Observations of the Li, Be, and B isotopes and constraints on cosmic-ray propagation

G. A. de Nolfo; I. V. Moskalenko; W. R. Binns; E. R. Christian; A. C. Cummings; A. J. Davis; J. S. George; P. L. Hink; M. H. Israel; R. A. Leske; M. Lijowski; R. A. Mewaldt; E. C. Stone; A. W. Strong; T. T. von Rosenvinge; M. E. Wiedenbeck; N. E. Yanasak

doi:10.1016/j.asr.2006.09.008

arXiv · astro-ph/0611301

Observations of the Li, Be, and B isotopes and constraints on cosmic-ray propagation

G. A. de Nolfo·I. V. Moskalenko·W. R. Binns·E. R. Christian·A. C. Cummings·A. J. Davis·J. S. George·P. L. Hink·M. H. Israel·R. A. Leske·M. Lijowski·R. A. Mewaldt·E. C. Stone·A. W. Strong·T. T. von Rosenvinge·M. E. Wiedenbeck·N. E. Yanasak

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Abstract

The abundance of Li, Be, and B isotopes in galactic cosmic rays (GCR) between E=50-200 MeV/nucleon has been observed by the Cosmic Ray Isotope Spectrometer (CRIS) on NASA's ACE mission since 1997 with high statistical accuracy. Precise observations of Li, Be, B can be used to constrain GCR propagation models. \iffalse Precise observations of Li, Be, and B in addition to well-measured production cross-sections are used to further constrain GCR propagation models. \fi We find that a diffusive reacceleration model with parameters that best match CRIS results (e.g. B/C, Li/C, etc) are also consistent with other GCR observations. A $\sim$15--20% overproduction of Li and Be in the model predictions is attributed to uncertainties in the production cross-section data. The latter becomes a significant limitation to the study of rare GCR species that are generated predominantly via spallation.

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G. A. de Nolfo, I. V. Moskalenko, W. R. Binns, E. R. Christian, A. C. Cummings, A. J. Davis, J. S. George, P. L. Hink, M. H. Israel, R. A. Leske, M. Lijowski, R. A. Mewaldt, E. C. Stone, A. W. Strong, T. T. von Rosenvinge, M. E. Wiedenbeck, N. E. Yanasak. 2006-11-09. Observations of the Li, Be, and B isotopes and constraints on cosmic-ray propagation. https://doi.org/10.1016/j.asr.2006.09.008

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