Examination of uncertainties in nuclear data for cosmic ray physics with the AMS experiment

TL;DR

This paper evaluates how nuclear data uncertainties affect the interpretation of cosmic ray measurements from AMS, highlighting that these uncertainties limit the ability to precisely determine cosmic ray propagation parameters.

Contribution

It provides the first detailed assessment of nuclear uncertainties in Be and B production and their impact on constraining cosmic ray propagation models using AMS data.

Findings

Nuclear uncertainties significantly limit parameter constraints.

AMS data can potentially break degeneracies if uncertainties are reduced.

High-energy Be/B measurements are more valuable for nuclear physics tests.

Abstract

High-energy Li-Be-B nuclei in cosmic rays are being measured with unprecedent accuracy by the AMS experiment. These data bring valuable information to the cosmic ray propagation physics. In particular, combined measurements of B/C and Be/B ratios may allow to break the parameter degeneracy between the cosmic-ray diffusion coefficient and the size of the propagation region, which is crucial for dark matter searches. The parameter determination relies in the calculation of the Be and B production from collisions of heavier nuclei with the gas. Using the available cross-section data, I present for the first time an evaluation of the nuclear uncertainties and their impact in constraining the propagation models. I found that the AMS experiment can provide tight constraints on the transport parameters allowing to resolutely break the degeneracy, while nuclear uncertainties in the models are found to be a major limiting factor. Once these uncertainties are accounted, the degeneracy remains poorly resolved. In particular, the Be/B ratio at ~1 - 10 GeV/n is found not to bring valuable information for the parameter extraction. On the other hand, precise Be/B data at higher energy may be useful to test the nuclear physics inputs of the models.