Low-dimensional dynamics outside the laboratory: The case of roAp stars

Abstract

In this work, we build a nonlinear model to account for the time variable energy flux of a class of pulsating stars which is simple and robust, and test it against recent observations made with the Hubble Space Telescope. By the construction of a standard global normal form for the model, we not only check that the model has solutions qualitatively similar to the observations; we also fit the parameters of the model from the time series. This allows us to build confidence on a simple model for the phenomenon under study, which should be valid for a class of pulsating stars.