A prototype of the linear position-sensitive detectors for CPHS

The time-of-flight (TOF) small-angle neutron scattering (SANS) di_ractometer is one of the first instruments to be built at the Compact Pulsed Hadron Source (CPHS) of Tsinghua University. It requires a 1 × 1 m2 area detector to cover the designed Q-range without moving the detector. We contemplate an array of 1D linear position-sensitive detectors (LPSDs) of 3He gas proportional counters. Each LPSD will have a cylindrical geometry with an active length of 1 m and a diameter of 12 mm. We describe the in-house fabrication of the first LPSDs and the preliminary testing of their performance.