Energy calibration of EJ-301 scintillation detector using unfolding methods for fast neutron measurement

We simulated a 2 '' x 2 '' EJ-301 organic liquid scintillation detector in the GEANT4 framework to obtain its response to standard gamma and neutron sources. The resolution scale and Birks' constant for the EJ-301 scintillator have been estimated by comparing the simulation with experimental data. We calibrated the detector for fast neutron measurements with the help of an Am-Be source using two unfolding methods: RooUnfold and Gravel unfold. The neutron spectra obtained from both unfolding methods are similar to the Am-Be ISO (International Organization for Standardization) spectrum. The calibrated detector can be used in an underground site to understand the neutron background in rare event search experiments.