Cosmic-Ray Modulation and Solar LDE-Type Flares

Abstract

Cross-correlation analyses between galactic cosmic-ray intensities from Calgary neutron monitor and several solar-activity parameters, on daily basis, have been undertaken. We report here results connected with the unresolved full-solar X-Ray background and the occurrence of solar LDE-type flares (both from GOES-satellite data) in the time interval July 1988-June 1989 (i.e. the last part of the ascending phase of sunspot cycle 22). Our findings do not support the hypothesis that LDE-type flare occurrence is the best parameter to describe the medium-term modulation of galactic cosmic rays; however, it could be a good indicator of sudden but stable coronal variations occurring along the solar-activity cycle, i.e. a proxy data set to include peculiar transient-induced effects on the long-term cosmic-ray modulation studies.