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Screening Method Approaches for NSE compatibility

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Active
Tech stack
cpp
Domain
backend

Research direction

Start with the attached detailed-balance-screening_approaches_annotated.pdf and the related issue #767. Compare the proposed symmetric-screening and sequential-proton-capture approaches, then inspect the repository's NSE and screening entry points to determine the affected implementation area. Done requires an agreed approach for supporting general screening methods with physically consistent detailed balance.

Written by the indexing model from the issue text.

Description

We currently limit ourselves with using Chabrier&Potekhin1998 screening and these only includes classical screening portion.
This was desired since the derived rate can be represented in the unscreened representation and apply the screening routine
just like how you would normally apply the screening routine (This is approach 2 described in the attached note).
Sometimes we might want to include quantum correction terms, or any generic screening routines. A related issue is in https://github.com/pynucastro/pynucastro/issues/767.

Right now the easiest way is likely to revive the idea of symmetric screening.

  1. Only allow the quantum portion to be symmetric. If the routine to compute it only depends on the reactant, we still have an unphysical issue where the quantum screening factor for the derived rate then depends on its products. see appendix in https://iopscience.iop.org/article/10.1086/510709
  2. We figure out a way to compute it such that the quantum factor depends on both reactants and products which makes it physically reasonable that the quantum portion is symmetric. This is discussed in https://iopscience.iop.org/article/10.1088/1742-6596/1787/1/012047/meta and https://academic.oup.com/mnras/article/486/1/449/5423884 .
  3. Consider sequential proton capture approach to compute $\mu^C$ using any general sceening routine -- see approach 5 (also see winnet paper https://arxiv.org/abs/2305.07048) in attached note.
  4. Use full symmetric screening and arbitrary method to compute $\mu^C$. Least physically consistent approach since different routines are used but most flexibility?

Attached note:
detailed-balance-screening-approaches_annotated.pdf

Dominant language
C++
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Forks
47
Avg merge
3d 7h
Merged PRs (30d)
10

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