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The Phosphorus, Sulfur, Argon, and Calcium Isotopic Composition of the Galactic Cosmic Ray Source

“…Previously calculated cosmic ray source abundances, where available, were used for q i in Equation (1) (as in Wiedenbeck et al 2001b), and solar system composition with fractionation effects was assumed for those nuclides i where nominal cosmic ray abundances are not known. Energy-dependent cross-section measurements are needed to calculate the spallation of a nucleus to a lighter species due to collisions with particles in the ISM (assumed to be 90% hydrogen and 10% helium by number).…”

“…The elemental and isotopic GCR composition, measured with high precision in recent years by satellite experiments (Engelmann et al 1990;George et al 2009;Wiedenbeck et al 2001bWiedenbeck et al , 2007a, is similar to solar system material for many species but differs significantly for others. Any theory for the proposed GCR source environment and acceleration mechanism must be consistent with modern measurements over the ensemble of GCR species.…”

Elemental and isotopic composition measurements of galactic cosmic rays

“…Measurements of isotopic composition showed, in most cases, that nuclidic abundances in cosmic ray source material closely resemble those found in the solar system [24,21]. One striking exception was found: the abundance ratio 22 Ne/ 20 Ne is strongly enhanced [32,33,34], exceeding the solar wind value by a factor ∼5.…”

“…One of the early motivations for studying the isotopic composition of cosmic rays was the hope that the source material might bear compositional signatures associated with a particular nucleosynthesis process and thus help in identifying a class of stellar objects responsible for the origin and acceleration of GCRs. However, the observations showed that the cosmic ray source contains contributions from a wide range of nucleosynthesis processes (as does the solar system) and provided a strong indication that cosmic rays are an accelerated sample of interstellar matter [24,25]. Thus recent work has concentrated on searching for differences between GCR source and solar system composition that could probe the physical conditions peculiar to the origin of these two samples of interstellar material.…”

Enhanced gamma ray signals in cosmic proton-wimp collisions due to hadronization

“…For details see Appendix A. We choose two template Galprop CR profiles, the plain diffusion model 999726 [20] and diffusion-reacceleration model 599278 [21] to calculate the integrated strength of gamma ray source, J(θ)dθ in Fermi's angular windows [22], as shown in Tab. I.…”