A few number of neutron detectors with fast response are available regarding neutron energies between 2-20 MeV. The most common detectors for this energy region are plastic scintillators. However, these detectors suffer from gamma sensitivity and also neutron damage. Therefore, generally there is a demand for new fast response neutron detectors with gamma insensitivity and radiation resistant nature. The demand is, in particular, in fusion technology and intense accelerator based neutron sources where a wide dynamic range neutron detector is required.Since neutrons do not directly ionize atoms, detection relies on combination of a neutron to charge particle converter with a charged particle detector. The charged particle detector governs the neutron detector characteristics as well. Among the radiation resistant, fast charged particle detectors, parallel plate avalanche chamber (PPAC) combination with a fast neutron to charged particle converter seems an attractive attempt provided that the light conversion charged particles are efficiently detected in a low pressure thin gap PPAC.In this work, we report on a study based on PHITS computer-simulation code of particles and heavy ions, that evaluated the key parameters of the detector such as, the amount of energy converted into a measurable signal and the detector efficiency. Optimization results of PPAC with a polypropylene converter are presented as well.
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