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.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bronchalo, E. et al.: 1999, Nuclear Instrument and Methods in Phys. Res. A 425, 361.
del Peral, L. et al.: 1998, Rayos Có smicos 98, Proc. 16th ECRS, pp. 185–188.
Fisk, L. et al.: 1974, Astrophys. J. L35, 190.
Fisk, L. et al.: 1998, Cosmic Rays in the Heliosphere, Kluwer Academic Publishers, Dordrecht, Holland.
Mason, G. M. et al.: 1986, Astrophys. J. 303, 849.
McGuire, R. E. et al.: 1986, Astrophys. J. 301, 938.
Moraal, H. et al.: 1999, Proc 26th Int. Cosmic Ray Conf. 7, 543.
Müller-Mellin, R. et al.: 1997, Proc 25th Int. Cosmic Ray Conf. 1, 301.
Müller-Mellin, R. et al.:1995, Solar Phys. 162, 483.
Ogawa, H. S. et al.: 1998, Geophys. Res. 103 (A1), 1.
Pesses, M. E. et al.: 1981, Astrophys. J. 85, 246.
Reames, D. V.: 1993, Proc. 23nd Int. Cosmic Ray Conf. 3, 388.
Seo, et al.: 1994, Astrophys. J. 432, 656.
Sierks, H.: 1997, Kosmische Teilchen in Sonnensystem, PhD Thesis. University of Kiel (in German).
Steenberg, C. D. and Moraal, H.: 1996, Astrophys. J. 463, 776.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Gómez-Herrero, R., RodrÍguez-FrÍas, M.D., del Peral, L. et al. Quiet-time periods observed by EPHIN/SOHO during the minimum of the 22nd solar cycle. Solar Physics 194, 405–413 (2000). https://doi.org/10.1023/A:1005244720379
Published:
Issue Date:
DOI: https://doi.org/10.1023/A:1005244720379