The Design and Development of the Next Generation Neutron Coincident and Low Current Measurement Instruments for Safeguards Applications

Los Alamos National Laboratory (LANL), with support from the Office of International Nuclear Safeguards (NA-241), is developing two new safeguards data acquisition instruments for neutron coincidence counting and low current gamma radiation measurements. Both of these instruments are designed to be simple, inexpensive and robust. The low current measurement instrument incorporates the proven front-end low current amplifier circuitry used in the International Atomic Energy Agency (IAEA) MiniGRAND electronics with the addition of a simple high voltage supply and commercial processor. The neutron coincidence counting instrument uses the coincidence and multiplicity designs developed for the IAEA JSR-15 handheld device and incorporates the same simple commercial processor as the low current measurement instrument. Both instruments have an Ethernet interface as well as a serial-overUSB interface for compatibility with existing IAEA software packages. Both designs are mounted in a small, lightweight chassis and have a similar look and feel. These instruments are compatible with the IAEA’s Real-time and Integrated Stream-Oriented Remote Monitoring (RAINSTORM) interface. RAINSTORM compatibility provides standardized data transfer and data security and a uniform user interface. The successful development of these instruments provides the IAEA with a pair of related instruments replacing obsolete instruments such as the Advanced Multiplicity Shift Register (AMSR) and the MiniGRAND. Advantages of the new instruments are the use of readily available components, simple designs that lead to robust systems, the use of a commercial processor board and an Ethernet interface for new modern installations.