Quiet-time periods observed by EPHIN/SOHO during the minimum of the 22nd solar cycle

An analysis of the hydrogen and helium isotopic composition from EPHIN data , during the quiet-time period from January 1 to June 1, 1996, is presented . An isotopic discrimination and background rejection have been applied and relationships between the abundances of H-2/H-1, He-3/He-4, and He-4/H-1 h ave been calculated The energy spectra in the 4-50 MeV nucl(-1) range have been obtained and the contribution of the different spectral components hav e been analysed in this energy range. We conclude that the main contributio n to the He-4 spectrum is of anomalous origin, while the proton and He-3 sp ectra have contributions mainly from particles of solar origin at low energ ies and from the galactic cosmic radiation modulated by the heliosphere at high energies. The deuterium spectrum is mainly of galactic origin.