Touchstone Stars: Highlights from the Cool Stars 18 Splinter Session

TL;DR

This paper summarizes methods and recent findings related to 'touchstone stars' with directly measured parameters, emphasizing their role in calibrating models of cool star properties and highlighting discrepancies with theoretical predictions.

Contribution

It provides a comprehensive overview of techniques for measuring cool star parameters and discusses recent results and ongoing efforts to use these stars as benchmarks for stellar models.

Findings

Identification of new touchstone stars with precise measurements

Comparison reveals some discrepancies between observations and models

Ongoing efforts to refine stellar parameter determinations

Abstract

We present a summary of the splinter session on "touchstone stars" -- stars with directly measured parameters -- that was organized as part of the Cool Stars 18 conference. We discuss several methods to precisely determine cool star properties such as masses and radii from eclipsing binaries, and radii and effective temperatures from interferometry. We highlight recent results in identifying and measuring parameters for touchstone stars, and ongoing efforts to use touchstone stars to determine parameters for other stars. We conclude by comparing the results of touchstone stars with cool star models, noting some unusual patterns in the differences.