Precision measurement of boron to carbon flux ratio in cosmic rays from 2 GV to 1.8 TV with the alpha magnetic spectrometer on the international space station

Abstract

AMS-02 is wide acceptance high-energy physics experiment installed on the International Space Station in May 2011 and operating continuously since then. AMS-02 is able to precisely separate cosmic rays light nuclei (1 - Z - 8) with contaminations less than 10-3. The light nuclei cosmic ray Boron to Carbon flux ratio is very well known sensitive observable for the understanding of the propagation of cosmic rays in the Galaxy, being Boron a secondary product of spallation on the interstellar medium of heavier primary elements such as Carbon and Oxygen. A precision measurement based on 10 million events of the Boron to Carbon ratio in the rigidity range from 2 GV to 1.8 TV is presented.