Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope gamma-Ray Observations of Earth's Limb

Journal article


Publication Details

Author(s): Ackermann M, Ajello M, Albert A, Allafort A, Baldini L, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Blandford RD, Bloom ED, Bonamente E, Bottacini E, Bouvier A, Brandt TJ, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Cecchi C, Charles E, Chaves RCG, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dalton M, D'Ammando F, de Angelis A, de Palma F, Dermer CD, Digel SW, Di Venere L, do Couto e Silva E, Drell PS, Drlica-Wagner A, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gomez-Vargas GA, Grenier IA, Grove JE, Guiriec S, Gustafsson M, Hadasch D, Hanabata Y, Harding AK, Hayashida M, Hayashi K, Hewitt JW, Horan D, Hou X, Hughes RE, Inoue Y, Jackson MS, Jogler T, Johannesson G, Johnson AS, Kamae T, Kawano T, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lovellette MN, Lubrano P, Mayer M, Mazziotta MN, McEnery JE, Mehault J, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nemmen R, Nuss E, Ohsugi T, Okumura A, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Ritz S, Roth M, Schaal M, Schulz A, Sgro C, Siskind EJ, Spandre G, Spinelli P, Strong AW, Takahashi H, Takeuchi Y, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tinivella M, Torres DF, Tosti G, Troja E, Tronconi V, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Werner M, Winer BL, Wood KS, Wood M, Yang Z
Journal: Physical Review Letters
Publisher: American Physical Society
Publication year: 2014
Volume: 112
ISSN: 0031-9007


Abstract


Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the gamma-ray emission from Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range similar to 90 GeV-6 TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68 +/- 0.04 and 2.61 +/- 0.08 above similar to 200 GeV, respectively.



FAU Authors / FAU Editors

Funk, Stefan Prof. Dr.
Lehrstuhl für Physik


External institutions with authors

AlbaNova University Centre / Kungliga Tekniska Högskolan AlbaNova Universitetscentrum
Center for Research and Exploration in Space Science & Technology (CRESST)
Deutsches Elektronen-Synchrotron DESY
École Polytechnique - Université Paris-Saclay
Fermi National Accelerator Laboratory (Fermilab)
George Mason University
Hiroshima University
Institució Catalana de Recerca i Estudis Avançats (ICREA) / Catalan Institution for Research and Advanced Studies
Institut de Ciències de l'Espai (ICE)
Italian Space Agency / Agenzia Spaziale Italiana (ASI)
Japan Aerospace eXploration Agency (JAXA)
Mahidol University / มหาวิทยาลัยมหิดล
Max-Planck-Institut für extraterrestrische Physik (MPE) / Max Planck Institute for Extraterrestrial Physics
Nagoya University / 名古屋大学
National Aeronautics and Space Administration (NASA)
National Institute for Astrophysics / Istituto Nazionale Astrofisica (INAF)
National Institute for Nuclear Physics / Istituto Nazionale di Fisica Nucleare (INFN)
NYCB Real-Time Computing, Inc.
Ohio State University
Politecnico di Bari
Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH)
Stanford University
Stockholm University / Stockholms universitet
Universidad Autónoma de Madrid (UAM)
Università degli Studi di Roma 'Tor Vergata'
University of California, Berkeley
University of California Santa Cruz
University of Iceland (UI)
University of Johannesburg
University of Montpellier / Université Montpellier
University of Padua
University of Paris 7 - Denis Diderot / Université Paris VII Denis Diderot
University of Tokyo
University of Toulouse
University of Udine / Università degli Studi di Udine
U.S. Naval Research Laboratory
Waseda University / 早稲田大学


How to cite

APA:
Ackermann, M., Ajello, M., Albert, A., Allafort, A., Baldini, L., Barbiellini, G.,... Yang, Z. (2014). Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope gamma-Ray Observations of Earth's Limb. Physical Review Letters, 112. https://dx.doi.org/10.1103/PhysRevLett.112.151103

MLA:
Ackermann, M., et al. "Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope gamma-Ray Observations of Earth's Limb." Physical Review Letters 112 (2014).

BibTeX: 

Last updated on 2018-02-07 at 09:23