Investigation of gamma-ray sensitivity of neutron detectors based on thin converter films

TL;DR

This paper evaluates the gamma-ray sensitivity of neutron detectors using thin converter films, demonstrating comparable gamma rejection to traditional 3He detectors, and applicable to various converter materials.

Contribution

It provides a comparative analysis of gamma-ray rejection in thin film neutron detectors versus 3He detectors, including experimental validation and simulation results.

Findings

Thin film neutron detectors achieve gamma-ray rejection similar to 3He detectors.

Simulation results align with experimental measurements.

Applicable to various converter materials like 6Li and 10BF3.

Abstract

Currently, many detector technologies for thermal neutron detection are in development in order to lower the demand for the rare 3He gas. Gas detectors with solid thin film neutron converters readout by gas proportional counter method have been proposed as an appropriate choice for applications where large area coverage is necessary. In this paper, we investigate the probability for gamma-rays to generate a false count in a neutron measurement. Simulated results are compared to measurement with a 10B thin film prototype and a 3He detector. It is demonstrated that equal gamma-ray rejection to that of 3He tubes is achieved with the new technology. The arguments and results presented here are also applicable to gas detectors with converters other than solid 10B layers, such as 6Li layers and 10BF3 gas.