Neutron detector

Detection of neutrons is among the standard techniques in conventional studies of $\mu$CF, since they easily exit from the target containers which typically consist of thick walls.

Detectors using the liquid scintillator NE213 were used with pulse shape discrimination (PSD) provided by hardware modules (Link System PSD-5010 and PSD-5020). Taking advantage of the difference in the liquid scintillator light output time-structure between neutrons and gammas, the PSD module could discriminate the two at the trigger level.

The electronics diagram for neutron detection is given in Fig. 3.23. A pair of plastic scintillators placed in front of the detector was used in anti-coincidence to reject charged particles. Together with neutron triggers, gammas were recorded but were pre-scaled by a factor of 30.

  

Figure 3.23: Electronics diagram for a neutron detector. Charged particle anti-coincidence was required for the neutron/gamma detection. The pulse shape discriminator LINK 5010 (5020 for the second detector) provided a trigger level discrimination of neutrons from gammas, though the latter were also recorded, pre-scaled by factor of 30. For the sub-trigger N1TRG to fire, the event has be in coincidence with EVG.