Absolute particle flux determination in absence of known detector efficiency. The “Influence Method”

In this article we introduce a new method, which we call the “Influence Method”, to be employed in the absolute determination of a particle flux, most especially applicable to time-of-flight spectrum determination of a neutron beam. It yields not only the absolute number of particles but also an estimator of detectors efficiencies. It may be useful when no calibration standards are available. The different estimators are introduced along with some Monte Carlo simulations to further illustrate the method.