Letter

Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons

Received:
Accepted:
Published online:

Abstract

High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes1,2,3,4,5,6,7 and may enable the observation of phenomena such as dark-matter particle annihilation or decay8,9,10. The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon- or space-borne experiments11,12,13,14,15,16, and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov γ-ray telescope arrays17,18. Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements17,18, although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range 25 gigaelectronvolts to 4.6 teraelectronvolts by the Dark Matter Particle Explorer (DAMPE)19 with unprecedentedly high energy resolution and low background. The largest part of the spectrum can be well fitted by a ‘smoothly broken power-law’ model rather than a single power-law model. The direct detection of a spectral break at about 0.9 teraelectronvolts confirms the evidence found by previous indirect measurements17,18, clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.

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Acknowledgements

The DAMPE mission is funded by the strategic priority science and technology projects in space science of the Chinese Academy of Sciences. In China the data analysis was supported in part by the National Key R&D Program of China (number 2016YFA0400200), the National Basic Research Program of China (number 2013CB837000), the National Natural Science Foundation of China (numbers 11525313, 11622327 and U1738206) and the 100 Talents Program of Chinese Academy of Sciences. In Europe the activities and the data analysis are supported by the Swiss National Science Foundation (SNSF), Switzerland; the National Institute for Nuclear Physics (INFN), Italy.

Author information

Author notes

    • DAMPE Collaboration

    dampe@pmo.ac.cn

Affiliations

  1. Istituto Nazionale di Fisica Nucleare (INFN)—Sezione di Perugia, I-06123 Perugia, Italy.

    • G. Ambrosi
    • , B. Bertucci
    • , M. Duranti
    • , D. D’Urso
    • , S. Garrappa
    • , M. Ionica
    •  & V. Vagelli
  2. State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei 230026, China.

    • Q. An
    • , H. F. Chen
    • , J. N. Dong
    • , C. Q. Feng
    • , F. J. Gan
    • , S. S. Gao
    • , G. S. Huang
    • , D. Jiang
    • , X. Jin
    • , S. B. Liu
    • , S. Y. Ma
    • , Z. T. Shen
    • , C. Wang
    • , Q. Wang
    • , X. L. Wang
    • , Y. F. Wang
    • , Y. F. Wei
    • , L. B. Wu
    • , Z. Z. Xu
    • , D. L. Zhang
    • , J. B. Zhang
    • , Y. L. Zhang
    • , Z. Y. Zhang
    •  & X. Zhu
  3. Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China.

    • Q. An
    • , H. F. Chen
    • , J. N. Dong
    • , C. Q. Feng
    • , F. J. Gan
    • , S. S. Gao
    • , G. S. Huang
    • , D. Jiang
    • , X. Jin
    • , S. B. Liu
    • , S. Y. Ma
    • , Z. T. Shen
    • , C. Wang
    • , Q. Wang
    • , X. L. Wang
    • , Y. F. Wang
    • , Y. F. Wei
    • , L. B. Wu
    • , Z. Z. Xu
    • , D. L. Zhang
    • , J. B. Zhang
    • , Y. L. Zhang
    • , Z. Y. Zhang
    •  & X. Zhu
  4. Department of Nuclear and Particle Physics, University of Geneva, CH-1211 Geneva, Switzerland.

    • R. Asfandiyarov
    • , P. Azzarello
    • , D. Droz
    • , V. Gallo
    • , M. M. Salinas
    • , A. Tykhonov
    • , S. Vitillo
    • , X. Wu
    •  & S. Zimmer
  5. Dipartimento di Matematica e Fisica E. De Giorgi, Università del Salento, I-73100 Lecce, Italy.

    • P. Bernardini
    • , A. D’Amone
    • , A. De Benedittis
    • , I. De Mitri
    •  & G. Marsella
  6. Istituto Nazionale di Fisica Nucleare (INFN)—Sezione di Lecce, I-73100 Lecce, Italy.

    • P. Bernardini
    • , A. D’Amone
    • , A. De Benedittis
    • , I. De Mitri
    • , M. Di Santo
    • , G. Marsella
    •  & A. Surdo
  7. Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, I-06123 Perugia, Italy.

    • B. Bertucci
    • , M. Duranti
    • , S. Garrappa
    •  & V. Vagelli
  8. Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China.

    • M. S. Cai
    • , J. Chang
    • , D. Y. Chen
    • , W. Chen
    • , M. Y. Cui
    • , T. K. Dong
    • , K. K. Duan
    • , Y. Z. Fan
    • , L. Feng
    • , Y. Z. Gong
    • , J. H. Guo
    • , Y. M. Hu
    • , Y. Y. Huang
    • , W. Jiang
    • , S. J. Lei
    • , S. Li
    • , X. Li
    • , Y. F. Liang
    • , N. H. Liao
    • , H. Liu
    • , Y. Liu
    • , P. X. Ma
    • , T. Ma
    • , X. Y. Peng
    • , Z. Q. Shen
    • , M. Su
    • , S. Wang
    • , Y. P. Wang
    • , Y. Z. Wang
    • , S. C. Wen
    • , D. M. Wei
    • , J. J. Wei
    • , J. Wu
    • , Z. Q. Xia
    • , Y. L. Xin
    • , Z. L. Xu
    • , Q. Yuan
    • , C. Yue
    • , J. J. Zang
    • , C. Zhang
    • , L. Zhang
    • , P. F. Zhang
    • , Y. Zhang
    • , Y. Q. Zhang
    •  & Z. Zhang
  9. School of Astronomy and Space Science, University of Science and Technology of China, Hefei 230026, China.

    • M. S. Cai
    • , J. Chang
    • , Y. Z. Fan
    • , W. Jiang
    • , P. X. Ma
    • , D. M. Wei
    • , J. Wu
    • , Z. Q. Xia
    •  & Q. Yuan
  10. University of Chinese Academy of Sciences, Yuquan Road 19, Beijing 100049, China.

    • D. Y. Chen
    • , W. Chen
    • , K. K. Duan
    • , S. Li
    • , Y. F. Liang
    • , Z. Q. Shen
    • , S. Wang
    • , Y. P. Wang
    • , Y. Z. Wang
    • , S. C. Wen
    • , Z. L. Xu
    • , C. Yue
    • , L. Zhang
    • , Y. Zhang
    •  & Y. Q. Zhang
  11. Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000, China.

    • J. L. Chen
    • , J. L. Duan
    • , F. Fang
    • , J. Kong
    • , Y. Li
    • , J. Liu
    • , W. Q. Liu
    • , D. Mo
    • , X. Y. Niu
    • , H. Su
    • , Z. Y. Sun
    • , X. H. Wang
    • , Z. M. Wang
    • , K. Xi
    • , H. B. Yang
    • , P. Yang
    • , Y. Q. Yang
    • , Z. L. Yang
    • , H. J. Yao
    • , Y. H. Yu
    • , J. Z. Zhang
    • , S. X. Zhang
    • , Y. J. Zhang
    • , Y. P. Zhang
    • , H. Y. Zhao
    •  & Y. Zhou
  12. National Space Science Center, Chinese Academy of Sciences, Nanertiao 1, Zhongguancun, Haidian district, Beijing 100190, China.

    • T. S. Cui
    • , Z. X. Dong
    • , W. L. Li
    • , Y. M. Liang
    • , M. Ma
    • , X. Q. Ma
    • , X. Y. Ma
    • , J. N. Rao
    • , G. Z. Shang
    • , W. H. Shen
    • , J. X. Song
    • , X. J. Teng
    • , X. B. Tian
    • , H. Wang
    • , L. G. Wang
    • , S. S. Wu
    • , H. T. Xu
    • , G. F. Xue
    • , W. Z. Zhang
    • , X. F. Zhao
    • , C. Y. Zhou
    •  & Y. Zhu
  13. Institute of High Energy Physics, Chinese Academy of Sciences, YuquanLu 19B, Beijing 100049, China.

    • Y. F. Dong
    • , R. R. Fan
    • , M. Gao
    • , K. Gong
    • , D. Y. Guo
    • , W. X. Peng
    • , R. Qiao
    • , H. Y. Wang
    • , J. Z. Wang
    • , D. Wu
    • , F. Zhang
    • , J. Y. Zhang
    •  & H. Zhao
  14. Istituto Nazionale di Fisica Nucleare (INFN)—Sezione di Bari, I-70125 Bari, Italy.

    • G. Donvito
    • , P. Fusco
    • , F. Gargano
    • , F. Loparco
    •  & M. N. Mazziotta
  15. ASI Space Science Data Center (SSDC), I-00133 Roma, Italy.

    • D. D’Urso
  16. Dipartimento di Fisica ‘M. Merlin’ dell’Univerisità e del Politecnico di Bari, I-70126 Bari, Italy.

    • P. Fusco
    •  & F. Loparco
  17. Department of Physics and Laboratory for Space Research, University of Hong Kong, Pok Fu Lam, Hong Kong, China.

    • M. Su

Consortia

  1. DAMPE Collaboration

Authors

    Contributions

    This work is the result of the contributions and efforts of all the participating institutes, under the leadership of Purple Mountain Observatory, the Chinese Academy of Sciences. All authors have reviewed, discussed, and commented on the present results and on the manuscript. In line with collaboration policy, the authors are listed alphabetically.

    Competing interests

    The author declare no competing financial interests.

    Reviewer Information Nature thanks D. Hooper and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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