English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The AMS-02 experiment has reported a new measurement of the antiproton/protonratio in Galactic cosmic rays (CRs). In the energy range $E\sim\,$60-450 GeV,this ratio is found to be remarkably constant. Using recent data on CR proton,helium, and carbon fluxes, 10Be/9Be and B/C ratios, we have performed a globalBayesian analysis based on a Markov-Chain Monte-Carlo sampling algorithm undera "two halo model" of CR propagation. In this model, CRs are allowed toexperience a different type of diffusion when they propagate in the regionclose of the Galactic disk. We found that the vertical extent of this region isabout 900 pc above and below the disk, and the corresponding diffusioncoefficient scales with energy as $D\sim\,E^{0.15}$, describing well theobservations on primary CR spectra, secondary/primary ratios and anisotropy.Under this model we have carried out improved calculations of antiparticlespectra arising from secondary CR production and their correspondinguncertainties. We made use of Monte-Carlo generators and accelerator data toassess the antiproton production cross-sections and their uncertainties. Whilethe positron excess requires the contribution of additional unknown sources, wefound that the new AMS-02 antiproton data are consistent, within the estimateduncertainties, with our calculations based on secondary production.

Bayesian analysis of spatial-dependent cosmic-ray propagation: astrophysical background of antiprotons and positrons