A relation between frequency shift and the changes in activity indices

Abstract

We present a linear relation between the shift in p-mode frequencies and variation in two solar activity indices, namely the sunspot number and 10.7 cm radio flux. From this relation, an empirical model is constructed to estimate the mean frequency shifts with respect to activity index. We also compare the observed and estimated shifts for solar cycle 22 and comment on the systematic errors in different helioseismic data sets.