Magnetic cycles of Sun-like stars with different levels of coronal and chromospheric activity -- comparison with the Sun

TL;DR

This study compares magnetic activity cycles of Sun-like stars across spectral types, revealing that K-stars exhibit more prominent cycles and that the Sun has uniquely low chromospheric and coronal activity levels among similar stars.

Contribution

It provides a comparative analysis of magnetic activity cycles in Sun-like stars, highlighting the Sun's distinct low activity levels and the prominence of cycles in K-type stars.

Findings

K-stars show more prominent cyclic activity.

The Sun has the lowest chromospheric activity among similar stars.

The Sun's coronal radiation and flux variations are minimal.

Abstract

The atmospheric activity of the Sun and Sun-like stars is analyzed involving observations from HK-project at the Mount Wilson Observatory, the California and Carnegie Planet Search Program at the Keck and Lick Observatories and the Magellan Planet Search Program at the Las Campanas Observatory. We show that for stars of F, G and K spectral classes, the cyclic activity, similar to the 11-yr solar cycles, is different: it becomes more prominent in K-stars. Comparative study of Sun-like stars with different levels of the chromospheric and coronal activity confirms that the Sun belongs to stars with the low level of the chromospheric activity and stands apart among these stars by the minimum level of its coronal radiation and the minimum level of its variations of the photospheric flux.