A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8×106 positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼250 GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.

First result from the alpha magnetic spectrometer on the international space station: Precision measurement of the positron fraction in primary cosmic rays of 0.5-350 gev / M. Aguilar, G. Alberti, B. Alpat, A. Alvino, G. Ambrosi, K. Andeen, H. Anderhub, L. Arruda, P. Azzarello, A. Bachlechner, F. Barao, B. Baret, A. Barrau, L. Barrin, A. Bartoloni, L. Basara, A. Basili, L. Batalha, J. Bates, R. Battiston, J. Bazo, R. Becker, U. Becker, M. Behlmann, B. Beischer, J. Berdugo, P. Berges, B. Bertucci, G. Bigongiari, A. Biland, V. Bindi, S. Bizzaglia, G. Boella, W. De Boer, K. Bollweg, J. Bolmont, B. Borgia, S. Borsini, M.J. Boschini, G. Boudoul, M. Bourquin, P. Brun, M. Buenerd, J. Burger, W. Burger, F. Cadoux, X.D. Cai, M. Capell, D. Casadei, J. Casaus, V. Cascioli, G. Castellini, I. Cernuda, F. Cervelli, M.J. Chae, Y.H. Chang, A.I. Chen, C.R. Chen, H. Chen, G.M. Cheng, H.S. Chen, L. Cheng, N. Chernoplyiokov, A. Chikanian, E. Choumilov, V. Choutko, C.H. Chung, C. Clark, R. Clavero, G. Coignet, V. Commichau, C. Consolandi, A. Contin, C. Corti, M.T. Costado Dios, B. Coste, D. Crespo, Z. Cui, M. Dai, C. Delgado, S. Della Torre, B. Demirkoz, P. Dennett, L. Derome, S. Di Falco, X.H. Diao, A. Diago, L. Djambazov, C. Diaz, P. Von Doetinchem, W.J. Du, J.M. Dubois, R. Duperay, M. Duranti, D. D'Urso, A. Egorov, A. Eline, F.J. Eppling, T. Eronen, J. Van Es, H. Esser, A. Falvard, E. Fiandrini, A. Fiasson, E. Finch, P. Fisher, K. Flood, R. Foglio, M. Fohey, S. Fopp, N. Fouque, Y. Galaktionov, M. Gallilee, L. Gallin-Martel, G. Gallucci, B. Garcia, J. Garcia, R. Garcia-Lopez, L. Garcia-Tabares, C. Gargiulo, H. Gast, I. Gebauer, S. Gentile, M. Gervasi, W. Gillard, F. Giovacchini, L. Girard, P. Goglov, J. Gong, C. Goy-Henningsen, D. Grandi, M. Graziani, A. Grechko, A. Gross, I. Guerri, C. De La Guia, K.H. Guo, M. Habiby, S. Haino, F. Hauler, Z.H. He, M. Heil, J. Heilig, R. Hermel, H. Hofer, Z.C. Huang, W. Hungerford, M. Incagli, M. Ionica, A. Jacholkowska, W.Y. Jang, H. Jinchi, M. Jongmanns, L. Journet, L. Jungermann, W. Karpinski, G.N. Kim, K.S. Kim, T. Kirn, R. Kossakowski, A. Koulemzine, O. Kounina, A. Kounine, V. Koutsenko, M.S. Krafczyk, E. Laudi, G. Laurenti, C. Lauritzen, A. Lebedev, M.W. Lee, S.C. Lee, C. Leluc, H. Leon Vargas, V. Lepareur, J.Q. Li, Q. Li, T.X. Li, W. Li, Z.H. Li, P. Lipari, C.H. Lin, D. Liu, H. Liu, T. Lomtadze, Y.S. Lu, S. Lucidi, K. Lubelsmeyer, J.Z. Luo, W. Lustermann, S. Lv, J. Madsen, R. Majka, A. Malinin, C. Mana, J. Marin, T. Martin, G. Martinez, F. Masciocchi, N. Masi, D. Maurin, A. Mcinturff, P. Mcintyre, A. Menchaca-Rocha, Q. Meng, M. Menichelli, I. Mereu, M. Millinger, D.C. Mo, M. Molina, P. Mott, A. Mujunen, S. Natale, P. Nemeth, J.Q. Ni, N. Nikonov, F. Nozzoli, P. Nunes, A. Obermeier, S. Oh, A. Oliva, F. Palmonari, C. Palomares, M. Paniccia, A. Papi, W.H. Park, M. Pauluzzi, F. Pauss, A. Pauw, E. Pedreschi, S. Pensotti, R. Pereira, E. Perrin, G. Pessina, G. Pierschel, F. Pilo, A. Piluso, C. Pizzolotto, V. Plyaskin, J. Pochon, M. Pohl, V. Poireau, S. Porter, J. Pouxe, A. Putze, L. Quadrani, X.N. Qi, P.G. Rancoita, D. Rapin, Z.L. Ren, J.S. Ricol, E. Riihonen, I. Rodriguez, U. Roeser, S. Rosier-Lees, L. Rossi, A. Rozhkov, D. Rozza, A. Sabellek, R. Sagdeev, J. Sandweiss, B. Santos, P. Saouter, M. Sarchioni, S. Schael, D. Schinzel, M. Schmanau, G. Schwering, A. Schulz Von Dratzig, G. Scolieri, E.S. Seo, B.S. Shan, J.Y. Shi, Y.M. Shi, T. Siedenburg, R. Siedling, D. Son, F. Spada, F. Spinella, M. Steuer, K. Stiff, W. Sun, W.H. Sun, X.H. Sun, M. Tacconi, C.P. Tang, X.W. Tang, Z.C. Tang, L. Tao, J. Tassan-Viol, S.C.C. Ting, S.M. Ting, C. Titus, N. Tomassetti, F. Toral, J. Torsti, J.R. Tsai, J.C. Tutt, J. Ulbricht, T. Urban, V. Vagelli, E. Valente, C. Vannini, E. Valtonen, M. Vargas Trevino, S. Vaurynovich, M. Vecchi, M. Vergain, B. Verlaat, C. Vescovi, J.P. Vialle, G. Viertel, G. Volpini, D. Wang, N.H. Wang, Q.L. Wang, R.S. Wang, X. Wang, Z.X. Wang, W. Wallraff, Z.L. Weng, M. Willenbrock, M. Wlochal, H. Wu, K.Y. Wu, Z.S. Wu, W.J. Xiao, S. Xie, R.Q. Xiong, G.M. Xin, N.S. Xu, W. Xu, Q. Yan, J. Yang, M. Yang, Q.H. Ye, H. Yi, Y.J. Yu, Z.Q. Yu, S. Zeissler, J.G. Zhang, Z. Zhang, M.M. Zhang, Z.M. Zheng, H.L. Zhuang, V. Zhukov, A. Zichichi, P. Zuccon, C. Zurbach. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 110:14(2013), pp. 141102.1-141102.10.

First result from the alpha magnetic spectrometer on the international space station: Precision measurement of the positron fraction in primary cosmic rays of 0.5-350 gev

L. Rossi;G. Volpini;
2013

Abstract

A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8×106 positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼250 GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.
Time-of-flight; fast trigger; AMS-02 TRD; prototype; detector
Settore FIS/01 - Fisica Sperimentale
2013
Article (author)
File in questo prodotto:
File Dimensione Formato  
PhysRevLett.110.141102-accepted.pdf

accesso aperto

Tipologia: Post-print, accepted manuscript ecc. (versione accettata dall'editore)
Dimensione 409.18 kB
Formato Adobe PDF
409.18 kB Adobe PDF Visualizza/Apri
PhysRevLett.110.141102.pdf

accesso aperto

Tipologia: Publisher's version/PDF
Dimensione 610.67 kB
Formato Adobe PDF
610.67 kB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/665305
Citazioni
  • ???jsp.display-item.citation.pmc??? 12
  • Scopus 1020
  • ???jsp.display-item.citation.isi??? 841
social impact