Track reconstruction based on Hough-transform for nTPC

A GEM-TPC prototype, which will be used as a fast neutron spectrometer based on the recoil proton method, is designed and being constructed in Tsinghua University. In order to derive the recoil angle of the recoil proton, tracks of recoil proton in the TPC sensitive volume must be reconstructed. An algorithm based on Houghtransform for track finding and least square method for track fitting was developed in this paper. Based on the Monte Carlo simulation data given by Geant 4, a detailed track reconstruction process was introduced and the spectrum of induced fast neutron was derived here. The results show that the algorithm was effective and high-performance.With the recoil angle of the proton less than 30°, a 4.4% FWHM neutron energy resolution was derived for 5 Me V induced fast neutron, and the detection efficiency was about 2×10-4.