COSI gamma-ray detectability of i-process isotopes — data and analysis code

This package contains the data and analysis code required to reproduce Figures 1–4 of the manuscript Herwig, Denissenkov & Burns (2026), "Can COSI detect γ-ray lines from rare isotopes produced in the astrophysical intermediate neutron-capture process?", submitted to Physical Review Letters (rev. requested).

Contents: README.md, CITATION.cff, data/ (predicted γ-ray photon fluxes from MPPNP post-processing for four RAWD i-process models A–D and a post-AGB VLTP "Sakurai" model at reference distance d_ref = 3000 pc), analysis/ (Python scripts that reproduce all figures), and figures/ (the seven PDF panels appearing in the paper as Figs. 1–4).

Method: For every (model, isotope, distance) we compute the time-averaged photon flux ⟨F⟩_T = (F0 τ / T)[1 − exp(−T/τ)] and compare it to the COSI narrow-line sensitivity S(E_line, T) for T = 1 yr (obtained from the 2-yr requirements curve by the background-limited scaling S(T) ∝ T^−1/2). See Sec. III of the manuscript for full discussion.

Reproducibility: Python 3.10+ with numpy, matplotlib, and scipy. Run `python analysis/make_figs_1_2.py` for Figs. 1–2 and `python analysis/make_visualizations.py` for Figs. 3–4. See README.md for full details.

Licensing: code (*.py) is released under MIT; data (data/*.txt) under CC BY 4.0.