Format

Send to

Choose Destination
Phys Rev Lett. 2019 Feb 1;122(4):041102. doi: 10.1103/PhysRevLett.122.041102.

Towards Understanding the Origin of Cosmic-Ray Positrons.

Aguilar M1, Ali Cavasonza L2, Ambrosi G3, Arruda L4, Attig N5, Azzarello P6, Bachlechner A2, Barao F4, Barrau A7, Barrin L8, Bartoloni A9, Basara L10, Başeğmez-du Pree S11, Battiston R10,12, Becker U13, Behlmann M13, Beischer B2, Berdugo J1, Bertucci B3,14, Bindi V15, de Boer W16, Bollweg K17, Borgia B9,18, Boschini MJ19, Bourquin M6, Bueno EF20, Burger J13, Burger WJ10, Cai XD13, Capell M13, Caroff S21, Casaus J1, Castellini G22, Cervelli F23, Chang YH24, Chen GM25, Chen HS25,26, Chen Y6, Cheng L27, Chou HY24, Choutko V13, Chung CH2, Clark C17, Coignet G21, Consolandi C15, Contin A28,29, Corti C15, Crispoltoni M3,14, Cui Z27, Dadzie K13, Dai YM30, Datta A15, Delgado C1, Della Torre S19, Demirköz MB31, Derome L7, Di Falco S23, Dimiccoli F8,10, Díaz C1, von Doetinchem P15, Dong F32, Donnini F3, Duranti M3, Egorov A13, Eline A13, Eronen T33, Feng J13, Fiandrini E3,14, Fisher P13, Formato V3, Galaktionov Y13, García-López RJ34, Gargiulo C8, Gast H2, Gebauer I16, Gervasi M19,35, Giovacchini F1, Gómez-Coral DM36, Gong J32, Goy C21, Grabski V36, Grandi D19,35, Graziani M16, Guo KH37, Haino S38, Han KC39, He ZH37, Heil M13, Hsieh TH13, Huang H38, Huang ZC37, Incagli M23, Jia Y13, Jinchi H39, Kanishev K10, Khiali B3, Kirn T2, Konak C31, Kounina O13, Kounine A13, Koutsenko V13, Kulemzin A13, La Vacca G19,35, Laudi E8, Laurenti G28, Lazzizzera I10,12, Lebedev A13, Lee HT40, Lee SC38, Leluc C6, Li JQ32, Li Q32, Li TX37, Li ZH25, Light C15, Lin CH38, Lippert T5, Liu FZ13, Liu H13,24, Liu Z6, Lu SQ38, Lu YS25, Luebelsmeyer K2, Luo F27, Luo JZ32, Luo X15, Lyu SS37, Machate F2, Mañá C1, Marín J1, Martin T17, Martínez G1, Masi N28, Maurin D7, Menchaca-Rocha A36, Meng Q32, Mo DC37, Molero M1, Mott P17, Mussolin L3,14, Nelson T15, Ni JQ37, Nikonov N2, Nozzoli F10, Oliva A1, Orcinha M4, Palermo M15, Palmonari F28,29, Paniccia M6, Pashnin A13, Pauluzzi M3,14, Pensotti S19,35, Perrina C6, Phan HD13, Picot-Clemente N41, Plyaskin V13, Pohl M6, Poireau V21, Popkow A15, Quadrani L28,29, Qi XM37, Qin X13, Qu ZY38, Rancoita PG19, Rapin D6, Conde AR34, Rosier-Lees S21, Rozhkov A13, Rozza D19,35, Sagdeev R42, Solano C13, Schael S2, Schmidt SM5, Schulz von Dratzig A2, Schwering G2, Seo ES41, Shan BS43, Shi JY32, Siedenburg T2, Song JW27, Sun ZT25, Tacconi M19,35, Tang XW25, Tang ZC25, Tian J3,14, Ting SCC13,8, Ting SM13, Tomassetti N3,14, Torsti J33, Urban T17, Vagelli V3,14, Valente E9,18, Valtonen E33, Vázquez Acosta M34, Vecchi M11,20, Velasco M1, Vialle JP21, Vizán J1, Wang LQ27, Wang NH27, Wang QL30, Wang X13, Wang XQ25,26, Wang ZX37, Wei J6, Weng ZL13, Wu H32, Xiong RQ32, Xu W13, Yan Q13, Yang Y44, Yi H32, Yu YJ30, Yu ZQ25, Zannoni M19,35, Zeissler S16, Zhang C25, Zhang F25, Zhang JH32, Zhang Z13, Zhao F25,26, Zheng ZM43, Zhuang HL25, Zhukov V2, Zichichi A28,29, Zimmermann N2, Zuccon P10,12; AMS Collaboration.

Author information

1
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), E-28040 Madrid, Spain.
2
I. Physics Institute and JARA-FAME, RWTH Aachen University, D-52056 Aachen, Germany.
3
INFN Sezione di Perugia, I-06100 Perugia, Italy.
4
Laboratório de Instrumentação e Física Experimental de Partículas (LIP), P-1000 Lisboa, Portugal.
5
Jülich Supercomputing Centre and JARA-FAME, Research Centre Jülich, D-52425 Jülich, Germany.
6
DPNC, Université de Genève, CH-1211 Genève 4, Switzerland.
7
Univ. Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, F-38000 Grenoble, France.
8
European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland.
9
INFN Sezione di Roma 1, I-00185 Roma, Italy.
10
INFN TIFPA, I-38123 Povo, Trento, Italy.
11
KVI-Center for Advanced Radiation Technology, University of Groningen, NL-9700 AB Groningen, the Netherlands.
12
Università di Trento, I-38123 Povo, Trento, Italy.
13
Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA.
14
Università di Perugia, I-06100 Perugia, Italy.
15
Physics and Astronomy Department, University of Hawaii, Honolulu, Hawaii 96822, USA.
16
Institut für Experimentelle Teilchenphysik, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe, Germany.
17
National Aeronautics and Space Administration Johnson Space Center (JSC), Jacobs Engineering, and Business Integra, Houston, Texas 77058, USA.
18
Università di Roma La Sapienza, I-00185 Roma, Italy.
19
INFN Sezione di Milano-Bicocca, I-20126 Milano, Italy.
20
Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos, São Paulo, SP, Brazil.
21
Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, LAPP-IN2P3, F-74000 Annecy, France.
22
CNR-IROE, I-50125 Firenze, Italy.
23
INFN Sezione di Pisa, I-56100 Pisa, Italy.
24
Physics Department and Center for High Energy and High Field, National Central University (NCU), Tao Yuan 32054, Taiwan.
25
Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing 100049, China.
26
University of Chinese Academy of Sciences (UCAS), Beijing 100049, China.
27
Shandong University (SDU), Jinan, Shandong 250100, China.
28
INFN Sezione di Bologna, I-40126 Bologna, Italy.
29
Università di Bologna, I-40126 Bologna, Italy.
30
Institute of Electrical Engineering (IEE), Chinese Academy of Sciences, Beijing 100190, China.
31
Department of Physics, Middle East Technical University (METU), 06800 Ankara, Turkey.
32
Southeast University (SEU), Nanjing 210096, China.
33
Space Research Laboratory, Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland.
34
Instituto de Astrofísica de Canarias (IAC), E-38205 La Laguna, and Departamento de Astrofísica, Universidad de La Laguna, E-38206 La Laguna, Tenerife, Spain.
35
Università di Milano-Bicocca, I-20126 Milano, Italy.
36
Instituto de Física, Universidad Nacional Autónoma de México (UNAM), México, D. F., 01000 Mexico.
37
Sun Yat-Sen University (SYSU), Guangzhou 510275, China.
38
Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
39
National Chung-Shan Institute of Science and Technology (NCSIST), Longtan, Tao Yuan 32546, Taiwan.
40
Academia Sinica Grid Center (ASGC), Nankang, Taipei 11529, Taiwan.
41
IPST, University of Maryland, College Park, Maryland 20742, USA.
42
East-West Center for Space Science, University of Maryland, College Park, Maryland 20742, USA.
43
Beihang University (BUAA), Beijing 100191, China.
44
National Cheng Kung University, Tainan 70101, Taiwan.

Abstract

Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are (a) a significant excess starting from 25.2±1.8  GeV compared to the lower-energy, power-law trend, (b) a sharp dropoff above 284_{-64}^{+91}  GeV, (c) in the entire energy range the positron flux is well described by the sum of a term associated with the positrons produced in the collision of cosmic rays, which dominates at low energies, and a new source term of positrons, which dominates at high energies, and (d) a finite energy cutoff of the source term of E_{s}=810_{-180}^{+310}  GeV is established with a significance of more than 4σ. These experimental data on cosmic ray positrons show that, at high energies, they predominantly originate either from dark matter annihilation or from other astrophysical sources.

Supplemental Content

Full text links

Icon for American Physical Society
Loading ...
Support Center