Hadronic cross section measurements with the DAMPE space mission using 20 GeV-10 TeV cosmic-ray protons and He 4

Alemanno, F.; 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.; Di Giovanni, A.; 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.; 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.; 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.; Sarkar, R.; Savina, P.; Serpolla, 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.; 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.111.012002

Precise direct cosmic-ray (CR) measurements provide an important probe to study the energetic particle sources in our Galaxy, and the interstellar environment through which these particles propagate. Uncertainties on hadronic models, ion-nucleon cross sections in particular, are currently the limiting factor toward obtaining more accurate CR ion flux measurements with calorimetric space-based experiments. We present an energy-dependent measurement of the inelastic cross section of protons and helium-4 nuclei (alpha particles) on a Bi4Ge3O12 target, using 88 months of data collected by the DAMPE space mission. The kinetic energy range per nucleon of the measurement points ranges from 18 GeV to 9 TeV for protons, and from 5 GeV/n to 3 TeV/n for helium-4 nuclei. Our results lead to a significant improvement of the CR flux normalization. In the case of helium-4, these results correspond to the first cross section measurements on a heavy target material at energies above 10 GeV/n.