An exact solution for a non-extending dead time problem in passive neutron assay

The Markov Chain method is used to obtain an exact solution to the problem of deriving the count rate, for time correlated pulses arising in passive neutron assay, in the presence of a non-extending dead time. While the discussion presented in the main text assumes only singlets and doublets in the pulse train, extension to include higher multiplicities is described in the Appendix.