Three-colour photoelectric photometry of the RRab variable star RV Ursae Majoris is presented. Period and total light curve changes of the star during the Blazhko period and O-C diagrams of both the main and the secondary periods are investigated. It was found that a certain phase point (Phi_s = 0.94) of the ascending branches of the light curves showed no oscillation during the Blazhko period, which is hardly compatible with the assumption of the superposition of beat periods. A long cycle of 6-8 years in the O-C variations of the ascending branch was also found. Similar long cycle variations are shown by other RR Lyrae stars exhibiting the Blazhko effect, this variation being reminiscent of the solar magnetic cycle.
Commmunications of the Konkoly Observatory Hungary
- Pub Date:
- January 1976