A system of detection and data acquisition for time-of-flight neutron diffraction setups

A simple system of neutron detection and data acquisition is considered. It is composed of sector sets of 3 He counters, timing amplifiers-discriminators, 8-stop time-to-digital converters (TDCs), and a gate duration generator, as well as branch and crate controllers coupled to a computer. The system is used in neutron diffraction setups on the neutron spallation source at the Institute for Nuclear Research. The output pulse from the timing amplifier-discriminator is timed with the fast electron component of an avalanche in the detector. Neutron time-of-flight spectra are formed by a TDC in its embedded memory over the recording enable time ranging from 1 to 63 ms. The TDC time range has 4096 gradations with time step of 0.125–128 μs. Fast data acquisition is ensured by the Linux kernel driver. The data acquisition software based on the Qt4 library recognizes modules in the CAMAC crate and displays spectra with their preliminary processing.