Modelling delta Scuti stars using asteroseismic space data

TL;DR

This paper introduces new modelling techniques for delta Scuti stars using space-based asteroseismic data, enabling precise density measurements and insights into stellar stability despite complex frequency spectra.

Contribution

The study develops methods to identify regular frequency patterns in delta Scuti stars, improving density estimates and understanding of their stability using space photometry.

Findings

Identified regular frequency patterns resembling large separation.

Achieved unprecedented accuracy in mean density determination.

Provided insights into the stability of delta Scuti stars.

Abstract

In the last years, space missions such as COROT, Kepler or MOST have provided very accurate photometric observational data. In the particular case of $\delta$ Scuti stars, the observed frequency spectra have hundreds (if not thousands) of modes and a clear amplitude distribution. In this work we present new techniques for modelling these observations and the results obtained. We searched for regular patterns in the observational data, which yields something resembling the large separation. This allows to reduce the possible positions of the star in the HR diagram, yielding a value of the mean density with an accuracy never reached before for isolated stars of this type. Finally, we answer whether a $\delta$ Scuti star is stable despite all of the observed frequencies are simultaneously excited.