Measurement of the cosmic p+He energy spectrum from 50 GeV to 0.5 PeV with the DAMPE space mission

Alemanno, F.; Altomare, C.; An, Q.; Azzarello, P.; Barbato, F. C. T.; Bernardini, P.; X. J., Bi; Cagnoli, I.; Cai, M. S.; Casilli, E.; Catanzani, E.; Chang, J.; Chen, D. Y.; Chen, J. L.; Chen, Z. F.; Coppin, P.; Cui, M. Y.; Cui, T. S.; Cui, Y. X.; Dai, H. T.; De Benedittis, A.; De Mitri, I.; De Palma, F.; Deliyergiyev, M.; Di Giovanni, A.; Di Santo, M.; Ding, Q.; Dong, T. K.; Dong, Z. X.; Donvito, G.; Droz, D.; Duan, J. L.; Duan, K. K.; Fan, R. R.; Fan, Y. Z.; Fang, F.; Fang, K.; Feng, C. Q.; Feng, L.; Alonso, M. F.; Frieden, J. M.; Fusco, P.; Gao, M.; Gargano, F.; Gong, K.; Gong, Y. Z.; Guo, D. Y.; Guo, J. H.; Han, S. X.; Y. M., Hu; Huang, G. S.; Huang, X. Y.; Huang, Y. Y.; Ionica, M.; Jiang, L. Y.; Jiang, Y. Z.; Jiang, W.; Kong, J.; Kotenko, A.; Kyratzis, D.; Lei, S. J.; W. H., Li; W. L., Li; Li, X.; X. Q., Li; Liang, Y. M.; Liu, C. M.; Liu, H.; Liu, J.; Liu, S. B.; Liu, Y.; Loparco, F.; Luo, C. N.; Ma, M.; P. X., Ma; Ma, T.; X. Y., Ma; Marsella, G.; Mazziotta, M. N.; Mo, D.; Salinas, M. M.; Niu, X. Y.; Pan, X.; Parenti, A.; Peng, W. X.; Peng, X. Y.; Perrina, C.; Putti-Garcia, E.; Qiao, R.; Rao, J. N.; Ruina, A.; Shangguan, Z.; Shen, W. H.; Shen, Z. Q.; Shen, Z. T.; Silveri, L.; Song, J. X.; Stolpovskiy, M.; Su, H.; Su, M.; Sun, H. R.; Sun, Z. Y.; Surdo, A.; Teng, X. J.; Tykhonov, A.; Wang, J. Z.; Wang, L. G.; Wang, S.; Wang, S. X.; Wang, X. L.; Wang, Y.; Wang, Y. F.; Wang, Y. Z.; Wang, Z. M.; Wei, D. M.; Wei, J. J.; Wei, Y. F.; Wu, D.; Wu, J.; L. B., Wu; S. S., Wu; Wu, X.; Xia, Z. Q.; H. T., Xu; Xu, J.; Z. H., Xu; Z. L., Xu; E. H., Xu; Z. Z., Xu; Xue, G. F.; Yang, H. B.; Yang, P.; Yang, Y. Q.; Yao, H. J.; Y. H., Yu; Yuan, G. W.; Yuan, Q.; Yue, C.; Zang, J. J.; Zhang, S. X.; Zhang, W. Z.; Zhang, Y.; Zhang, Y.; Zhang, Y. J.; Zhang, Y. L.; Zhang, Y. P.; Zhang, Y. Q.; Zhang, Z.; Zhang, Z. Y.; Zhao, C.; Zhao, H. Y.; Zhao, X. F.; Zhou, C. Y.; Zhu, Y.

doi:10.1103/PhysRevD.109.L121101

Recent observations of the light component of the cosmic-ray spectrum have revealed unexpected features that motivate further and more precise measurements up to the highest energies. The Dark Matter Particle Explorer is a satellite-based cosmic-ray experiment that has been operational since December 2015, continuously collecting data on high-energy cosmic particles with very good statistics, energy resolution, and particle identification capabilities. In this work, the latest measurements of the energy spectrum of proton+helium in the energy range from 46 GeV to 464 TeV are presented. Among the most distinctive features of the spectrum, a spectral hardening at 600 GeV has been observed, along with a softening at 29 TeV measured with a 6.6σ significance. Moreover, the detector features and the analysis approach allowed for the extension of the spectral measurement up to the sub-PeV region. Even if with small statistical significance due to the low number of events, data suggest a new spectral hardening at about 150 TeV.