[mesa-users] Diffusion of Heavy elements (Instability in some evolution tracks)

[Nsamba Benard]

Greetings to You all,

I am making a grid of models with diffusion included using mesa-r7624. In
some of my models, the evolution track has some instabilities (fast
variation in temperature and luminosity) as shown in the attached plot.

However, when I consider diffusion of only Hydrogen and Helium, the model
track is good (plot attached).

I would like to know what is causing this instability when diffusion of
heavier elements is included (this happens to some models)? Any suggestions
on how to fix this problem? I have also attached my inlists.

Thank you.

Cheers,
Benard


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Benard Nsamba
PhD student                                  Centro de Astrofisica
                                                    Universidade do Porto
                                                    Rua das Estrelas
Tel: +351 920 404 108                   4150-762 Porto, Portugal
E-mail: benard.nsamba at astro.up.pt <Benard.Nsamba at astro.up.pt>
Skype: benardnsamba
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