Daily Variation of Tilt Angles of Sunspot Groups

Abstract

The influence of polarity separation on the daily tilt angle variation of sunspot groups has been studied from a selected number of observations of the Sun spanning the entire 22nd solar cycle. Daily white-light images of the Sun from Kodaikanal Observatory have been utilized to obtain both polarity separation and axial tilt of sunspot groups. Over 100 long-lived spot groups that had well distinct leading and following parts are chosen from different latitude belts for this purpose. Variation of tilt angle with polarity separation has been studied after classifying the spot groups according to its age and area. Preliminary results of this analysis are discussed in this paper.