Evolution of Solar-Type Activity: Acoustic and Magnetic Energy Generation and Propagation in Beta Hydri (G2 IV)

TL;DR

This paper investigates the acoustic and magnetic energy processes in beta Hydri, a star similar to the Sun, to understand stellar activity evolution and compare it with solar behavior, highlighting gravity's role in acoustic energy generation.

Contribution

It provides new insights into magnetic and acoustic energy fluxes in beta Hydri, emphasizing gravity effects and height-dependent magnetic flux behavior, advancing stellar activity modeling.

Findings

Acoustic energy flux differences between beta Hydri and the Sun are smaller than in main-sequence stars.

Gravity significantly influences acoustic energy generation in evolved stars.

Magnetic flux fluxes vary with height and flux tube spreading.

Abstract

We examine the acoustic and magnetic energy generation and propagation in beta Hydri (G2 IV). The underlying motivation for this work is based on the solar, stellar, and galactic relevance of beta Hydri (a star in the Southern hemisphere), which is readily understood as a prime example and proxy of the future Sun - thus allowing assessments and analyses of the secular decay of solar activity. Regarding the magnetic energy generation, we consider longitudinal flux tube waves. We also assess acoustic waves. For the acoustic wave energy flux, the difference between the results obtained for beta Hydri and the Sun is significantly smaller than typically attained for main-sequence stars, which is largely due to the gravity-dependence of the acoustic energy generation. Furthermore, we study the height-dependent behavior of the magnetic energy flux for different magnetic filling factors corresponding to different flux tube spreadings. Finally, we comment on possible directions of future research.