Development Of Readout Electronics For BNCT Neutron Detectors

Boron neutron capture therapy(BNCT),as an advanced cancer treatment method in the world,shows broad prospects.This treatment method requires accurate control of neutron flux to kill cancer cells,so matching neutron detectors are required to obtain accurate neutron flux distribution data.Currently,a boron neutron cancer terminal detector that has been applied in practice is the Gas Electron Multiplier(GEM)coated with boron.The detector is a micro structured gas detector(MPGD)with good spatial resolution,which can meet the requirements of large area detection with high event rates.Accordingly,it puts forward requirements for readout electronics such as multi-channel and low noise.Therefore,it is necessary to develop a matching readout electronics system.Based on the diverse requirements of various gas detectors,various dedicated integrated chips(ASIC)have been developed at home and abroad,and supporting readout electronics systems have been designed to adapt to different targets and specifications of gas detectors.However,due to the different indicators of different ASIC chips,designing a readout electronics system for boron neutron terminal detectors requires understanding the output characteristics of the detector and investigating various characteristics of different ASIC chips,selecting appropriate ASIC chips,and designing matching subsequent electronics modules.This paper investigates various types of ASIC chips that are relatively mature in design and application in the world at present.Based on performance comparison and practical requirements,AGET chips are selected as the main chip of the BNCT neutron detector readout electronics system,and a matching electronics front-end board is designed to process the detector output signals;According to the interface and data requirements,the appropriate development board is selected and the chip configuration program and data processing program are developed,which are sent to the host computer.Based on the above design,the hardware design related to readout electronics for the BNCT neutron detector has been completed,and electronic performance testing has been conducted.The electronic testing results show that the front-end readout electronics developed based on the AGET chip in this article can meet the bipolar signal processing of 64 channels in the dynamic range of 120 f C~10p C at a sampling frequency of 1~100MHz.The front-end board noise is less than 6000e-,and the integral nonlinearity is less than 2%,which can meet the various requirements of BNCT neutron detectors.At the end of this article,the related work on the development of front-end electronics based on AGET chips and the shortcomings in the design are summarized,in order to prepare for the subsequent improvement work.