摘要详情

ID / 提交时间

89 / 2024-09-06 21:41:03

标题

A CERAMIC-GEM NEUTRON DETECTOR WITH A LARGE FIELD OF VIEW FOR ENERGY-RESOLVED NEUTRON IMAGING

关键字

Ceramic GEM, Neutron imaging, Large field of view

主题及专题

TRACK 4: MODELING & SIMULATION

状态

摘要录用

作者

chaoyue zhang / Harbin Engineering University；Institute of High Energy Physics, Chinese Academy of Sciences；Spallation Neutron Source Science Center

Jianrong Zhou / University of Chinese Academy of Sciences；Institute of High Energy Physics, Chinese Academy of Sciences；Spallation Neutron Source Science Center

Yushou Song / Harbin Engineering University

Lin Zhu / University of Chinese Academy of Sciences；Institute of High Energy Physics, Chinese Academy of Sciences；Spallation Neutron Source Science Center

Zhijia Sun / Chinese Academy of Sciences；Institute of High Energy Physics；Spallation Neutron Source Science Center

Xiaojuan Zhou / University of Chinese Academy of Sciences；Institute of high energy physics, Chinese Academy of Sciences；Spallation Neutron Source Science Center

摘要

Energy-resolved neutron imaging is an effective method for studying the internal structure and residual stresses of materials. Different sample sizes have varying requirements in the imaging field of view and spatial resolution of the detector. To meet the practical needs of large field of view and high spatial resolution, a detector was constructed using one ceramic GEM (Gas Electron Multiplier) foil of 200 mm × 200 mm, and it adopted a thinner conversion with 0.1 um thickness ^natB4C material and the stopping layer the with 2.0 μm thickness Al to improve spatial resolution.

To investigate its basic characteristics, several neutron beam tests were carried out at the 20th beamline (BL20) of China Spallation Neutron Source (CSNS). The plateau length of the GEM-based neutron detector was 200V, and the working high voltage of the detector was determined to be -1600V. The wavelength spectrum measured with this detector using the TOF (Time Of Flight) approach at CSNS agreed well with that measured using an LND commercial monitor. The spatial resolution of the detector was below 1.93 ± 0.01 mm (FWHM), and the detector demonstrated excellent energy/wavelength selective neutron imaging capabilities. In addition, the counting rate of the detector fluctuated only 4% (RSD) during different positions.

The results show that the detector is an ideal candidate for beam monitoring and neutron imaging, and it has been applied to the Energy Resolved Neutron Imaging Instrument (ERNI) of the CSNS.