Revisiting the Westerlund 2 field with the HESS telescope array

  title={Revisiting the Westerlund 2 field with the HESS telescope array},
  author={The H.E.S.S. Collaboration A. Abramowski and Fabio Acero and Felix Aharonian and A. G. Akhperjanian and Gisela Anton and Anna Barnacka and Ulisses Barres DE Almeida and A. R. Bazer-Bachi and Y Becherini and James T. Becker and Bagmeet Behera and Konrad Bernlohr and Anne Bochow and Catherine Boisson and Julien Bolmont and Pol Bordas and V. Borrel and J. Brucker and F. Brun and P. Brun and Tomasz Bulik and Ingo Busching and Timoth{\'e} Boutelier and S. Casanova and M. Cerruti and Paula M Chadwick and Ald{\'e}e Charbonnier and Ryan C. G. Chaves and A. Cheesebrough and Janet M. Conrad and L. M. Chounet and A. C. Clapson and Nicolas Produit and Matthew Dalton and M. K. Daniel and I. D. Davids and B. Degrange and Christoph Deil and Hugh J. Dickinson and Arache Djannati-Atai and Wilfried F. Domainko and Luke O'c. Drury and Franky Dubois and Guillaume Dubus and Jarosław Dyks and Michal Dyrda and Kathrin Egberts and Peter Eger and P. Espigat and Lisa Fallon and Christian Farnier and Stephen Fegan and Fabrice Feinstein and Milton Virg{\'i}lio Fernandes and A. Fiasson and A. Forster and Gilles Fontaine and Matthias Fussling and Stefano Gabici and Yves A. Gallant and Lucie G'erard and Dennis Gerbig and Berrie Giebels and J. F. Glicenstein and B. Gluck and Philippe Goret and D. Goring and John D. Hague and Daniel Hampf and Marcus Hauser and Sebastian Heinz and G{\"o}tz Heinzelmann and Gilles Henri and German Hermann and J. A. Hinton and A. Hoffmann and W. Hofmann and Petter Hofverberg and M. Holleran and Silke Hoppe and Dieter Horns and A. Jacholkowska and Ocker C. de Jager and Constanze Jahn and Ira Jung and K. Katarzy'nski and Uli Katz and Sarah Kaufmann and Matthias Kerschhaggl and Dmitry Khangulyan and Bruno Kh'elifi and D. Keogh and Dmitry Klochkov and W. Klu'zniak24 and Tanja M. Kneiske and Nu. Komin and K. Kosack and R. Kossakowski and Giovanni Lamanna and J.-P. Lenain and Dirk Lennarz and Thomas Lohse and C.-C. Lu and V. Marandon and Alexandre Marcowith and Julien Masbou and David Maurin and T. J. L. Mccomb and Maria Clara Medina and J. M'ehault and Rafal Moderski and Emmanuel Moulin and Melitta Naumann-Godo and Mathieu de Naurois and Dalibor Nedbal and Daniil Nekrassov and Nelly Nguyen and Brent P. Nicholas and Jacek Niemiec and S. J. Nolan and S. Ohm and J-F. Olive and Emma de O{\~n}a Wilhelmi and B. Opitz and K. J. Orford and Michał Ostrowski and Mike Panter and Manuel Paz Arribas and G. Pedaletti1 and Guy Pelletier and P.-O. Petrucci and S. Pita1 and Gerd Puhlhofer and M. Punch and Andreas Quirrenbach and Martin Raue and Stephen Mark Rayner and A. Reimer and O. Reimer and Matthieu Renaud and Raquel de los Reyes and F. Rieger1 and Joachim Ripken and L. Rob and S. Rosier-Lees and Gavin Rowell and B. Rudak and Cameron B Rulten and J. Ruppel and Felix Ryde and Vardan Sahakian and A. Santangelo and Reinhard Schlickeiser and F. M. Schock and A. R. Schonwald and U. Schwanke and Stefan Schwarzburg and Stefanie Schwemmer and Andreas Shalchi and Iurii Sushch and Marek Sikora and Joanna Skilton and H'elene Sol and Gerrit Spengler and Lukasz Stawarz and Riaan Steenkamp and Christian M. Stegmann and F. Stinzing and Anna Z. Sz{\'o}stek and P. H. Thomas Tam and J-P. Tavernet and R. Terrier and Omar Tibolla and Martin Tluczykont and Kathrin Valerius and Christopher van Eldik and Georges Vasileiadis and Christo Venter and J. P. Vialle and Aion Viana and Pascal Vincent and Matthieu Vivier and Heinrich J. Volk and Francesca Volpe and Serguei Vorobiov and S. J. Wagner and Martin J. Ward and Andrzej A. Zdziarski and Andreas Zech and Hannes-S. Zechlin and Yasuo Fukui and Naoko Furukawa and Akio Ohama and Hidetoshi Sano and J. R. Dawson and Akiko Kawamura},
  journal={Astronomy and Astrophysics},
Aims. Previous observations with the H.E.S.S. telescope array revealed the existence of extended very-high-energy (VHE; E>100 GeV) {\gamma}-ray emission, HESS J1023-575, coincident with the young stellar cluster Westerlund 2. At the time of discovery, the origin of the observed emission was not unambiguously identified, and follow-up observations have been performed to further investigate the nature of this {\gamma}-ray source. Methods. The Carina region towards the open cluster Westerlund 2… 

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