- Add EULER_GAMMA, ME_KEV, R0_FM to constants.py - Replace hardcoded 0.511, 0.5772..., 1.2 with imports from constants - Fix T_to_W parameter name: T_kev -> T_MeV (it takes MeV, not keV) - Remove duplicate ME_ME from spectrum.py (import ME_MEV from constants) - Remove hardcoded r_0 from detector_response.py and radiative.py - Update CONVENTIONS.md to reference correct constant names