THE B/C and SUB-IRON/IRON COSMIC RAY RATIOS - FURTHER EVIDENCE in FAVOR of the SPIRAL-ARM DIFFUSION MODEL

David Benyamin, Ehud Nakar, Tsvi Piran, Nir J. Shaviv

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

The boron to carbon (B/C) and sub-Fe/Fe ratios provide an important clue on cosmic ray (CR) propagation within the Galaxy. These ratios estimate the grammage that the CRs traverse as they propagate from their sources to Earth. Attempts to explain these ratios within the standard CR propagation models require ad hoc modifications and even with those these models necessitate inconsistent grammages to explain both ratios. As an alternative, physically motivated model, we have proposed that CRs originate preferably within the galactic spiral arms. CR propagation from dynamic spiral arms has important imprints on various secondary to primary ratios, such as the B/C ratio and the positron fraction. We use our spiral-arm diffusion model with the spallation network extended up to nickel to calculate the sub-Fe/Fe ratio. We show that without any additional parameters the spiral-arm model consistently explains both ratios with the same grammage, providing further evidence in favor of this model.

Original languageAmerican English
Article number47
JournalAstrophysical Journal
Volume826
Issue number1
DOIs
StatePublished - 20 Jul 2016

Bibliographical note

Publisher Copyright:
© 2016. The American Astronomical Society. All rights reserved..

Keywords

  • Galaxy: kinematics and dynamics
  • cosmic rays
  • diffusion

Fingerprint

Dive into the research topics of 'THE B/C and SUB-IRON/IRON COSMIC RAY RATIOS - FURTHER EVIDENCE in FAVOR of the SPIRAL-ARM DIFFUSION MODEL'. Together they form a unique fingerprint.

Cite this