Resolving the Wolf–Rayet Mass Discrepancy with the Photogravitational Parameter Φ

This work presents the photogravitational parameter Φ ≡ L/(Mg) as a surface-based, model-independent diagnostic for Wolf–Rayet stars. The method is calibrated on 12 WR+O binaries, achieving ~9% RMS accuracy, and applied to an extended dataset of 10 isolated WR stars. The results consistently show systematic mass discrepancies of 35–54% compared to evolutionary tracks, with a median offset of ~42.5%. The framework includes full calibration values, error budgets, and a GR closure test (δ_GR), providing a falsifiable and reproducible approach to WR mass determinations. These findings have direct implications for mass-loss prescriptions, envelope physics near the Eddington limit, binary evolution pathways, and the final masses of supernova and black hole progenitors. The method scales to the full Galactic WR population of ~600 stars.