Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10695267 | Advances in Space Research | 2005 | 6 Pages |
Abstract
Recent measurements of the cosmic ray (CR) antiproton flux have been shown to challenge existing CR propagation models. It was shown that the reacceleration models designed to match secondary to primary nuclei ratios (e.g., B/C) produce too few antiprotons. In the present paper, we discuss one possibility to overcome these difficulties. Using the measured antiproton flux and B/C ratio to fix the diffusion coefficient, we show that the spectra of primary nuclei as measured in the heliosphere may contain a fresh local “unprocessed” component at low energies perhaps associated with the Local Bubble, thus decreasing the measured secondary to primary nuclei ratio. The independent evidence for SN activity in the solar vicinity in the last few Myr supports this idea. The model reproduces antiprotons, B/C ratio, and elemental abundances up to Ni (Z ⩽ 28). Calculated isotopic distributions of Be and B are in perfect agreement with CR data. The abundances of three “radioactive clock” isotopes in CR, 10Be, 26Al, 36Cl, are all consistent and indicate a halo size zh â¼Â 4 kpc based on the most accurate data taken by the ACE spacecraft.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Space and Planetary Science
Authors
I.V. Moskalenko, A.W. Strong, J.F. Ormes, S.G. Mashnik,