A digital coincidence measurement system using FPGA techniques

作者：Zhu Feng ming; Hsieh S C; Yen W W; Chou H P^*

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2011, 652(1): 454-457.

DOI：10.1016/j.nima.2011.01.150

• Nuclear radiation measurement
• Nal digital spectrometer
• Gamma-gamma coincidence
• Field programmable gate array

A field programmable gate array (FPGA) based digital coincidence system has been developed to use with Nal scintillators for field applications. The analog output signal from the photomultiplier anode is directly transferred into digital signals by pulse height for pulse width conversion. The digital signal contains the energy and timing information of the radiation events. The pulse width is then measured by a vernier type of time-to-digital converter (TDC). The timing information of radiation events is recorded and analyzed by a coincidence unit. Both the TDC unit and the coincidence unit are implemented using a commercial available FPGA board. The measured data is then sent to a personal computer for spectrum display. Efficiency as well as energy calibration has been performed. The system showed a timing resolution about 13 ns and an energy resolution of 12% for 0.511 MeV annihilation gammas; it also successfully demonstrated the background rejection ability through coincidence measurement.

• 出版日期2011-10-1
• 单位清华大学