Single event effects (SEEs) in ground level and avionic applications are mainly induced\nby neutrons and protons, of which the relative contribution of the latter is larger with increasing\naltitude. Currently, there are two main applicable standards--JEDEC JESD89A for ground level and\nIEC 62396 for avionics--that address the procedure for testing and qualifying electronics for these\nenvironments. In this work, we extracted terrestrial spectra at different altitudes from simulations\nand compared them with data available from the standards. Second, we computed the SEE rate\nusing different approaches for three static random access memory (SRAM) types, which present a\nstrong SEE response dependence with energy. Due to the presence of tungsten, a fissile material when\ninteracting with high energy hadrons, the neutron and proton SEE cross sections do not saturate after\n200 MeV, but still increase up to several GeV. For these memories, we found standard procedures\ncould underestimate the SEE rate by a factor of up to 4-even in ground level applications--and up to\n12 times at 12 km. Moreover, for such memories, the contribution from high energy protons is able to\nplay a significant role, comparable to that of neutrons, even at commercial flight altitudes, and greater\nat higher altitudes.
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