No CrossRef data available.
Published online by Cambridge University Press: 20 April 2012
The GEOS data base for RR Lyr stars has been analysed to search for secondary (Blazhko) periods in several stars for which over 100 years of measurements are available. The results indicate that, even when there is a secondary period present, its behaviour can be dramatically different from star to star or even over time in the same star. In one star there is a clear correlation between the O–C diagrams for both the pulsation and Blazko periods; that has implications for the origins of the Blazhko periods.