2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/191629The HARP Collaboration recently published calibrations of their TPC and RPC detectors, and differential cross-sections of large-angle pion production in proton-nucleus collisions. We argue that these calibrations are biased and cross-sections based on them should not be trusted.17 pages, 13 figuresHigh Energy Physics - Experimenttext