Code and data for: Study of the up-down asymmetry in $B^+\to K^+\pi^+\pi^-\gamma$ using $K_1(1270)$ amplitudes constrained by semileptonic $D$ Decays

This record contains the code and supporting files for the study “Study of the up-down asymmetry in $B^+\to K^+\pi^+\pi^-\gamma$ using $K_1(1270)$ amplitudes constrained by semileptonic $D$ decays.” The calculations evaluate the intensity-averaged hadronic factor $\bar{\mathcal H}_{ud}$ for four $K_1(1270)$ amplitude models and explore the effect of a $K_1(1400)$ contribution. The archive includes the fitted parameter files and covariance matrices; ROOT/C++ code for phase-space integration, interference decomposition, mass and Dalitz plots, and the $K_1(1400)$ scan; Python scripts for generating the LaTeX tables; and the resulting text summaries, tables, and PDF figures. The model identifiers are 023 (nominal), 0123 (additional $\rho K$ $D$-wave), 0234 (additional $(K\pi)$ $S$-wave component), and 0235 (additional $\omega K$ $S$-wave). To regenerate the results, install ROOT and Python 3, then run sh refresh_all.sh from the archive directory. The script generates the intermediate ROOT files; these large files are not included in the archive.