Cosmic Rays, the Sun and Geomagnetism

Résumé du livre

Published by the American Geophysical Union as part of the Special Publications Series.

This monograph is a tribute to the character and achievements of Scott Ellsworth Forbush (1904-1984) who, almost single-handedly with only technical assistance, laid the observational foundations for an important part of the subject of solar-interplanetary-terrestrial physics. The heart of his research was the meticulous and statistically sophisticated analysis of the temporal variations of cosmic-ray intensity as measured by ground-based detectors at various latitudes and altitudes.

Forbush either discovered or put on a firm basis for the first time the following fundamental cosmic-ray effects: The quasi-persistent 27-day variation of intensity.The diurnal variation of intensity. The sporadic emission of very energetic (up to ≈GeV) protons by solar flares. Worldwide impulsive decreases (Forbush decreases) in intensity followed by gradual recovery. The 11-year cycle of intensity and its anticorrelation with the solar activity cycle as measured by sunspot numbers. The 22-year cycle in the amplitude of the diurnal variations.