Testing the consistency of proapgation between light and heavy cosmic ray nuclei

Abstract

One of the fundamental issues in cosmic ray physics is to explain the nature of cosmic ray acceleration and propagation mechanisms. Thanks to the precise cosmic ray data measured by recent space experiments, we are able to investigate the cosmic ray acceleration and propagation models more comprehensively and reliably. In this paper, we combine the secondary-to-primary ratios and the primary spectra measured by PAMELA, AMS02, ACE-CRIS and Voyager-1 to constrain the cosmic ray source and transport parameters. The study shows that the Z > 2 data yield a high-energy diffusion slope δ2 ∼ (0.37, 0.44). The Z ≤ 2 species obtain a looser constraint on δ2 ∼ (0.34, 0.44). The overlap infers the heavy and light particles can give compatible results at high energies. Meanwhile, at low energies, significant disagreements exist between the heavy and light elements. The B/C ratio requires a much larger diffusion slope variation δ2-δ1 around 4 GV or a stronger Alfvén velocity vA than the low-mass data. This indicates that the heavy and light particles may suffer different low-energy transport behaviors in Galaxy. However, better understanding on the consistency/inconsistency between the heavy and light relies on more precise cross-sections, better constraints on correlations in systematic errors of data, and more accurate description for Solar modulation during the reversal period of HMF.

A simple determination of the halo size from10Be/9Be data

“…In this study we consider four different production cross-section sets, including the Galp-opt12 set from the galprop team, because it has been the most used set in recent CR analyses (Génolini et al 2019;Weinrich et al 2020b;Boschini et al 2020a,b;Korsmeier & Cuoco 2021;Wang et al 2021); it is also the set used in our previous effort to determine L from AMS-02 Be/B data (Weinrich et al 2020a). We also consider the OPT12, OPT12up22, and OPT22 sets, discussed in detail in Maurin et al (2022), with the most-plausible set being OPT12up22.…”

A simple determination of the halo size $L$ from $^{10}$Be/$^9$Be data

“…We consider in this study four different production cross-section sets, including the Galp-opt12 set from the galprop team, because it has been the most-used set in recent GCR analyses (Génolini et al 2019;Weinrich et al 2020b;Boschini et al 2020a,b;Korsmeier & Cuoco 2021;Wang et al 2021); it is also the set used in our previous effort to determine L from AMS-02 Be/B data (Weinrich et al 2020a). We also consider the OPT12, OPT12up22, and OPT22 sets discussed in detail in Maurin et al (2022), with the most-plausible set being OPT12up22.…”