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Model 42-38

The Ludlum Model 42-38 WENDI-2 (Wide Energy Neutron Detection Instrument) Neutron Detector is designed for detection of thermal and fast neutrons (0.025 eV to approximately 5 GeV). The neutrons are not directly detected, but through nuclear reactions, which result in energetic charged particles such as protons and tritons. In many instances, intense fields of gamma rays are also found with neutrons. Therefore, it is important to choose a method of neutron detection with the ability to discriminate against these gamma rays in the detection process.

A common reaction for the conversion of slow neutrons into directly detectable particles is n + 3He → 3H + 1H + 0.764 MeV. The Ludlum Model 42-38 WENDI-2 utilizes this reaction in the form of helium-3 (3He), which fills the gas proportional tube of the detector.

This detector is typically used with area monitors, such as Ludlum Models 375, 3276, and 177-61. It can also be used with with portable survey meters.

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