[Mesa-users] Gyre's 'GAMMA' boundary condition

[Warrick Ball]

Hi Santiago,

I don't have an immediate answer for you but GYRE is now hosted on GitHub and you may wish to open an issue there:

     https://github.com/rhdtownsend/gyre/issues

It's also worth letting us know which version of GYRE you're running, though from the `build_poly` call I guess it's the latest version (v8.1).

Cheers,
Warrick

___________

Warrick Ball
Senior Research Software Engineer
University of Birmingham
W.H.Ball at bham.ac.uk

On Sat, 11 Oct 2025, Santiago Andres Triana via Mesa-users wrote:

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> Hi all,
> I'm trying to compute the lowest order g modes using gyre of an n=1 polytropic model (generated with --Gamma_1=3.0 using gyre's own build_poly tool).
> I need to set a no penetration boundary condition on the outer boundary, and according to the online documentation, the option 'GAMMA' fits the bill.
> However, such an option is not recognized by gyre. By looking at the source code, the closest matches are options 'GAMMA1' and 'GAMMA2' but can't find much info about them.
> Running gyre using 'GAMMA1' produces an output but the displacement near the outer boundary does not seem to be correct (i.e. the radial derivative of the displacement is not zero there).
> Running gyre with option 'GAMMA2' produces a core dump.
> 
> The command to build the model is:
>  $GYRE_DIR/bin/build_poly --n_poly=1.0 --dz=0.001 --Gamma_1=3.0 poly.n1_gamma3.h5
> 
> Any advice would be much appreciated. Thanks in advance!
> 
> Santiago
> 
> 
>