ИСТИНА

Space radiation can cause upsets in on-board spacecraft electronics (SCE) which can vary from short time transient effects to burn-out of the electronics components. A wide spectrum of the radiation types, mass and energy of the particles, versatile design of the electronic and constructive components make the estimation of the probability and category of possible upsets a difficult task. In particular, the passage of the high energy (~ 100 MeV) protons does not cause a large ionization in a solid target. In contrast, recoils, originated from either elastic collisions or nuclear reactions, having a large mass and a smaller energy, generate much more ionization eh pairs, enough to cause an upset in SCE. Here we consider shortly the basics and limitation of the linear-energy transfer (LET) conception. The LET conception must be extended to include ionizing effects of the recoils in nuclear elastic scattering and residual nuclei from nuclear reactions between incident protons and atomic nuclei of SCE materials. An advanced program based on modern nuclear data base can help to provide distributions of the residuals over charge, mass and kinetic energy, which can be used to estimate the probability and rate of the Single Event Effects (SEE). It is shown that these data can be used to estimate the upset volume and predict whether a single bit or multiple bits will be upset in a device with certain radiation hardness. A possible contribution of extreme fluctuations in ionizing power of the incident particles in the SCE material is also discussed.