A spectral solver for solar inertial waves

TL;DR

This paper introduces a spectral eigenvalue solver for modeling solar inertial waves, enabling better understanding of solar subsurface dynamics through accurate mode frequency and linewidth predictions.

Contribution

The work presents a novel spectral solver that models inertial modes in the Sun's convection zone, reproducing observed frequencies and linewidths, including high-frequency inertial modes.

Findings

Reproduces observed mode frequencies and linewidths

Successfully models high-frequency inertial modes

Provides a new numerical tool for solar inertial wave analysis

Abstract

Inertial waves, which are dominantly driven by the Coriolis force, likely play an important role in solar dynamics, and additionally, provide a window into the solar subsurface. The latter allows us to infer properties that are inaccessible to the traditional technique of acoustic-wave helioseismology. Thus, a full characterization of these normal modes holds promise in enabling the investigation of solar subsurface dynamics. In this work, we develop a spectral eigenvalue solver to model the spectrum of inertial waves in the Sun. We model the solar convection zone as an anelastic medium, and solve for the normal modes of the momentum and energy equations. We demonstrate that the solver can reproduce the observed mode frequencies and line-widths well, not only of sectoral Rossby modes, but also the recently observed high-frequency inertial modes. In addition, we believe that the spectral solver is a useful contribution to the numerical methods on modeling inertial modes on the Sun.