Measurement of Separate Cosmic-Ray Electron and Positron Spectra with the Fermi Large Area Telescope

被引:470
作者
Ackermann, M. [1 ]
Ajello, M. [2 ,3 ]
Allafort, A. [2 ,3 ]
Atwood, W. B. [4 ,5 ]
Baldini, L. [6 ]
Barbiellini, G. [7 ,8 ]
Bastieri, D. [9 ,10 ]
Bechtol, K. [2 ,3 ]
Bellazzini, R. [6 ]
Berenji, B. [2 ,3 ]
Blandford, R. D. [2 ,3 ]
Bloom, E. D. [2 ,3 ]
Bonamente, E. [11 ,12 ]
Borgland, A. W. [2 ,3 ]
Bouvier, A. [4 ,5 ]
Bregeon, J. [6 ]
Brigida, M. [13 ,14 ]
Bruel, P. [15 ]
Buehler, R. [2 ,3 ]
Buson, S. [9 ,10 ]
Caliandro, G. A. [16 ]
Cameron, R. A. [2 ,3 ]
Caraveo, P. A. [17 ]
Casandjian, J. M. [18 ]
Cecchi, C. [11 ,12 ]
Charles, E. [2 ,3 ]
Chekhtman, A. [19 ]
Cheung, C. C. [20 ]
Chiang, J. [2 ,3 ]
Ciprini, S. [12 ,21 ]
Claus, R. [2 ,3 ]
Cohen-Tanugi, J. [22 ]
Conrad, J. [23 ,24 ]
Cutini, S. [25 ]
de Angelis, A. [26 ,27 ]
de Palma, F. [13 ,14 ]
Dermer, C. D. [28 ]
Digel, S. W. [2 ,3 ]
do Couto e Silva, E. [2 ,3 ]
Drell, P. S. [2 ,3 ]
Drlica-Wagner, A. [2 ,3 ]
Favuzzi, C. [13 ,14 ]
Fegan, S. J. [15 ]
Ferrara, E. C. [29 ]
Focke, W. B. [2 ,3 ]
Fortin, P. [15 ]
Fukazawa, Y. [30 ]
Funk, S. [2 ,3 ]
Fusco, P. [13 ,14 ]
Gargano, F. [14 ]
机构
[1] Deutsch Elektronen Synchrotron DESY, D-15738 Zeuthen, Germany
[2] Stanford Univ, Dept Phys, WW Hansen Expt Phys Lab, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94305 USA
[3] Stanford Univ, SLAC Natl Accelerator Lab, Stanford, CA 94305 USA
[4] Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Dept Phys, Santa Cruz, CA 95064 USA
[5] Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA
[6] Ist Nazl Fis Nucl, Sez Pisa, I-56127 Pisa, Italy
[7] Ist Nazl Fis Nucl, Sez Trieste, I-34127 Trieste, Italy
[8] Univ Trieste, Dipartimento Fis, I-34127 Trieste, Italy
[9] Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy
[10] Univ Padua, Dipartimento Fis G Galilei, I-35131 Padua, Italy
[11] Ist Nazl Fis Nucl, Sez Perugia, I-06123 Perugia, Italy
[12] Univ Perugia, Dipartimento Fis, I-06123 Perugia, Italy
[13] Univ Politecn Bari, Dipartimento Fis M Merlin, I-70126 Bari, Italy
[14] Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, Italy
[15] Ecole Polytech, CNRS, IN2P3, Lab Leprince Ringuet, F-91128 Palaiseau, France
[16] Inst Ciencies Espai IEEE CSIC, Barcelona 08193, Spain
[17] INAF Ist Astrofis Spaziale & Fis Cosm, I-20133 Milan, Italy
[18] Univ Paris Diderot, CNRS, IRFU, CEA,Lab AIM,Serv Astrophys,CEA Saclay, F-91191 Gif Sur Yvette, France
[19] Artep Inc, Ellicott City, MD 21042 USA
[20] Natl Acad Sci, Natl Res Council Res Associate, Washington, DC 20001 USA
[21] ASI Sci Data Ctr, I-00044 Frascati, Roma, Italy
[22] Univ Montpellier 2, Lab Univers & Particules Montpellier, CNRS, IN2P3, Montpellier, France
[23] Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden
[24] Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden
[25] Agenzia Spaziale Italiana ASI Sci Data Ctr, I-00044 Frascati, Roma, Italy
[26] Univ Udine, Dipartimento Fis, I-33100 Udine, Italy
[27] Ist Nazl Fis Nucl, Sez Trieste, Grp Collegato Udine, I-33100 Udine, Italy
[28] USN, Res Lab, Div Space Sci, Washington, DC 20375 USA
[29] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA
[30] Hiroshima Univ, Dept Phys Sci, Higashihiroshima, Hiroshima 7398526, Japan
[31] INAF Ist Radioastron, I-40129 Bologna, Italy
[32] Univ Alabama, CSPAR, Huntsville, AL 35899 USA
[33] Kyoto Univ, Grad Sch Sci, Dept Astron, Sakyo Ku, Kyoto 6068502, Japan
[34] Ohio State Univ, Dept Phys, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA
[35] Univ Iceland, Inst Sci, IS-107 Reykjavik, Iceland
[36] Ibaraki Univ, Coll Sci, Mito, Ibaraki 3108512, Japan
[37] Waseda Univ, Res Inst Sci & Engn, Shinjuku Ku, Tokyo 1698555, Japan
[38] IRAP, CNRS, F-31028 Toulouse 4, France
[39] Univ Toulouse, GAHEC, UPS, OMP,IRAP, Toulouse, France
[40] Ist Nazl Fis Nucl, Sez Torino, I-10125 Turin, Italy
[41] Univ Bordeaux 1, CNRS, IN2P3, Ctr Etud Nucl Bordeaux Gradignan, F-33175 Gradignan, France
[42] Univ Maryland, Dept Phys, College Pk, MD 20742 USA
[43] Univ Maryland, Dept Astron, College Pk, MD 20742 USA
[44] CRESST, Greenbelt, MD 20771 USA
[45] Ist Nazl Fis Nucl, Sez Roma Tor Vergata, I-00133 Rome, Italy
[46] Boise State Univ, Dept Phys, Boise, ID 83725 USA
[47] JAXA, Inst Space & Astronaut Sci, Chuo Ku, Sagamihara, Kanagawa 2525210, Japan
[48] Hiroshima Univ, Hiroshima Astrophys Sci Ctr, Higashihiroshima, Hiroshima 7398526, Japan
[49] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany
[50] Univ Denver, Dept Phys & Astron, Denver, CO 80208 USA
关键词
RADIATION; ENERGIES; RATIO; SPECTROMETER; ASYMMETRY; COMPONENT; FRACTION; FLIGHT;
D O I
10.1103/PhysRevLett.108.011103
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
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 Earth's shadow, which is offset in opposite directions for opposite charges due to 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 and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeVare consistent with a fraction that is continuing to rise with energy.
引用
收藏
页数:7
相关论文
共 39 条
  • [1] Fermi large area telescope observations of the cosmic-ray induced γ-ray emission of the Earth's atmosphere
    Abdo, A. A.
    Ackermann, M.
    Ajello, M.
    Atwood, W. B.
    Baldini, L.
    Ballet, J.
    Barbiellini, G.
    Bastieri, D.
    Baughman, B. M.
    Bechtol, K.
    Bellazzini, R.
    Berenji, B.
    Bloom, E. D.
    Bonamente, E.
    Borgland, A. W.
    Bouvier, A.
    Bregeon, J.
    Brez, A.
    Brigida, M.
    Bruel, P.
    Buehler, R.
    Burnett, T. H.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Casandjian, J. M.
    Cecchi, C.
    Celik, Oe
    Charles, E.
    Chekhtman, A.
    Chiang, J.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Conrad, J.
    de Palma, F.
    Digel, S. W.
    do Couto e Silva, E.
    Drell, P. S.
    Dubois, R.
    Dumora, D.
    Farnier, C.
    Favuzzi, C.
    Fegan, S. J.
    Focke, W. B.
    Fortin, P.
    Frailis, M.
    Fukazawa, Y.
    Funk, S.
    [J]. PHYSICAL REVIEW D, 2009, 80 (12):
  • [2] Measurement of the Cosmic Ray e++e- Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope
    Abdo, A. A.
    Ackermann, M.
    Ajello, M.
    Atwood, W. B.
    Axelsson, M.
    Baldini, L.
    Ballet, J.
    Barbiellini, G.
    Bastieri, D.
    Battelino, M.
    Baughman, B. M.
    Bechtol, K.
    Bellazzini, R.
    Berenji, B.
    Blandford, R. D.
    Bloom, E. D.
    Bogaert, G.
    Bonamente, E.
    Borgland, A. W.
    Bregeon, J.
    Brez, A.
    Brigida, M.
    Bruel, P.
    Burnett, T. H.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Carlson, P.
    Casandjian, J. M.
    Cecchi, C.
    Charles, E.
    Chekhtman, A.
    Cheung, C. C.
    Chiang, J.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Cominsky, L. R.
    Conrad, J.
    Cutini, S.
    Dermer, C. D.
    de Angelis, A.
    de Palma, F.
    Digel, S. W.
    Di Bernardo, G.
    do Couto e Silva, E.
    Drell, P. S.
    Dubois, R.
    Dumora, D.
    Edmonds, Y.
    [J]. PHYSICAL REVIEW LETTERS, 2009, 102 (18)
  • [3] In-flight measurement of the absolute energy scale of the Fermi Large Area Telescope
    Ackermann, M.
    Ajello, M.
    Allafort, A.
    Atwood, W. B.
    Axelsson, M.
    Baldini, L.
    Barbiellini, G.
    Bastieri, D.
    Bechtol, K.
    Bellazzini, R.
    Berenji, B.
    Bloom, E. D.
    Bonamente, E.
    Borgland, A. W.
    Bouvier, A.
    Bregeon, J.
    Brez, A.
    Brigida, M.
    Bruel, P.
    Buehler, R.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Casandjian, J. M.
    Cecchi, C.
    Charles, E.
    Chekhtman, A.
    Chiang, J.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Cutini, S.
    de Palma, F.
    Dermer, C. D.
    Digel, S. W.
    do Couto e Silva, E.
    Drell, P. S.
    Drlica-Wagner, A.
    Dubois, R.
    Enoto, T.
    Falletti, L.
    Favuzzi, C.
    Fegan, S. J.
    Focke, W. B.
    Fortin, P.
    Fukazawa, Y.
    Funk, S.
    Fusco, P.
    Gargano, F.
    [J]. ASTROPARTICLE PHYSICS, 2012, 35 (06) : 346 - 353
  • [4] Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV
    Ackermann, M.
    Ajello, M.
    Atwood, W. B.
    Baldini, L.
    Ballet, J.
    Barbiellini, G.
    Bastieri, D.
    Baughman, B. M.
    Bechtol, K.
    Bellardi, F.
    Bellazzini, R.
    Belli, F.
    Berenji, B.
    Blandford, R. D.
    Bloom, E. D.
    Bogart, J. R.
    Bonamente, E.
    Borgland, A. W.
    Brandt, T. J.
    Bregeon, J.
    Brez, A.
    Brigida, M.
    Bruel, P.
    Buehler, R.
    Burnett, T. H.
    Busetto, G.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Carlson, P.
    Carrigan, S.
    Casandjian, J. M.
    Ceccanti, M.
    Cecchi, C.
    Celik, Oe
    Charles, E.
    Chekhtman, A.
    Cheung, C. C.
    Chiang, J.
    Cillis, A. N.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Conrad, J.
    Corbet, R.
    DeKlotz, M.
    Dermer, C. D.
    de Angelis, A.
    de Palma, F.
    [J]. PHYSICAL REVIEW D, 2010, 82 (09):
  • [5] Cosmic-Ray Electron Flux Measured by the PAMELA Experiment between 1 and 625 GeV
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bongi, M.
    Bonvicini, V.
    Borisov, S.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carbone, R.
    Carlson, P.
    Casolino, M.
    Castellini, G.
    Consiglio, L.
    De Pascale, M. P.
    De Santis, C.
    De Simone, N.
    Di Felice, V.
    Galper, A. M.
    Gillard, W.
    Grishantseva, L.
    Jerse, G.
    Karelin, A. V.
    Koldashov, S. V.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malakhov, V.
    Malvezzi, V.
    Marcelli, L.
    Mayorov, A. G.
    Menn, W.
    Mikhailov, V. V.
    Mocchiutti, E.
    Monaco, A.
    Mori, N.
    Nikonov, N.
    Osteria, G.
    Palma, F.
    Papini, P.
    Pearce, M.
    Picozza, P.
    Pizzolotto, C.
    Ricci, M.
    Ricciarini, S. B.
    Rossetto, L.
    [J]. PHYSICAL REVIEW LETTERS, 2011, 106 (20)
  • [6] PAMELA Measurements of Cosmic-Ray Proton and Helium Spectra
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bonechi, L.
    Bongi, M.
    Bonvicini, V.
    Borisov, S.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carbone, R.
    Carlson, P.
    Casolino, M.
    Castellini, G.
    Consiglio, L.
    De Pascale, M. P.
    De Santis, C.
    De Simone, N.
    Di Felice, V.
    Galper, A. M.
    Gillard, W.
    Grishantseva, L.
    Jerse, G.
    Karelin, A. V.
    Koldashov, S. V.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malakhov, V.
    Malvezzi, V.
    Marcelli, L.
    Mayorov, A. G.
    Menn, W.
    Mikhailov, V. V.
    Mocchiutti, E.
    Monaco, A.
    Mori, N.
    Nikonov, N.
    Osteria, G.
    Palma, F.
    Papini, P.
    Pearce, M.
    Picozza, P.
    Pizzolotto, C.
    Ricci, M.
    Ricciarini, S. B.
    [J]. SCIENCE, 2011, 332 (6025) : 69 - 72
  • [7] A statistical procedure for the identification of positrons in the PAMELA experiment
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bonechi, L.
    Bongi, M.
    Bonvicini, V.
    Borisov, S.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carbone, R.
    Carlson, P.
    Casolino, M.
    Castellini, G.
    Consiglio, L.
    De Pascale, M. P.
    De Santis, C.
    De Simone, N.
    Di Felice, V.
    Galper, A. M.
    Gillard, W.
    Grishantseva, L.
    Hofverberg, P.
    Jerse, G.
    Koldashov, S. V.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malvezzi, V.
    Marcelli, L.
    Menn, W.
    Mikhailov, V. V.
    Mocchiutti, E.
    Monaco, A.
    Mori, N.
    Nikonov, N.
    Osteria, G.
    Papini, P.
    Pearce, M.
    Picozza, P.
    Ricci, M.
    Ricciarini, S. B.
    Rossetto, L.
    Simon, M.
    Sparvoli, R.
    Spillantini, P.
    [J]. ASTROPARTICLE PHYSICS, 2010, 34 (01) : 1 - 11
  • [8] An anomalous positron abundance in cosmic rays with energies 1.5-100 GeV
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bonechi, L.
    Bongi, M.
    Bonvicini, V.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carlson, P.
    Casolino, M.
    Castellini, G.
    De Pascale, M. P.
    De Rosa, G.
    De Simone, N.
    Di Felice, V.
    Galper, A. M.
    Grishantseva, L.
    Hofverberg, P.
    Koldashov, S. V.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malvezzi, V.
    Marcelli, L.
    Menn, W.
    Mikhailov, V. V.
    Mocchiutti, E.
    Orsi, S.
    Osteria, G.
    Papini, P.
    Pearce, M.
    Picozza, P.
    Ricci, M.
    Ricciarini, S. B.
    Simon, M.
    Sparvoli, R.
    Spillantini, P.
    Stozhkov, Y. I.
    Vacchi, A.
    Vannuccini, E.
    Vasilyev, G.
    Voronov, S. A.
    Yurkin, Y. T.
    Zampa, G.
    Zampa, N.
    [J]. NATURE, 2009, 458 (7238) : 607 - 609
  • [9] GEANT4-a simulation toolkit
    Agostinelli, S
    Allison, J
    Amako, K
    Apostolakis, J
    Araujo, H
    Arce, P
    Asai, M
    Axen, D
    Banerjee, S
    Barrand, G
    Behner, F
    Bellagamba, L
    Boudreau, J
    Broglia, L
    Brunengo, A
    Burkhardt, H
    Chauvie, S
    Chuma, J
    Chytracek, R
    Cooperman, G
    Cosmo, G
    Degtyarenko, P
    Dell'Acqua, A
    Depaola, G
    Dietrich, D
    Enami, R
    Feliciello, A
    Ferguson, C
    Fesefeldt, H
    Folger, G
    Foppiano, F
    Forti, A
    Garelli, S
    Giani, S
    Giannitrapani, R
    Gibin, D
    Cadenas, JJG
    González, I
    Abril, GG
    Greeniaus, G
    Greiner, W
    Grichine, V
    Grossheim, A
    Guatelli, S
    Gumplinger, P
    Hamatsu, R
    Hashimoto, K
    Hasui, H
    Heikkinen, A
    Howard, A
    [J]. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, 2003, 506 (03) : 250 - 303
  • [10] Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01
    Aguilar, M.
    Alcaraz, J.
    Allaby, J.
    Alpat, B.
    Ambrosi, G.
    Anderhub, H.
    Ao, L.
    Arefiev, A.
    Azzarello, P.
    Baldini, L.
    Basile, M.
    Barancourt, D.
    Barao, F.
    Barbier, G.
    Barreira, G.
    Battiston, R.
    Becker, R.
    Becker, U.
    Bellagamba, L.
    Bene, P.
    Berdugo, J.
    Berges, R.
    Bertucci, B.
    Biland, A.
    Blasko, S.
    Boella, G.
    Boschini, M.
    Bourquin, M.
    Brocco, L.
    Bruni, G.
    Buenerd, M.
    Burger, J. D.
    Burger, W. J.
    Cai, X. D.
    Camps, C.
    Cannarsa, P.
    Capell, M.
    Cardano, F.
    Casadei, D.
    Casaus, J.
    Castellini, G.
    Chang, Y. H.
    Chen, H. F.
    Chen, H. S.
    Chen, Z. G.
    Chernoplekov, N. A.
    Chiueh, T. H.
    Cho, K.
    Choi, M. J.
    Choi, Y. Y.
    [J]. PHYSICS LETTERS B, 2007, 646 (04) : 145 - 154