Abstract:
We have examined theWilson effect in 580 epochs of sunspots observed at the Kodaikanal Observatory. Only unipolar spots that are well isolated from opposite polarity spots or pores (49%) exhibit the classic Wilson effect. The larger the isolation, the stronger is the effect. Unipolar spots also show a decrement of the effect that seems to be related to age. However, bipolar spots (45%) do not display theWilson effect, while spots associated with a mixed-polarity magnetic configuration (6%) show an inverse effect. We are now studying dynamic responses of spot penumbrae to their ambient magnetic configuration.
