Precision Stellar Astrophysics in the Kepler Era

TL;DR

This paper reviews observational methods like asteroseismology and interferometry for studying stellar properties, highlighting recent discoveries, their reliability, and the synergy between these techniques, with implications for astrophysics and exoplanet research.

Contribution

It provides an overview of recent advances in asteroseismology and interferometry, including new measurements and the potential of combined methods for stellar characterization.

Findings

Measurement of core rotation rates in red giants

Consistent stellar diameters across instruments for HD219134

Synergy between asteroseismology and interferometry enhances stellar models

Abstract

The study of fundamental properties (such as temperatures, radii, masses, and ages) and interior processes (such as convection and angular momentum transport) of stars has implications on various topics in astrophysics, ranging from the evolution of galaxies to understanding exoplanets. In this contribution I will review the basic principles of two key observational methods for constraining fundamental and interior properties of single field stars: the study stellar oscillations (asteroseismology) and optical long-baseline interferometry. I will highlight recent breakthrough discoveries in asteroseismology such as the measurement of core rotation rates in red giants and the characterization of exoplanet systems. I will furthermore comment on the reliability of interferometry as a tool to calibrate indirect methods to estimate fundamental properties, and present a new angular diameter measurement for the exoplanet host star HD219134 which demonstrates that diameters for stars which are relatively well resolved (~> 1 mas for the K band) are consistent across different instruments. Finally I will discuss the synergy between asteroseismology and interferometry to test asteroseismic scaling relations, and give a brief outlook on the expected impact of space-based missions such as K2, TESS and Gaia.