The diurnal effect of the cosmic rays during the period 15 oct. 1965 - 30 june 1966. a) Method of analysis and statistical distribution

An improved method of analysis of the diurnal variation of the C.R. has been developped starting from the one presented by Bachelet et al. (1967) at the International Calgary Conference. Instead of the usual numerical filtering techniques we have used the properties of the asymptotic cones of acceptance of high latitude Cosmic Ray (C.R.) stations. Then all the results have been collected into a matrix which could give a compact vision of the phenomenon on an horly basis. Because of the lack of stations in the asiatic and pacific area we limit our study to an "average diurnal variation wave". From the statistical distribution of daily values of the amplitude and phases of the anisotropy our conclusion agree with the preceding results of various authors and also show an unexpected trend for the direction of the minimum for days with half peak amplitudes of the anisotropy less or equal to 0.5%. A preliminary investigation on the North South anisotropy during Forbush decreases has also been done.