A novel energy resolved neutron imaging detector based on TPX3Cam for the CSNS

TL;DR

This paper presents a new neutron imaging detector prototype based on TPX3Cam that achieves high spatial and timing resolution, enabling energy-resolved neutron imaging suitable for CSNS applications.

Contribution

The study develops and evaluates a novel energy-resolved neutron imaging detector using TPX3Cam, demonstrating its capability for high-resolution spatial and spectral neutron imaging.

Findings

Achieved 57 μm spatial resolution with centroiding algorithm.

Timing resolution on the microsecond scale.

Wavelength spectrum matched beam monitor measurements.

Abstract

The China Spallation Neutron Source (CSNS) operates in pulsed mode and has a high neutron flux. This provides opportunities for energy resolved neutron imaging by using the TOF (Time Of Flight) approach. An Energy resolved neutron imaging instrument (ERNI) is being built at the CSNS but significant challenges for the detector persist because it simultaneously requires a spatial resolution of less than 100 {\mu}m, as well as a microsecond-scale timing resolution. This study constructs a prototype of an energy resolved neutron imaging detector based on the fast optical camera, TPX3Cam coupled with an image intensifier. To evaluate its performance, a series of proof of principle experiments were performed in the BL20 at the CSNS to measure the spatial resolution and the neutron wavelength spectrum, and perform neutron imaging with sliced wavelengths and Bragg edge imaging of the steel sample. A spatial resolution of 57 {\mu}m was obtained for neutron imaging by using the centroiding algorithm, the timing resolution was on the microsecond scale and the measured wavelength spectrum was identical to that measured by a beam monitor. In addition, any wavelengths can be selected for the neutron imaging of the given object, and the detector can be used for Bragg edge imaging. The results show that our detector has good performances and can satisfy the requirements of ERNI for detectors at the CSNS