Solar cosmic ray composition above 10 MeV/nucleon and its energy dependence in the 4 August 1972 event

CREME96: A Revision of the Cosmic Ray Effects on Micro-Electronics Code

“…Even the CREME96 "peak flux" model falls at least one order of magnitude below these old models. All heavy-ion fluxes above -40 MeV/nuc in the August 1972 event came from a single 4-minute sounding-rocket flight [42], [43], and there were no Fe measurements above -60 Finally, we also not [IO] contains new solar observations of the M those two events were much smaller than the October 1989 event used in CREME96. (The abundances.…”

Enhancement of solar heavy nuclei at high energies in the 4 July 1974 event

“…For purposes of comuarison with earlier mf:asurcments, it should be noted that the absolute fluxes of solar oxygen observed here arc approximately two orders of magnitude smaller than any previous observations in the SPICE program (Bertsch of al., 1973a(Bertsch of al., , 1974 The Fe/0 ratio determined in this manner is 39 9-9%. This ratio is clearly inconsistent with a ratio of 3 to 6% found in earlier (Bertsch et al, 1973a(Bertsch et al, , 1973b(Bertsch et al, , 1974) solar particle events" Had the latter ratio prevailed on 4 July 1974, the expected iron-group spectrum would be that shown by the dashed line in Figure 1.…”

“…Typical values of E. in earUer events (see Bertsch at al., 1974 and references therein) are factors of 2 to 3 larger than those found here.…”

“…Details of this technique have been reported earlier (see Bertsch et al, 1974). The main difference between the current experiment and earlier studies in the program is in the size of the emulsion stacks.…”

“…The 4 July abundances shown in Table I exhibit a systematic anhancement in the relative abundances of heavier nuclei when compared with most of the earlier measurements at comparable energies (Crawford at al., 1972;Teegarden at al., 1973;Bertsch at al., 1974). These enhancements are somewhat less pronounced, however, than those observed by Mogro-Campero and Simpson (1972a, b).…”