Observing dynamos in cool stars

TL;DR

This paper reviews observational methods and data analysis techniques for studying stellar dynamos, comparing stellar data to solar observations, and discusses future prospects in the field.

Contribution

It provides an updated overview of observational approaches and data interpretation in stellar dynamo research since the last comprehensive review.

Findings

Comparison of stellar and solar data in consistent dimensions and wavelengths

Identification of limitations in current observational interpretations

Outline of future observational and modeling prospects

Abstract

The main aim of this paper is to introduce the most important observables that help us to investigate stellar dynamos and compare those to the modeling results. We give an overview of the available observational methods and data processing techniques that are suitable for such purposes, with touching upon examples of inadequate interpretations as well. Stellar observations are compared to the solar data in such a way, which ensures that the measurements are comparable in dimension, wavelength, and timescale. A brief outlook is given to the future plans and possibilities. A thorough review of this topic was published nearly a decade ago (Berdyugina 2005), now we focus on the experience that have been gathered since that time.