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[en] Displacement Damage Dose is the parameter used to quantify Displacement Damage effects on electrical and electronic systems. The method for calculating Displacement Damage Equivalent particle Fluence are presented, which is used to characterize the displacement damage dose induced by the radiation environment on orbit. The characteristics of three different Solar Particle Fluence Models are proposed by the analysis of results. The displacement damage doses on typical satellite orbits are calculated and the characteristics of radiation environment relevant of displacement damage are analyzed, Providing a reference for radiation hardness assurance for space systems. (authors)
[en] An overview of shock acceleration is presented, focusing primarily on interplanetary shocks and the termination shock as examples. An extended discussion of recent advances in modeling real solar energetic particle (SEP) and energetic storm particle (ESP) events is presented. When the energy of accelerated particles becomes very large, their back reaction on the flow can result in a shock that is significantly mediated, and as an example, we consider some results for the termination shock
[en] Complete text of publication follows. Using a new precise reconstruction of the energy spectrum of major solar energetic particle (SEP) events, based on thorough fitting of a wide set of data from ground-based and space-borne instrumentations, we quantitatively evaluate the possible effect of the SEP events on the low and middle atmosphere. The computations of the effect are based on the numerical 3D OuluCRAC:CRII model. It is shown that the direct ionization effect is negligible or even negative, due to the accompanying Forbush decreases, in all low- and mid-latitude regions. The effect is positive only in polar atmosphere, where it can be dramatic in the upper atmosphere during major SEP events.
[en] The experimental data on time dependences of high energy solar cosmic ray /SCR/ intensity and anisotropy agree with the suggestion that the constant of coronal SCR propagation, Bsub(m), is characteristic of injection into interplanetary space rather than diffusion of SCR in the solar corona
[en] Energetic particle populations are important constituents of solar, circumplanetary, interplanetary and distant heliospheric plasma structures, and at the same time provide valuable tools for testing models of galactic and universal acceleration and propagation processes. Although both the maximum energies and the variety of plasma processes are restricted by the relatively small size and energy supply of the solar system, these limitations are partly compensated by the superior spatial, temporal, directional and charge state information available for these particles. Both in situ and remote sensing observations contribute to our understanding. Recent advances in these fields will be reviewed, and the expected impact of current and future missions discussed
[en] A technique for estimating the equatorial connection longitude of interplanetary field lines to the corona is applied to quasi-stationary low-energy solar charged particle (LFSP) events to reconstruct their coronal injection profile. Comparison with synoptic charts constructed from Hα chromospheric absorption features for solar rotation 1524 reveals that the inferred chromospheric equatorial magnetic neutral line structure strikingly orders the LFSP coronal injection profiles of greater than or equal to 0.3 MeV protons for this period (August 1967), allowing the identification of acceleration processes lasting several days and well-defined coronal transport over greater than or equal to 1000. It is also proposed that LFSP observations offer a unique tool for studying the magnetic structure of the transition region from the low corona to interplanetary space. (U.S.)
[en] It is the intent of this review to cover major developments in American research related to solar energetic particles, both observational and theoretical, during the last four years (late 1978 to late 1982)
[en] Solar particle events that are rich in 3He typically also exhibit large overabundances of heavy and ultraheavy ions that increase with the mass of the ions. To explain these observations we apply our charge-consistent acceleration model, which takes into account the acceleration efficiency as a function of the charge to mass ratio of the ion, as well as the charge-dependent Coulomb energy losses, to consider the acceleration of ions within a wide range of their nuclear charge. Because the considerations of particle acceleration were restricted so far by tabulated values of ionization and recombination coefficients that were available only for a limited set of ions, we make use of our method developed earlier and calculate the rates of ions resembling the three representative mass groups of ultraheavy ions. We demonstrate that smaller Coulomb losses together with higher acceleration efficiency result in the enhancements of heavy and ultraheavy ions, in accordance with recent observations. We also conclude that the existing measurements of ultraheavy ions in impulsive solar energetic particle events provide evidence in favor of a magnetic turbulence in the acceleration region with spectral index S ≥ 2.