mCP stars with photometrically simple behaviour

Abstract

We analyzed ubvy and Hp light curves of 19 well-observed magnetic CP stars selected from the On-line Database of Photometric Observations of mCP Stars, of which light curves in all the five colours were similar.We assumed that among these stars with photometrically simple behaviour (PSB) could be found ones with a single photometric spot. The knowledge gained by analysing those simple situations would help us comprehend more complicated cases. Light curves of the 19 PSB mCP stars proved generally to be nearly symmetrical, but surprisingly diverse. The analysis shows that only in the case of HD110956B, HD188041, and perhaps HD193722 are we able to explain their photometric behaviour by a simple one-spot model. Occurrence of more than one photometric spot on an mCP star is therefore more typical.