REPORTS Energy in the United States; Commissariat à l’Energie Sezione di Padova, I-35131 Padova, Italy. 8Dipartimento di gineering, Waseda University, 3-4-1, Okubo, Shinjuku, Tokyo Atomique et aux Énergies Alternatives, Institut de Recherche Fisica “G. Galilei,” Università di Padova, I-35131 Padova, Italy. 169-8555, Japan. 41CNRS, Research Institute in Astrophysics sur les Lois Fondamentales de l’Univers (CEA/IRFU) and 9Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 and Planetology (IRAP), F-31028 Toulouse cedex 4, France. Institut National de Physique Nucléaire et de Physique des Pisa, Italy. 10Istituto Nazionale di Fisica Nucleare, Sezione di 42Galaxies, Astrophysique des Hautes Energies et Cosmologie, Particules, Centre National de la Recherche Scientifique Perugia, I-06123 Perugia, Italy. 11Dipartimento di Fisica, Université de Toulouse, UPS-OMP, IRAP, Toulouse, France. (IN2P3/CNRS) in France; Agenzia Spaziale Italiana (ASI) and Università degli Studi di Perugia, I-06123 Perugia, Italy. 43Istituto Nazionale di Fisica Nucleare, Sezioine di Torino, I- Istituto Nazionale di Fisica Nucleare (INFN) in Italy; Ministry 12Dipartimento di Fisica “M. Merlin” dell’Università e del Poli- 10125 Torino, Italy. 44Yukawa Institute for Theoretical Physics, of Education, Culture, Sports, Science, and Technology tecnico di Bari, I-70126 Bari, Italy. 13Istituto Nazionale di Fisica Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto (MEXT), Energy Accelerator Research Organization (KEK), and Nucleare, Sezione di Bari, 70126 Bari, Italy. 14Laboratoire 606-8502, Japan. 45Department of Physics and Department of Japan Aerospace Exploration Agency (JAXA) in Japan; Leprince-Ringuet, École Polytechnique, CNRS/IN2P3, Palaiseau, Astronomy, University of Maryland, College Park, MD 20742, and the K. A. Wallenberg Foundation, Swedish Research France. 15Institut de Ciències de l’Espai (IEEE-CSIC), Campus USA. 46Istituto Nazionale di Fisica Nucleare, Sezione di Roma Council, and National Space Board in Sweden. Additional UAB, 08193 Barcelona, Spain. 16Columbia Astrophysics Labo- “Tor Vergata,” I-00133 Roma, Italy. 47Department of Physics, support from Istituto Nazionale di Astrofisica (INAF) in ratory, Columbia University, New York, NY 10027, USA. Boise State University, Boise, ID 83725, USA. 48Hiroshima Italy and Centre National d’Etudes Spaciales (CNES) in France 17INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, I-20133 Astrophysical Science Center, Hiroshima University, Higashi- for science analysis during the operations phase is also Milano, Italy. 18NASA Goddard Space Flight Center, Greenbelt, Hiroshima, Hiroshima 739-8526, Japan. 49Institute of Space and gratefully acknowledged. The Nançay Radio Observatory is MD 20771, USA. 19Center for Research and Exploration in Astronautical Science, JAXA, 3-1-1 Yoshinodai, Chuo-ku, operated by the Paris Observatory, associated with the French Space Science and Technology (CRESST) and NASA Goddard Sagamihara, Kanagawa 252-5210, Japan. 50Max-Planck-Institut CNRS. The Lovell Telescope is owned and operated by the Space Flight Center, Greenbelt, MD 20771, USA. 20Department für Extraterrestrische Physik, 85748 Garching, Germany. 51Max- University of Manchester as part of the Jodrell Bank Centre for of Physics and Center for Space Sciences and Technology, Planck-Institut für Physik, D-80805 München, Germany. Astrophysics with support from the Science and Technology University of Maryland Baltimore County, Baltimore, MD 52National Radio Astronomy Observatory (NRAO), Charlottes- Facilities Council of the United Kingdom. Fermi LAT data, 21250, USA. 21Artep Inc., 2922 Excelsior Springs Court, Ellicott ville, VA 22903, USA. 53Institut fürAstro- und Teilchenphysik and g-ray diffuse models, and radio pulsar ephemeris are City, MD 21042, USA. 22National Research Council Research Institut für Theoretische Physik, Leopold-Franzens-Universität available from the Fermi Science Support Center (http:// Associate, National Academy of Sciences, Washington, DC Innsbruck, A-6020 Innsbruck, Austria. 54Department of Physics, fermi.gsfc.nasa.gov/ssc/data/access). M.L.-G. was funded by 20001, USA. 23Agenzia Spaziale Italiana (ASI) Science Data University of Washington, Seattle, WA 98195–1560, USA. contract ERC-StG-259391 from the European Community. Center, I-00044 Frascati (Roma), Italy. 24Laboratoire de Phys- 55NYCB Real-Time Computing Inc., Lattingtown, NY 11560– E.T. is a NASA Postdoctoral Program Fellow. 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