Two-dimensional high precision thermal neutron detector

A position resolution of 1.3 mm (fwhm) and integral non-linearity of ±0..1% is achieved in a two-dimensional 18 × 18 cm2 thermal neutron detector. The gas proportional detector operates at a moderate pressure (5–6 atm) with a 3HeC3H8 mixture and at very low required avalanche gain (∼30) by virtue of the high precision centroid finding position readout.