Types of Interplanetary Shocks and Forbush Decreases
Abstract
Two types of interplanetary shocks have been identified and classified into two groups, those associated with a helium-enhancement and those not associated with any helium-enhancement. The cosmic-ray intensity decreases at Calgary neutron monitor are studied with respect to the arrival time of the two groups of shocks. The observations show that large Forbush decreases are caused by shocks associated with the helium-enhancement; and those not associated with He shocks show comparatively a small decrease in cosmic-ray intensity.
- Publication:
-
Solar Physics
- Pub Date:
- August 1991
- DOI:
- 10.1007/BF00152655
- Bibcode:
- 1991SoPh..134..395B
- Keywords:
-
- Cosmic Rays;
- Forbush Decreases;
- Interplanetary Medium;
- Shock Fronts;
- Helium;
- Interplanetary Magnetic Fields;
- Space Plasmas;
- Space Radiation