Stellar Activity Cycles

TL;DR

This review discusses how stellar magnetic activity cycles, similar to the Sun's 11-22 year cycle, are observed and analyzed across different stars using various diagnostics like magnetic field mapping, chromospheric and coronal indicators, photometry, and asteroseismology.

Contribution

It synthesizes current knowledge on stellar magnetic cycles and highlights diagnostic techniques used to study stars with solar-like internal structures.

Findings

Mapping surface magnetic fields reveals cycle patterns.

Chromospheric and coronal indicators correlate with magnetic activity.

Asteroseismology provides insights into internal magnetic processes.

Abstract

The magnetic field of the Sun is generated by internal dynamo process with a cyclic period of 11 years or a 22 year magnetic cycle. The signatures of the Sun's magnetic cycle are observed in the different layers of its atmosphere and in its internal layers. In this review, we use the same diagnostics to understand the magnetic cycles of other stars with the same internal structure as the Sun. We review what is currently known about mapping the surface magnetic fields, chromospheric and coronal indicators, cycles in photometry and asteroseismology. We conclude our review with an outlook for the future.