Calculation of the Geometric Factor in a New Experiment Aimed at Studying Radiative Neutron Decay

Abstract

A new experiment aimed at studying radiative neutron decay is proposed. The respective experimental procedure reduces to measuring the time spectra of triple coincidences of the emitted photon, beta electron, and recoil proton along with the spectrum of double coincidences of ordinary decay products. By means of this procedure, we were able to measure for the first time the branching ratio for radiative neutron decay, BR = (3.2 ± 1.6) × 10⁻³ (at a confidence level of C.L. = 99.7%, the photon energy being in excess of 35 keV) in 2005 at our old setup. The average value of this branching ratio was greater by a factor of 1.5 than its theoretical counterpart calculated on the basis of the Standard Model. However, we cannot state that we have seen a deviation fromthe StandardModel prediction since the experimental error was quite large in that experiment. The present study is devoted to implementing, by means of the popular Geant4 code package, a computer analog of the respective experiment at a new facility. Our calculations reveal that the resulting geometri©factor values make it possible to a accumulate, in a live experiment, a data sample sufficient for measuring the above branching ratio to a precision of a few percent.