.. _diffusion_smoothness:

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diffusion_smoothness
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.. tags:: star, element-diffusion, brunt-profile, low-mass

This test suite case checks that element diffusion produces a sufficiently smooth Brunt profile.

This test case has 2 part2. Click to see a larger view of a plot.

* Part 1 (``inlist_zams``) builds a 1.0 |Msun|, Z=0.02 metallicity, main-sequence model.

* Part 2 (``inlist_diffusion_smoothness``) activates element diffusion and continues the evolution for 3e9 years. The ``run-star_extras.f90`` then checks that the Brunt profile is sufficiently smooth in the central portion of the model.

.. image:: ../../../star/test_suite/diffusion_smoothness/docs/brunt_000036.svg
   :width: 100%

pgstar commands used for the plot:

.. literalinclude:: ../../../star/test_suite/diffusion_smoothness/inlist_diffusion_smoothness
  :language: console
  :start-at: &pgstar
  :end-at: ! end of pgstar namelist

Last-Updated: 06Jun2021 (MESA 5be9e57) by fxt

Last-Run: 12Apr2026 (MESA c79eae5c5) by vincentva on procyon in 121 seconds using 8 threads.