Proton single event upset (SEU) cross sections and proton total dose hardness of commercially available MIPS R3000 microprocessors (CPU) and R3010 floating point units (FPU) were obtained by exposing these parts to 256 MeV protons from the linear accelerator (LINAC) at the Los Alamos Meson Physics Facility (LAMPF). Parts from several manufacturers were tested. The CPUs and FPUs were tested dynamically during radiation exposure with specially designed assembly language codes which exercised a subset of the available instructions. Cross sections derived from the SEU data were used to calculate expected upset rates for a 500-km, 60-degree inclination, orbit during quiet solar conditions and during the August 4, 1972, King solar flare event [12, 13] modeled by Adams et al. [14].

Cumulative fractions for linear energy transfer spectra were measured for particles ejected from microelectronics packaging materials subjected to neutron and proton irradiations. The measurements for the neutron irradiations compare well with Monte Carlo theoretical calculations. The spectra can be used to access microelectronics vulnerabilities in strategic-nuclear-weapon, space-trapped, and neu...

Neutron yields from proton bombardment of elemental Pb and depleted U have been measured at bombarding energies of 318 and 800 MeV. Additionally, at 800 MeV, data were obtained for Al and C. The data were obtained at angles/flight-paths of 7.5deg/30m and 30deg/40m and were collected in two parameter histograms of tine-of-flight and pulse-height in order to select detector biases in the analysis and to permit comparison of calculated and experimental pulse height spectra in the calculation of detector efficiency. The data have been reduced to absolute double-differential cross sections and are in good agreement with INC calculations at 800 MeV but exceed calculation by a factor of three at the lower energy.