A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers

摘要

A new method for measuring chance-coincidence backgrounds during thecollection of coincidence data is presented. The method relies on acquiringdata with near-zero dead time, which is now realistic due to the increasingdeployment of flash electronic-digitizer (waveform digitizer) techniques. Anexperiment designed to use this new method is capable of acquiring morecoincidence data, and a much reduced statistical fluctuation of the measuredbackground. A statistical analysis is presented, and used to derive a figure ofmerit for the new method. Factors of four improvement over other analyses arerealistic. The technique is illustrated with preliminary data taken as part ofa program to make new measurements of the prompt fission neutron spectra at LosAlamos Neutron Science Center. It is expected that the these measurements willoccur in a regime where the maximum figure of merit will be exploited.