Reproducible Python Implementation of an SCS–Hill–Wheeler Statistical Model for Nuclear Fission Charge Yields (ENDF/B-VIII.0)

This Zenodo deposit provides a reproducible Python codebase for computing and fitting fission-product charge-yield distributions Y(Z) using a statistical framework combining the Selective Channel Scission (SCS) model with Hill–Wheeler (logistic) barrier penetrability.

The workflow supports incident neutron-energy conditions: thermal, 500 keV, and 14 MeV (thermal cases are skipped where not applicable in the provided Y(Z) tables). Jupyter notebooks are included to run the workflow end-to-end.

**Contents**
(1) Python implementation (src/)  
(2) Case definitions in YAML/JSON (cases/; e.g., cases_endfb8_0_fit_ex.yaml)  
(3) Jupyter notebooks (notebooks/; e.g., run_all_9nuclides_with_fermi.ipynb)  
(4) Preprocessed Y(Z) tables derived from ENDF/B-VIII.0 (data/yz/)  
(5) Atomic-mass table in AME2020 `mass.mas20` format (data/mass/)  
(6) Documentation PDFs (README.pdf, and a notebook-run guide)

**Typical outputs**
Results are written under results/endfb8_0/, including per-case CSV files (results/endfb8_0/<nuclide>/<energy>/), charge-yield comparison figures, Reff(Z) point plots (no smoothing curves), and Ex(Z) overlays.

**Quick start**
Create a virtual environment, install requirements, and run Jupyter Lab:
```bash
python -m venv .venv
# Windows (PowerShell): .venv\Scripts\Activate.ps1
# macOS/Linux: source .venv/bin/activate
python -m pip install -U pip
pip install -r requirements.txt
pip install jupyter
jupyter lab