# Discovery of TeV gamma-ray emission toward supernova remnant SNR G78.2+2.1

@article{Aliu2013DiscoveryOT,
title={Discovery of TeV gamma-ray emission toward supernova remnant SNR G78.2+2.1},
author={Ester Aliu and Simon Archambault and Timothy C. Arlen and T. Aune and Matthias Beilicke and W. Benbow and R. Bird and A. Bouvier and Stella Bradbury and James Henry Buckley and Viatcheslav Bugaev and Karen Lynn Byrum and A. Cannon and Andrea Cesarini and L. Ciupik and Edward Robert Collins-Hughes and Michael P. Connolly and Wei Wei Cui and R. Dickherber and Charles Lewis Duke and Jonathan Dumm and Vikram V. Dwarkadas and M. Errando and Abraham D. Falcone and S. Federici and Qi Feng and John Park Finley and Gary Finnegan and Lucy Fortson and A. Furniss and Nicola Galante and Daniel Gall and G. H. Gillanders and Sagar Godambe and Eric V. Gotthelf and Sean Griffin and Jeff Grube and Geza Gyuk and David Hanna and Jamie Holder and H. Huan and Gareth Hughes and Thomas Brian Humensky and Philip Kaaret and Niklas Karlsson and M. P. Kertzman and Yerbol Farkhatuly Khassen and D. Kieda and Henric Krawczynski and Frank Krennrich and Matthew J. Lang and Ki‐Suk Lee and A. S. Madhavan and Gernot Maier and P. Majumdar and Steven McArthur and A. McCann and John P. Millis and Patrick Moriarty and Reshmi Mukherjee and Tim Nelson and A. O'Faol'ain de Bhr'oithe and R. A. Ong and Matthew R. Orr and A. N. Otte and Dirk Pandel and Nahee Park and Jeremy S. Perkins and Martin Pohl and Alexis Popkow and Heike Prokoph and Joseph F. Quinn and K. Ragan and L. C. Reyes and Philip T. Reynolds and E. Roache and Harry J. Rose and J. Ruppel and D. B. Saxon and Martin Schroedter and Glenn H. Sembroski and G. D. cSenturk and C. Skole and Igor Telezhinsky and G. Tevsi'c and Mark Theiling and S. Thibadeau and K. Tsurusaki and Joshua Tyler and Angelo Varlotta and Vladimir V. Vassiliev and Stephane Vincent and Scott Patrick Wakely and John E. Ward and Trevor C. Weekes and Amanda J. Weinstein and Thomas Weisgarber and Roman Welsing and D. A. Williams and Benjamin Zitzer},
journal={The Astrophysical Journal},
year={2013},
volume={770},
pages={93}
}
We report the discovery of an unidentified, extended source of very-high-energy gamma-ray emission, VER J2019+407, within the radio shell of the supernova remnant SNR G78.2+2.1, using 21.4 hr of data taken by the VERITAS gamma-ray observatory in 2009. These data confirm the preliminary indications of gamma-ray emission previously seen in a two-year (2007-2009) blind survey of the Cygnus region by VERITAS. VER J2019+407, which is detected at a post-trials significance of 7.5 standard deviations… Expand

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