Diffusion lim atmesc change

[mgialluca]

Proposed changes

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Types of changes

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• Bugfix (non-breaking change that fixes an issue)
• [ X] New feature (non-breaking change that adds functionality)
• New module (non-breaking change that adds a new module)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist

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• [X ] I have added tests that prove my fix is effective or that my feature works
• [ X] I have adhered to the Style or run the clang format code shown here
• [X ] I have added necessary documentation (if appropriate)
• I have run Valgrind on new tests to ensure no errors were found
• [ X] (Optional) I have added an example showcasing the new change

Further comments

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[github-actions]

Unit Test Results

14 440 tests  +258   14 440 ✔️ +258   4m 45s ⏱️ +14s
         1 suites ±    0            0 💤 ±    0 
         1 files   ±    0            0 ❌ ±    0 

Results for commit 0fa56b5. ± Comparison against base commit 65a31dc.

♻️ This comment has been updated with latest results.