Light output response of the LVD liquid scintillator to neutron-induced nuclear recoils

TL;DR

This study measures the light output response of the LVD liquid scintillator to neutron-induced nuclear recoils in the 4-11 MeV range, using experimental data and Monte Carlo simulations to determine quenching factors.

Contribution

It provides the first detailed measurement of the scintillator's response to neutron recoils in this energy range, validated by Monte Carlo simulations and modeled with Birks' law.

Findings

Light output response is well described by Birks' model.

Quenching factors are consistent with previous studies on similar scintillators.

Results enable improved neutron spectroscopy using the LVD detector.

Abstract

The organic liquid scintillator used in the LVD experiment (INFN Gran Sasso National Laboratory) has been exposed to an Am-Be neutron source to measure the light response function for neutron energies in the region from about 4 to 11 MeV. A full Monte Carlo simulation, incorporating the detector response, is used to generate neutron scattering spectra which are matched to the observed ones to determine the quenching factors. The obtained light output response is well described by the semi-empirical Birks model. The results, consistent with those obtained by other authors using similar hydrocarbonate scintillators, can be of interest for fast and high-energy neutron spectroscopy that could be performed with this detector.