Moreover, we find that adopting the 3.722084 day period, all the available measurements of are in phase even if they present a different average value . On the contrary, the 3.7218 day period is not representative of the variability for the oldest measurements. CS Vir is classified as an A9SrEuCr star. Because of the different photometric systems, we have preferred to look for the period which gives an equal phase for the minimum of Stibbs', B and v light curves. A 0 coefficients of Eq.
Empty circles represent our photometric data.
We note that the U and B light curves are single-waves which are out of phase with respect to the variation. The V variation is a double-wave whose two maxima show the phase of extrema, the maximum coinciding with the positive magnetic extremum is slightly larger than the other one. It is worthy to note that the amplitudes of the V and y variations are comparable, and that the y light curve shows a primary maximum at the phase of the negative magnetic extremum and that the secondary maximum is much smaller than the primary one. Moreover, the u variation presents a secondary maximum that is not observed in the U variation. According to Catalano et al.