A Two-Dimensional Position-Sensitive Detector for Thermal Neutrons

We have developed and tested a thermal neutron, two-dimensional position-sensitive detector for use in neutron scattering from biological samples. The detector is based on a multi-wire proportional concept with a gas filling of 6 atmos. He3, 4 atmos. A, and 0.5 atmos. CO2. The position readout uses a resistive wire with charge division to determine position. We have measured a resolution of less than 3 mm (EWHM) with a detection efficiency of 70% at 2.8 Å neutrons. Considerations leading to an optimal configuration are discussed.