Observation of the electron to alpha-particle ratio as a test for solar modulation

Publisher Website
Google Scholar
Abstract
The electron to alpha-particle ratio is a sensitive parameter for examining the mechanism of solar modulation. Our balloon-borne detector designed for the detection of primary electrons (0.5–30 GeV) can also register alpha particles with a rigidity above 1.7 GV. These alpha particles are selected from the recorded events unambiguously by means of an analysis of the simultaneous ionization losses in three plastic scintillators. Several balloon flights have been carried out from Kiruna, Sweden (geomagnetic cutoff 0.5 GV) in 1965 and 1966. Electron observations from flights in subsequent years do not indicate a significant modulation of electrons above 500 MeV, whereas the alpha particles show a modulation of 15 ± 3%. The results are not in agreement with a purely rigidity-dependent modulation mechanism.

This publication has 1 reference indexed in Scilit: