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

	Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons
	G. Ambrosi; Q. An; R. Asfandiyarov; P. Azzarello; P. Bernardini; B. Bertucci; M. S. Cai; J. Chang; D. Y. Chen; H. F. Chen
刊名	Nature
	2017
关键词	Particle Dark-matter Supernova-remnants Dampe Propagation Candidates Signature Energies Galaxy
ISSN号	0028-0836
英文摘要	High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes(1-7) and may enable the observation of phenomena such as dark-matter particle annihilation or decay(8-10). The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon-or space-borne experiments(11-16), and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov gamma-ray telescope arrays(17,18). Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements(17,18), 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 measurements(17,18), clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.
语种	英语
内容类型	期刊论文
源URL	[http://ir.nssc.ac.cn/handle/122/6041]
专题	国家空间科学中心_空间技术部
推荐引用方式 GB/T 7714	G. Ambrosi,Q. An,R. Asfandiyarov,et al. Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons[J]. Nature,2017.
APA	G. Ambrosi.,Q. An.,R. Asfandiyarov.,P. Azzarello.,P. Bernardini.,...&Y. Zhu & S. Zimmer.(2017).Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons.Nature.
MLA	G. Ambrosi,et al."Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons".Nature (2017).