Measurement of Fragmentation Cross Sections of Intermediate-Mass Nuclei with NA61/SHINE at CERN

Cosmic-ray propagation in the galaxy can be constrained by modeling the secondary-to-primary cosmic-ray flux ratios, like the boron-to-carbon flux ratio that reaches Earth. While these fluxes are currently measured with higher precision(<5%) by space-based detectors like AMS, CALET, and DAMPE, insufficient knowledge of nuclear fragmentation cross sections hinders our inference of propagation parameters. Therefore, laboratory measurements of fragmentation cross section above 10 A GeV/c are essential. We remediate this situation by utilizing the NA61/SHINE experimental facility at CERN.
Pilot data on fragmentation was taken in 2018 with the main aim of probing the feasibility of performing fragmentation studies at SPS energies. Two fixed targets, polyethylene(C2H4) and graphite were employed to study C+p interactions at 13.5 A GeV/c beam momentum. In this contribution, we will present the isotopic production of boron including direct production of 10B & 11B as well as via indirect channels originating from the decay of 10C and 11C fragments. We also report on the feasibility of measuring light and intermediate-mass nuclei from Li to F relevant for cosmic ray propagation studies. ... mehrA dedicated high statistics data-taking is scheduled in late 2023 to study the fragmentation of various primary nuclei like C, N, O & Si.