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Solar Physics

, Volume 194, Issue 2, pp 405–413 | Cite as

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

  • Raúl Gómez-Herrero
  • M. Dolores RodrÍguez-FrÍas
  • Luis del Peral
  • Juan Sequeiros
  • Reinhold Müller-Mellin
  • Horst Kunow
  • Holger Sierks
Article

Abstract

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 2H/1H, 3He/4He, and 4He/1H have been calculated. The energy spectra in the 4–50 MeV nucl−1 range have been obtained and the contribution of the different spectral components have been analysed in this energy range. We conclude that the main contribution to the 4He spectrum is of anomalous origin, while the proton and 3He spectra have contributions mainly from particles of solar origin at low energies and from the galactic cosmic radiation modulated by the heliosphere at high energies. The deuterium spectrum is mainly of galactic origin.

Keywords

Hydrogen Helium Isotopic Composition Energy Spectrum Deuterium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Raúl Gómez-Herrero
    • 1
  • M. Dolores RodrÍguez-FrÍas
    • 1
  • Luis del Peral
    • 1
  • Juan Sequeiros
    • 1
  • Reinhold Müller-Mellin
    • 2
  • Horst Kunow
    • 2
  • Holger Sierks
    • 2
  1. 1.Departamento de FísicaUniversidad de AlcaláAlcalá de Henares, MadridSpain
  2. 2.Institut für Reine und Angewandte KernphysikKielGermany

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