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Validation of the code

Jørgen Christensen-Dalsgaard's Lecture Notes on Stellar Oscillations have a number of example eigenfunctions for selected oscillation modes in section 5.3 "Some Numerical Results". The code that was used to obtain these results solved the full forth order system of ordinary differential equations, as opposed to my code, which solves the equations under the Cowling approximation which reduces the problem to a second order system of ordinary differential equations. As explained here. I used the additional Matlab script to draw the scaled radial displacement eigenfunction as a function of the radius, from the output files.
Using Model S for the Sun, Christensen-Dalsgaard got \nu = 3310 \, \mu Hz for a mode order of n = 23 and angular degree of l = 0, together with the following scaled radial displacement eigenfunction:

From Figure 5.8 in Lectures Notes on Stellar Oscillations by J. Christensen-Dalsgaard
Notice that the figure doesn't display a scale for the y-axis. The reason for that is that the solution is correct up to some normalization factor. This renders the y-axis scale irrelevant.

Using the same Solar Model in my code, the search for a mode order of n = 23 and angular degree l = 0 resulted in \nu = 3335 \, \mu Hz and the following eigenfunction:
The figure was obtained by the project's code
Keeping in mind that my solution doesn't account for the full set of equations, the results are quite similar indeed, apart from a normalization factor.


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