Blazhko Effect in Double Mode Cepheids

Abstract

Systematic survey for multiperiodicity in the LMC Cepheids (Moskalik, Kolaczkowski & Mizerski 2004, 2006) has led to discovery of several new forms of pulsational behaviour. One of them is periodic amplitude and phase modulation observed in many first/second overtone (FO/SO) double mode Cepheids. In the current paper we present detailed discussion of this newly discovered phenomenon, based on a combined OGLE+MACHO sample of double mode pulsators.

8 pages, 4 figures. Invited talk presented at workshop, "Nonlinear Stellar Hydrodynamics", 9-11 July 2007, Paris, France, to appear in EAS Publication Series