title={THE 2012 FLARE OF PG 1553+113 SEEN WITH H.E.S.S. AND FERMI-LAT},
  author={Attila Abramowski and Felix Aharonian and Faical Ait Benkhali and A. G. Akhperjanian and Ekrem Oǧuzhan Ang{\"u}ner and Michael Backes and Shangkari Balenderan and Arnim Balzer and Anna Barnacka and Y Becherini and Julia K. Becker Tjus and David Berge and Sabrina Bernhard and Konrad Bernl{\"o}hr and Emrah Birsin and Jonathan Biteau and Markus B{\"o}ttcher and Catherine Boisson and Julien Bolmont and P. Bordas and Johan Bregeon and François Brun and P. Brun and Mark Bryan and Tomasz Bulik and Svenja Carrigan and Sabrina Casanova and Paula M Chadwick and Nachiketa Chakraborty and R. Chalme-Calvet and Ryan C. G. Chaves and M C Chretien and Sergio Colafrancesco and Gabriele Cologna and Janet M. Conrad and Camille Couturier and Y. Cui and Matthew Dalton and I. D. Davids and B. Degrange and Christoph Deil and P. deWilt and Arache Djannati-Ata{\"i} and Wilfried F. Domainko and Axel Donath and Luke O'c. Drury and Guillaume Dubus and Kathleen Dutson and Jarosław Dyks and Michal Dyrda and T. D. P. Edwards and Kathrin Egberts and Peter Eger and P. Espigat and Christian Farnier and Stephen J. Fegan and Fabrice Feinstein and Milton Virg{\'i}lio Fernandes and Diane Fernandez and A. Fiasson and Gilles Fontaine and Andreas F{\"o}rster and Matthias F{\"u}{\ss}ling and Stefano Gabici and Michael Gajdus and Yves A. Gallant and Tania Garrigoux and G. Giavitto and Berrie Giebels and J. F. Glicenstein and Daniel Gottschall and M.-H. Grondin and Mira Grudzi'nska and D. Hadsch and S. H{\"a}ffner and Joachim Hahn and J. Harris and G{\"o}tz Heinzelmann and Gilles Henri and German Hermann and Olivier Hervet and Andreas Hillert and J. A. Hinton and W. Hofmann and Petter Hofverberg and Markus Holler and Dieter Horns and Alex Ivascenko and A. Jacholkowska and Constanze Jahn and Marek Jamrozy and Mateusz Janiak and Felix Jankowsky and Ira Jung and Max Anton Kastendieck and K. Katarzy'nski and Uli Katz and Sarah Kaufmann and Bruno Kh'elifi and Michel Kieffer and S. Klepser and Dmitry Klochkov and Wlodek Klu'zniak and D. Kolitzus and Nu. Komin and K. Kosack and S. Krakau and Fabien Krayzel and Petrus Paulus Kr{\"u}ger and H'elene Laffon and Giovanni Lamanna and Julien Lefaucheur and V. Lefranc and Anne Lemi{\`e}re and Marianne Lemoine-Goumard and J.-P. Lenain and Thomas Lohse and Anatoli N. Lopatin and C.-C. Lu and V. Marandon and Alexandre Marcowith and Ramin Marx and Gilles Maurin and Nigel I. Maxted and M. G. F. Mayer and T. J. L. Mccomb and J. M{\'e}hault and Petrus J. Meintjes and Ulf Menzler and Manuel Meyer and Alison Mitchell and Rafal Moderski and Mahmoud Mohamed and Karen Salom{\'e} Caballero Mora and Emmanuel Moulin and T. Murach and Mathieu de Naurois and Jacek Niemiec and S. J. Nolan and Louise Beth Oakes and Hirokazu Odaka and S. Ohm and B. Opitz and Michał Ostrowski and I. Oya and Mike Panter and R. D. Parsons and M. Paz Arribas and Nikki Pekeur and Guy Pelletier and J. Valero P{\'e}rez and P. Petrucci and Bernard Peyaud and Santiago Pita and Helen Poon and Gerd P{\"u}hlhofer and M. Punch and Andreas Quirrenbach and S. Raab and Ignasi Reichardt and Anita Reimer and O. Reimer and Matthieu Renaud and Raquel De Los Reyes and Frank M. Rieger and L. Rob and Carlo Romoli and S. Rosier-Lees and Gavin Rowell and B. Rudak and Cameron B Rulten and Vardan Sahakian and David {\vS}{\'a}lek and D. A. Sanchez and A. Santangelo and Reinhard Schlickeiser and Fabian Sch{\"u}ssler and Alex Schulz and U. Schwanke and Stefan Schwarzburg and Stefanie Schwemmer and H'elene Sol and Felix Spanier and Gerrit Spengler and F. Spies and Łukasz Stawarz and Riaan Steenkamp and Christian M. Stegmann and F. Stinzing and Kornelia Stycz and Iurii Sushch and J-P. Tavernet and Thomas Tavernier and A. M. Taylor and R. Terrier and Martin Tluczykont and Cyril Trichard and Kathrin Valerius and C. van Eldik and Brian van Soelen and Georges Vasileiadis and J. Veh and Christo Venter and Aion Viana and Pascal Vincent and Jacco Vink and H. J. V{\"o}lk and Francesca Volpe and Martine Vorster and Thomas Vuillaume and Philipp Wagner and Robert M. Wagner and Martin J. Ward and Matthias Weidinger and Quirin Weitzel and R. M. White and Alicja Wierzcholska and Philipp Willmann and A. W{\"o}rnlein and Denis Wouters and R. Yang and V'ictor Zabalza and D. N. Zaborov and Michael Zacharias and Andrzej A. Zdziarski and Andreas Zech and Hannes-S. Zechlin},
  journal={The Astrophysical Journal},
Very high energy (VHE, E > 100 GeV) γ-ray flaring activity of the high-frequency peaked BL Lac object PG 1553+113 has been detected by the H.E.S.S. telescopes. The flux of the source increased by a factor of 3 during the nights of 2012 April 26 and 27 with respect to the archival measurements with a hint of intra-night variability. No counterpart of this event has been detected in the Fermi-Large Area Telescope data. This pattern is consistent with VHE γ-ray flaring being caused by the… 

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HESS observations and VLT spectroscopy of PG 1553+113

AIMS: The properties of the very high energy (VHE; E>100 GeV) gamma-ray emission from the high-frequency peaked BL Lac PG 1553+113 are investigated. An attempt is made to measure the currently


We present the results of five years (2005–2009) of MAGIC observations of the BL Lac object PG 1553+113 at very high energies (VHEs; E > 100 GeV). Power-law fits of the individual years are


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The -ray emission above 250 GeV from the BL Lac object Markarian 421 was observed by the CAT Cherenkov imaging telescope between December, 1996, and June, 2000. In 1998, the source produced a series

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The extragalactic background light (EBL) is the diffuse radiation with the second highest energy density in the Universe after the cosmic microwave background. The aim of this study is the

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TeV blazars are known as prominent nonthermal emitters across the entire electromagnetic spectrum with their photon power peaking in the X-ray and TeV bands. If distant, absorption of γ-ray photons


We present new moderate-resolution, far-ultraviolet spectra from the Hubble Space Telescope/Cosmic Origins Spectrograph (HST/COS) of the BL Lac object 1ES 1553+113 covering the wavelength range 1135