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We publish 16 Doppler imaging temperature maps for the years 1994-2002 of theactive RS CVn star II Peg. The six maps from 1999-2002 are based on previouslyunpublished observations. Through Doppler imaging we want to study the spotevolution of the star and in particular compare this with previous resultsshowing a cyclic spot behaviour and persistent active longitudes. Theobservations were collected with the SOFIN spectrograph at the Nordic OpticalTelescope. The temperature maps were calculated using a Doppler imaging codebased on Tikhonov regularization. During 1994-2001, our results show aconsistent trend in the derived longitudes of the principal and secondarytemperature minima over time such that the magnetic structure appears to rotatesomewhat more rapidly than the orbital period of this close binary. A suddenphase jump of the active region occured between the observing seasons of 2001and 2002. No clear trend over time is detected in the derived latitudes of thespots, indicating that the systematic motion could be related to the drift ofthe spot generating mechanism rather than to differential rotation. The derivedtemperature maps are quite similar to the ones obtained earlier with adifferent methods, the main differences occurring in the spot latitudes andrelative strength of the spot structures. We observe both longitude andlatitude shifts in the spot activity of II Peg. However, our results are notconsistent with the periodic behaviour presented in previous studies.

Doppler images of the RS CVn binary II Pegasi during the years 1994-2002