Simulation of long-term cosmic-ray intensity variation

✍ Scribed by H. Mavromichalaki; E. Marmatsouri; A. Vassilaki

• Publisher: Springer
• Year: 1990
• Tongue: English
• Weight: 322 KB
• Volume: 125
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00158416

✦ Synopsis

Selecting the most appropriate source functions among the various solar, interplanetary and terrestrial activity indices we have attempted to reproduce to a certain degree the long-term modulation of galactic cosmic-rays. For this study monthly cosmic-ray data from nine world-wide neutron monitor stations for the period 1975-1985 have been analysed. The empirical formula which has been used to compute the long-term cosmic-ray variations follows the observations fairly well.

It is noteworthy that the residuals in the cosmic-ray intensity between that observed and that calculated by this empirical formula exhibits a still remaining short-term variation in all stations of 2.7 and 3.7 months. Possible interpretations of these observed periodicities related to galactic origin are given.