An alternative to mode fitting

TL;DR

This paper introduces a rapid, accurate alternative to mode fitting for analyzing stellar oscillations in CoRoT data, using envelope autocorrelation and filtering to determine large separations efficiently.

Contribution

The authors present a new method employing envelope autocorrelation and filtering to measure large separations, simplifying and speeding up the analysis process compared to traditional mode fitting.

Findings

Method is as accurate as mode fitting.

It effectively separates even and odd degree ridges.

The approach is easy to implement and computationally fast.

Abstract

The space mission CoRoT provides us with a large amount of high-duty cycle long-duration observations. Mode fitting has proven to be efficient for the complete and detailed analysis of the oscillation pattern, but remains time consuming. Furthermore, the photometric background due to granulation severely complicates the analysis. Therefore, we attempt to provide an alternative to mode fitting, for the determination of large separations. With the envelope autocorrelation function and a dedicated filter, it is possible to measure the variation of the large separation independently for the ridges with even and odd degrees. The method appears to be as accurate as the mode fitting. It can be very easily implemented and is very rapid.