Magnetic activity of seismic solar analogs

TL;DR

This study compares magnetic activity of 18 seismic solar analogs with the Sun, revealing similar activity levels and identifying short-term activity modulation in a young analog, enhancing understanding of solar-stellar magnetic connections.

Contribution

First detailed comparison of magnetic activity proxies between the Sun and seismic solar analogs, including detection of short-term activity modulation in a young analog.

Findings

The Sun's activity is comparable to seismic solar analogs.

Detected ~1.5-year activity modulation in a young solar analog.

KIC10644253 is a young, active star with short-term magnetic activity variations.

Abstract

We present our latest results on the solar-stellar connection by studying 18 solar analogs that we identified among the Kepler seismic sample (Salabert et al., 2016a). We measured their magnetic activity properties using observations collected by the Kepler satellite and the ground-based, high-resolution Hermes spectrograph. The photospheric (Sph) and chromospheric (S) magnetic activity proxies of these seismic solar analogs are compared in relation to solar activity. We show that the activity of the Sun is actually comparable to the activity of the seismic solar analogs. Furthermore, we report on the discovery of temporal variability in the acoustic frequencies of the young (1 Gyr-old) solar analog KIC10644253 with a modulation of about 1.5 years, which agrees with the derived photospheric activity (Salabert et al., 2016b). It could actually be the signature of the short-period modulation, or quasi-biennal oscillation, of its magnetic activity as observed in the Sun and the 1-Gyr-old solar analog HD30495. In addition, the lithium abundance and the chromospheric activity estimated from Hermes confirms that KIC10644253 is a young and more active star than the Sun.