A Correlated Pulse Generator for Thermal Neutron Coincidence and Multiplicity Counting Applications

Year
2006
Author(s)
S.C Bourret - Los Alamos National Laboratory
M. Newell - Los Alamos National Laboratory
M.R. Sweet - Los Alamos National Laboratory
W. Geist - Los Alamos National Laboratory
M. S. Krick - Los Alamos National Laboratory
W. Hansen - Los Alamos National Laboratory
S. C. Bourrett - Los Alamos National laboratory
Abstract
A neutron pulse simulator (NPS) has been developed for use as a training and testing tool for neutron coincidence and multiplicity counting systems. Commercially available pulse generators are not capable of generating multiplicity distributions that accurately simulate neutron pulse streams produced from radioactive material. The NPS generates pulses that are correlated in time-giving pulse streams that resemble those created from an actual neutron measurement instrument. The NPS can produce arbitrary singles, doubles and triples rates up to a total count rate of 1 MHz. The unit provides a convenient and easy to use source of simulated neutron pulses for measurement control, quality control, diagnostics, and training for neutron coincidence counting systems. The instrument is a modernization of an old ISA bus-based correlated pulser. The new pulser is 5 times faster, implements a PCI bus interface to a built-in computer, and has a modern Windows-based user interface. The user interface is used to set multiple operating modes including random pulses, periodic pulses, pulse pairs, and correlated pulses in different simulation modes.