Skip to Main content Skip to Navigation
Journal articles

Measurement of separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope

Markus Ackermann Marco Ajello A. Allafort W. B. Atwood Luca Baldini Guido Barbiellini D. Bastieri K. Bechtol R. Bellazzini B. Berenji R. D. Blandford E. D. Bloom E. Bonamente A.W. Borgland A. Bouvier J. Bregeon M. Brigida Pascal Bruel 1 R. Buehler S. Buson G. A. Caliandro R. A. Cameron P. A. Caraveo J. M. Casandjian 2 C. Cecchi E. Charles A. Chekhtman C. C. Cheung J. Chiang S. Ciprini R. Claus J. Cohen-Tanugi 3 J. Conrad S. Cutini A. de Angelis F. de Palma C. D. Dermer S.W. Digel E. Do Couto E Silva P. S. Drell A. Drlica-Wagner C. Favuzzi S. J. Fegan 1 E. C. Ferrara W. B. Focke P. Fortin 1 Y. Fukazawa S. Funk P. Fusco F. Gargano D. Gasparrini S. Germani N. Giglietto P. Giommi F. Giordano M. Giroletti T. Glanzman G. Godfrey I. A. Grenier 2 J. E. Grove S. Guiriec M. Gustafsson D. Hadasch A. K. Harding M. Hayashida R. E. Hughes G. Jo'Hannesson A. S. Johnson T. Kamae H. Katagiri J. Kataoka J. Kno¨dlseder M. Kuss J. Lande L. Latronico M. Lemoine-Goumard 4 M. Llena Garde F. Longo F. Loparco M. N. Lovellette P. Lubrano G. M. Madejski M. N. Mazziotta J. E. Mcenery P. F. Michelson W. Mitthumsiri T. Mizuno A. A. Moiseev C. Monte M. E. Monzani A. Morselli I.V. Moskalenko S. Murgia T. Nakamori P. L. Nolan J. P. Norris E. Nuss 3 M. Ohno T. Ohsugi A. Okumura N. Omodei E. Orlando J. F. Ormes M. Ozaki D. Paneque D. Parent M. Pesce-Rollins M. Pierbattista 2 F. Piron 3 G. Pivato T.A. Porter S. Raino' R. Rando M. Razzano S. Razzaque A. Reimer O. Reimer T. Reposeur 4 S. Ritz R.W. Romani M. Roth H. F.-W. Sadrozinski C. Sbarra T. L. Schalk C. Sgro' E. J. Siskind G. Spandre P. Spinelli A.W. Strong H. Takahashi T. Takahashi T. Tanaka J. G. Thayer J. B. Thayer L. Tibaldo M. Tinivella D. F. Torres G. Tosti E. Troja Y. Uchiyama T. L. Usher J. Vandenbroucke V. Vasileiou 3 G. Vianello V. Vitale A. P. Waite B. L. Winer K. S. Wood M. Wood Z. Yang S. Zimmer
Abstract : We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting the Earth's shadow, which is offset in opposite directions for opposite charges due to the Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 GeV and 200 GeV. We confirm that the fraction rises with energy in the 20--100 GeV range and determine for the first time that it continues to rise between 100 and 200 GeV.
Complete list of metadatas

http://hal.in2p3.fr/in2p3-00665926
Contributor : Nathalie Martin <>
Submitted on : Friday, February 3, 2012 - 11:13:54 AM
Last modification on : Saturday, April 11, 2020 - 2:10:33 AM

Links full text

Identifiers

Citation

Markus Ackermann, Marco Ajello, A. Allafort, W. B. Atwood, Luca Baldini, et al.. Measurement of separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Physical Review Letters, American Physical Society, 2012, 108, pp.0111103. ⟨10.1103/PhysRevLett.108.011103⟩. ⟨in2p3-00665926⟩

Share

Metrics

Record views

551