a,b* on behalf of the ISS-CREAM Collaboration

Significant spectral hardening at around 200 GV magnetic rigidity has been reported by AMS-02, ATIC-2, CALET, CREAM, DAMPE, and PAMELA. This has been observed in high-accuracy measurements of various nuclei energy spectra of both primaries and secondaries. To explain the spectral hardening while maintaining proper B/C and p/He ratios, we study 3 approaches in a reacceleration model: adding a diffusion coefficient break, introducing extra source injection breaks, and a combination of both. We use the numerical code GALPROP to compute the propagation of cosmic rays with such parameter sets on the rigidity dependence of source and propagation parameters. Implications on the positron spectra are discussed.

No abstract

Structure analysis of 159 Sm and properties of odd-mass neutron-rich nuclei in mass-160 region SCIENCE CHINA Physics, Mechanics & Astronomy 54, 81 (2011); Shell-model structure of exotic nuclei beyond 132 Sn European Physical Journal ST(Special Topics) 150, 93 (2007); β-decay studies of the neutron-rich 18,21 N isotopes SCIENCE CHINA Physics, Mechanics & Astronomy 54, 53 (2011); β-decay study of neutron-rich nucleus 34 Al

The high-accuracy measurements of protons and nuclei energy spectra in the cosmic ray experiment AMS confirmed the earlier experimental results of ATIC-2, CREAM and PAMELA measurements on the presence of spectral hardening at magnetic rigidity about 200 GV. The AMS data on the secondary nuclei Li, Be and B indicated that the hardening could be due to the transition to weaker rigidity dependence of cosmic ray confinement time in the Galaxy above 200 GV. However, the possible hardening of the source spectrum is also not excluded. To study the origin of spectrum hardening, we use the numerical code GALPROP to compute the propagation of cosmic rays under different assumptions on the rigidity dependence of cosmic ray source and propagation parameters in a few Galactic models.