Monitoring of X-Ray Sources in the Optical Spectral Region
(a) Evolution of the peak magnitude of the outbursts in CH UMa. The bright and faint outbursts are marked by closed and open circles, respectively. (b) The O–C diagram (defined in Section 2.4) for the outbursts in CH UMa. The ephemeris is included in the title of the abscissa. The bright and faint outbursts are resolved. The O–C values of the faint outbursts are negative (positive) if they occurred before (after) the following (preceding) bright outburst. The faint outbursts are connected with the bright outburst, having the same epoch number, by a line for clarity. Adapted from .