Absolute Proton Detection Efficiency

Many neutron lifetime experiments have been performed following one of two methods, the storage method and the beam method. Currently there is approximately a 4σ, or 8 second, discrepancy between the measured lifetimes of the two methods. The Sussex-ILL-NIST beam method measures neutron lifetime by detecting protons released from decaying neutrons. Absolute proton detection is essential to the beam experimental approach. The absolute detector efficiency is not currently known for existing experiments and could be a source of a hidden systematic error. The proposed calibration technique seeks to determine absolute detector efficiency and can also be used to calibrate new particle detectors for use in future experiments. The method as well as the results of recent Geant simulations will be presented.