A correlative study on the last four solar cycles

We studied cosmic ray intensity and its amplitude, dispersion and phase as function of the corresponding solar parameters. The investigation was performed in terms of the last four solar cycles (20, 21, 22 and 23) over the long term periods (1964 - June, 2007). To an extent, cutoff rigidities of cosmic ray particles from 1968 through 2006 are determined to look into the status in the positions of solar cycle maximum and minimum. During solar maximum the solar wind proton is directly while during solar minimum inversely related to the geomagnetic indices. Solar wind temperature has much greater effective roles during solar minimum than during solar maximum. Solar cycle 20 has lots of differences from other solar cycles. The mini and descending phase cycles are effective in solar cycle 20 which are seemingly occurred during the time of heliospheric neutrally flat sheet. The minicycle existing within the declining phase cycle is the parts of causative solar activities related to additionally important research over cosmic ray diurnal variations. In the minicycle the highest upper cutoffs and also comparatively higher effective cutoffs undergo. Cycle 21 and 22 are also found different from other solar cycles where both maximum and minimum do not fully obey the inverse law of the summation of solar activity and cosmic ray intensity. The activities of solar parameters have different impacts on the ascending and descending phase of the same solar cycle with differences in fluctuations of cutoff rigidities. There are rare events within solar cycles where the usual relations between cosmic ray and solar parameters are not obeyed. Few authors earlier explained more details with two solar activity cycles, separating the data into parts corresponding to fast and slow solar wind while other authors made a search into odd and even cycles of cosmic rays and solar activity. Ascending and descending phases of solar cycles are also deal talong with ´minicycle´ and ´declining´ pha- - se cycle. The data analysis is done by the mathematical expression.