The Light-Time Effect in Astrophysics, Proceedings of ASP Conference Series vol:335 pages:95-102
Proceedings of ASP Conference Series
The Light-Time Effect in Astrophysics location:Brussels, Belgium date:19-22 July 2004
Almost a century after its discovery, the phenomenon of amplitude and/or phase modulation, observed in a large percentage of the RR Lyrae stars, still lacks widely acceptable theoretical understanding. Recent attempts to theoretically explain the effect focus on two alternatives: the magnetic models and the resonances models, both involving the presence of nonradial pulsation components.
In this paper the Blazhko Project is presented, a larger international collaboration focused on understanding the Blazhko effect. The aim of the project is to combine spectroscopic and photometric data from a sample of well-selected Blazhko and non-Blazhko stars, in order to reveal crucial information on the physical mechanism responsible for the modulation.
The possible key to the century-old Blazhko puzzle lies in the detailed study of the line profile variations (LPV) over the pulsation and Blazhko cycle. We briefly discuss the methodology of the project.