Magnetic activity under tidal influences in the 2+2~hierarchical quadruple system V815 Herculis

TL;DR

This study investigates how tidal forces in the complex quadruple star system V815 Herculis influence magnetic activity and dynamo processes in the magnetically active star, providing insights into stellar magnetic behavior under gravitational influences.

Contribution

It offers new observational insights into the effects of tidal forces on magnetic activity in a hierarchical quadruple system with multiple close binaries.

Findings

Tidal forces can enhance or suppress magnetic dynamo activity.

Synchronization maintains rapid rotation, supporting dynamo efficiency.

Tidal influences may induce active longitudes at specific orbital phases.

Abstract

Tidal forces in close binaries and multiple systems that contain magnetically active component are supposed to influence the operation of magnetic dynamo. Through synchronization the tidal effect of a close companion helps maintain fast rotation, thus supporting an efficient dynamo. At the same time, it can also suppress the differential rotation of the convection zone, or even force the formation of active longitudes at certain phases fixed to the orbit. V815 Her is a four-star system consisting of two close binaries orbiting each other, one of which contains an active G-type main-sequence star. Therefore, the system offers an excellent opportunity to investigate the influence of gravitational effects on solar-type magnetic activity using different methods.