A Cocoon of Freshly Accelerated Cosmic Rays Detected by Fermi in the Cygnus Superbubble

  title={A Cocoon of Freshly Accelerated Cosmic Rays Detected by Fermi in the Cygnus Superbubble},
  author={Markus Ackermann and Marco Ajello and Alice Allafort and Luca Baldini and Jean Ballet and Guido Barbiellini and Denis Bastieri and Andrea Belfiore and Ronaldo Bellazzini and Bijan Berenji and R. Blandford and Elliott D. Bloom and Emanuele Bonamente and A. W. Borgland and Eugenio Bottacini and Monica Brigida and P. Bruel and Roland Buehler and Silvio Buson and Giuseppe Andrea Caliandro and R. A. Cameron and Patricia A. Caraveo and Jean Marc Casandjian and Claudia Cecchi and A. Chekhtman and C. C. Cheung and James Chiang and Stefano Ciprini and Reitlinger Claus and J. Cohen-Tanugi and Alessandro De Angelis and Francesco de Palma and Charles D. Dermer and E. do Couto e Silva and P. S. Drell and Denis Dumora and Cecilia Favuzzi and Stephen Fegan and W. B. Focke and Pascal D. Fortin and Y. Fukazawa and Piergiorgio Fusco and Fabio Gargano and S Germani and N. Giglietto and F. Giordano and Marcello Giroletti and Tom Glanzman and Gh Godfrey and Isabelle A. Grenier and Lucas Guillemot and S. Guiriec and D. Hadasch and Yoshitaka Hanabata and Alice K. Harding and Morihiro Hayashida and Kazuhito Hayashi and E. Hays and Guðlaugur J{\'o}hannesson and A. S. Johnson and Tuneyoshi Kamae and Hiroyuki Katagiri and Jun Kataoka and M. Kerr and J. Kn{\"o}dlseder and Michael Kuss and Joshua Lande and Luca Latronico and S.-H. Lee and Francesco Longo and Francesco Loparco and B. Lott and Michael N. Lovellette and Pasquale Lubrano and P. G. Martin and Mario Nicola Mazziotta and Julie Mcenery and J. Mehault and P. F. Michelson and W. Mitthumsiri and T. Mizuno and Claudia Del Monte and M. E. Monzani and A. Morselli and Igor V. Moskalenko and Simona Murgia and Melitta Naumann-Godo and P. L. Nolan and J. P. Norris and Eric Nuss and T. Ohsugi and Akira Okumura and E. Orlando and Jonathan F. Ormes and M. Ozaki and D. Paneque and Damien Parent and Melissa Pesce-Rollins and Marco Pierbattista and F. Piron and M. Pohl and D. Yu. Prokhorov and S. Rain{\'o} and Riccardo Rando and Massimiliano Razzano and Thierry Reposeur and Steven M. Ritz and P. M. Saz Parkinson and Carmelo Sgro’ and Eric J. Siskind and P. D. Smith and Paolo Spinelli and A. W. Strong and H. Takahashi and T. Tanaka and J. G. Thayer and Jana Thayer and D. J. Thompson and Luigi Tibaldo and Diego F. Torres and Gino Tosti and Andrea Tramacere and Eleonora Troja and Y. Uchiyama and Justin Vandenbroucke and Vlasios Vasileiou and G. Vianello and Vincenzo Vitale and A. P. Waite and P. Wang and B. L. Winer and Ks S. Wood and Z. Yang and Stephen Zimmer and Sylvain Bontemps},
  pages={1103 - 1107}
Cosmic rays can be accelerated in the cavities carved by the stellar winds created by clusters of massive stars. The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little of their escape from the shock and their evolution through the turbulent medium surrounding massive stars. Gamma rays can probe their spreading through the ambient gas and radiation fields. The Fermi Large Area Telescope (LAT) has… 
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