Chretien | E. Anguener | K. Bernlhr | S. Haeffner | P. Krueger | A. Wrnlein | A. Reimer | J. Conrad | A. Schulz | R. White | Camille Couturier | M. Arribas | A. Taylor | B. Soelen | R. White

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