Inverse analysis of asteroseismic data: a review

TL;DR

This review discusses how inverse analysis of asteroseismic data can reveal detailed internal stellar structures, helping to improve stellar evolution models by identifying discrepancies between theory and observations.

Contribution

It provides an overview of asteroseismic inversion methods and highlights recent progress in measuring stellar interiors to refine models.

Findings

Asteroseismic inversions can identify internal structural discrepancies.

Comparison of models and observations guides improvements in stellar physics.

Progress is being made in measuring stellar interiors with inversion techniques.

Abstract

Asteroseismology has emerged as the best way to characterize the global and internal properties of nearby stars. Often, this characterization is achieved by fitting stellar evolution models to asteroseismic observations. The star under investigation is then assumed to have the properties of the best-fitting model, such as its age. However, the models do not fit the observations perfectly. This is due to incorrect or missing physics in stellar evolution calculations, resulting in predicted stellar structures that are discrepant with reality. Through an inverse analysis of the asteroseismic data, it is possible to go further than fitting stellar models, and instead infer details about the actual internal structure of the star at some locations in its interior. Comparing theoretical and observed stellar structures then enables the determination of the locations where the stellar models have discrepant structure, and illuminates a path for improvements to our understanding of stellar evolution. In this invited review, we describe the methods of asteroseismic inversions, and outline the progress that is being made towards measuring the interiors of stars.