Speaker
Description
To support cutting-edge research, including high-resolution structural analysis and high-precision stress-strain measurements, the general-purpose powder diffractometer (GPPD) at the China Spallation Neutron Source (CSNS) is in urgent need of an upgrade, with the performance enhancement of scintillator neutron detectors as the core technical strategy. Expanding the effective detection coverage of scintillator detectors and optimizing the detector unit structure can better meet the comprehensive requirements of advanced neutron scattering experiments for detection systems. Correspondingly, the detector upgrade imposes stringent demands on the associated readout electronics, such as higher integration density, improved position resolution, and enhanced large-scale channel processing capability. A dedicated application-specific integrated circuit (ASIC) tailored to the new scintillator detector has been developed, and a multiplexed readout method based on the “ASIC + multiplexer” architecture is proposed and systematically investigated. A compact, highly integrated, and large-scale readout electronics system is realized without sacrificing position resolution. Meanwhile, to adapt to the Apache-Kafka data stream processing platform of CSNS, the back-end electronics are implemented using system-on-chip field-programmable gate array technology, enabling direct communication with the Kafka platform. Neutron beam experiments integrated with the new scintillator detector demonstrate that the system achieves high-quality two-dimensional neutron imaging under 8:1 channel multiplexing, with a neutron detection efficiency exceeding 45% at 2 Å. The overall performance of the system meets the high-precision measurement requirements of the upgraded GPPD spectrometer.