<tt>XSNAP</tt> : An X-Ray Supernova Analysis Pipeline with Application to the Type II Supernova 2024ggi

Abstract X-ray observations of Type II supernovae (SNe II) probe the physics of SN shocks and the mass-loss histories of their progenitor stars. We present multiepoch, X-ray observations of SN II 2024ggi ( D ≈ 7.2 Mpc) from Swift-X-ray Telescope, Chandra X-ray Observatory, and XMM-Newton, which cover ∼1–344 days since first light. We analyze these observations using a new open-source Python package called XSNAP , which standardizes a unified command-line interface for instrument-specific reduction and spectral extraction. XSNAP introduces application programming interfaces for per-epoch spectral modeling through PyXspec and emcee Markov Chain Monte Carlo fitting. We employ XSNAP to model the multiepoch X-ray spectra of SN 2024ggi with an absorbed thermal bremsstrahlung model and calculate a steady progenitor mass-loss rate of (6.2 ± 0.2) × 10 −5 M ⊙ yr −1 ( v wind = 20 km s −1 ), for which the detected X-ray emission traces the final ∼117 yr before explosion. The software is publicly available on GitHub, with a released package on the Python Package Index (PyPI).