Detection of the Characteristic Pion-Decay Signature in Supernova Remnants

• DOI: 10.1126/science.1231160
• Publication Date: 2013-02-14T20:26:28Z
• Authors: M. Ackermann; M. Ajello; A. Allafort; L. Baldini; J. Ballet; G. Barbiellini; M. G. Baring; D. Bastieri; K. Bechtol; R. Bellazzini; R. D. Blandford; E. D. Bloom; E. Bonamente; A. W. Borgland; E. Bottacini; T. J. Brandt; J. Bregeon; M. Brigida; P. Bruel; R. Buehler; G. Busetto; S. Buson; G. A. Caliandro; R. A. Cameron; P. A. Caraveo; J. M. Casandjian; C. Cecchi; Ö. Çelik; E. Charles; S. Chaty; R. C. G. Chaves; A. Chekhtman; C. C. Cheung; J. Chiang; G. Chiaro; A. N. Cillis; S. Ciprini; R. Claus; J. Cohen-Tanugi; L. R. Cominsky; J. Conrad; S. Corbel; S. Cutini; F. D'Ammando; A. de Angelis; F. de Palma; C. D. Dermer; E. do Couto e Silva; P. S. Drell; A. Drlica-Wagner; L. Falletti; C. Favuzzi; E. C. Ferrara; A. Franckowiak; Y. Fukazawa; S. Funk; P. Fusco; F. Gargano; S. Germani; N. Giglietto; P. Giommi; F. Giordano; M. Giroletti; T. Glanzman; G. Godfrey; I. A. Grenier; M.-H. Grondin; J. E. Grove; S. Guiriec; D. Hadasch; Y. Hanabata; A. K. Harding; M. Hayashida; K. Hayashi; E. Hays; J. W. Hewitt; A. B. Hill; R. E. Hughes; M. S. Jackson; T. Jogler; G. Jóhannesson; A. S. Johnson; T. Kamae; J. Kataoka; J. Katsuta; J. Knödlseder; M. Kuss; J. Lande; S. Larsson; L. Latronico; M. Lemoine-Goumard; F. Longo; F. Loparco; M. N. Lovellette; P. Lubrano; G. M. Madejski; F. Massaro; M. Mayer; M. N. Mazziotta; J. E. McEnery; J. Mehault; P. F. Michelson; R. P. Mignani; W. Mitthumsiri; T. Mizuno; A. A. Moiseev; M. E. Monzani; A. Morselli; I. V. Moskalenko; S. Murgia; T. Nakamori; R. Nemmen; E. Nuss; M. Ohno; T. Ohsugi; N. Omodei; M. Orienti; E. Orlando; J. F. Ormes; D. Paneque; J. S. Perkins; M. Pesce-Rollins; F. Piron; G. Pivato; S. Rainò; R. Rando; M. Razzano; S. Razzaque; A. Reimer; O. Reimer; S. Ritz; C. Romoli; M. Sánchez-Conde; A. Schulz; C. Sgrò; P. E. Simeon; E. J. Siskind; D. A. Smith; G. Spandre; P. Spinelli; F. W. Stecker; A. W. Strong; D. J. Suson; H. Tajima; H. Takahashi; T. Takahashi; T. Tanaka; J. G. Thayer; J. B. Thayer; D. J. Thompson; S. E. Thorsett; L. Tibaldo; O. Tibolla; M. Tinivella; E. Troja; Y. Uchiyama; T. L. Usher; J. Vandenbroucke; V. Vasileiou; G. Vianello; V. Vitale; A. P. Waite; M. Werner; B. L. Winer; K. S. Wood; M. Wood; R. Yamazaki; Z. Yang; S. Zimmer
• Keywords: High Energy Astrophysical Phenomena (astro-ph.HE); [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]; [SDU.ASTR.HE] Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]; [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]; FOS: Physical sciences; 500; 530; Supernova Remnant; Astrophysics - Astrophysics of Galaxies; 01 natural sciences; Cosmic Rays; Supernova Remnants; Cosmic Rays; Astrophysics of Galaxies (astro-ph.GA); 0103 physical sciences; Astrophysics - High Energy Astrophysical Phenomena; Pion-Decay Signature, Supernova Remnants; [PHYS.ASTR.HE] Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]; info:eu-repo/classification/ddc/500

Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) the sources of galactic cosmic rays, unequivocal evidence for acceleration protons in these objects is still lacking. When encounter interstellar material, they produce neutral pions, which turn decay into gamma rays. This offers a compelling way detect sites protons. The identification pion-decay has been difficult because high-energy electrons also via bremsstrahlung and inverse Compton scattering. We detected characteristic feature gamma-ray spectra two SNRs, IC 443 W44, with Fermi Large Area Telescope. detection provides direct cosmic-ray SNRs.