Role of coronal index of solar activity in long-term cosmic ray modulation

Abstract

The relationship between cosmic rays and coronal index of solar activity (CI) for the periods of negative (A < 0), mixed and positive (A > 0) polarities of the general magnetic field of sun has been analysed. In cosmic ray modulation, sunspot numbers are being generally used as a reliable solar parameter. In this analysis, coronal index has been used as a new solar parameter for long-term cosmic ray modulation. Negative and high correlations are found between CI and cosmic rays for the A > 0 epochs and A < 0 epochs of solar magnetic field. Significant differences are found between A > 0 and A < 0 epochs of solar magnetic field. Correlations are found to be poor during the mixed polarity years.