Meridional flow: Perturbed mode frequencies and eigenfunctions

Abstract

Two models for components of the meridional circulation in the Sun obeying the continuity equation are used for studying the effect of these large-scale flow models on solar p-modes. The models adapt major properties of meridional circulation cells in simulations of global solar convection. The perturbation effect of these models on the solar eigenstates and eigenfrequencies is determined by quasi-degenerate perturbation theory. The general finding is that determining the frequency multiplets of the solar p-modes, the two meridional circulation models lead on average to negative frequency shifts of the multiplets. The relative mean frequency shift δν/ν is less than 2×10 −5 . Investigating the eigenfunction, the perturbation is in the order of 10 −4 .