Matteo Cantiello edited Magnetic Trapping.tex  about 9 years ago

Commit id: 1d47b9f80cb795f1192f60fa397b7c3a8b49ce42

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We can now understand the behavior of waves and oscillation modes in red giants with magnetic cores. Waves with angular frequency $\omega \sim \omega_{\rm max}$ are excited via convective motions near the surface of the star. As in other red giants, the waves propagate downward as acoustic waves until their frequency is less than the local Lamb frequency for waves of angular degree $\ell$, i.e., until $\omega < L_{\ell}$. At this boundary, part of the wave flux is reflected, and part of it tunnels through.   The degree of reflection is determined by the tunneling integral through the evanescent region. The transmission coefficient is   \begin{equation}\label{eq:integral} \begin{equation}\label{eqn:integral}  T = \exp{\int^{r_2}_{r_1} i k_r dr} \simeq \exp{\int^{r_2}_{r_1} - \frac{\sqrt{\ell(\ell+1)}}{r} dr } \, ,  \end{equation}  where $r_1$ and $r_2$ are the boundaries of the evanescent region (in this case, the upper boundary occurs where $\omega