Prototyping a 2m x 0.5m MRPC-based neutron TOF-wall with steel converter plates

A 2m x 0.5m large prototype of an MRPC-based (Multi-gap Resistive Plate Chamber) neutron Time-Of-Flight-wall for detecting relativistic neutrons in an energy range from 200MeV to 1 GeV was successfully designed and realized. It consists of steel plates which convert neutrons via hadronic interactions into charged particles, followed by a 2x2 gap MRPC-structure to detect the charged particles. Tests were carried out using 30MeV electrons with an energy close to the minimum of ionization in order to study the properties of the prototype achieving an efficiency larger than 90% and a time resolution better than 100 ps. For units with an active area of 40 cm x 20 cm and otherwise the same design, quasi-monochromatic neutrons with a peak energy of 175MeV were utilized to study their response to relativistic neutrons. Detailed montecarlo simulations were performed both for the small and for the large modules to simulate their properties to both neutrons and electrons and to study the performance of the final neutron detector assembly with an area of 2m x 2m for single-neutron and multi-neutron events.