Rossi-alpha neutron experiments are used to estimate the prompt neutron decay constant of
a fissile assembly, a quantity of widespread interest in applications including in nuclear
nonproliferation and criticality safety. This work develops a mathematical model to efficiently
estimate measurement uncertainty of Rossi-alpha neutron experiments inferred from a two-
exponential fit model with histogram binning. The derived uncertainty estimates were
validated using repeated Rossi-alpha measurements of a subcritical, 4.5-kg sphere of …