Study Of Nuclear Spectrum Acquisition Based On FPGA Hardware Arithmetic

Through the analysis of nuclear spectrum, we can get ray energy, radiation source activity, and the type of the radiation source. So, nuclear spectrum is the most pivotal data in nuclear physics experiments. With the development of particle physics, nuclear physics and reactor physics, demands on the speed and accuracy of nuclear detection system is getting higher and higher. In recent years, with the rapid development of the ADC technology and the programmable logic device technology, the technology of digital nuclear data acquisition has been rapid development, which provides a new way of thinking to nuclear data processing. In this paper, the FPGA hardware algorithms and high-speed ADC chip and USB transmission module has been used to digitize the nuclear data. The pulse height and area has been obtained in the FPGA, and at the computer get them and transform them into a spectrum with LabVIEW.At first, through theoretical analysis this paper verify the feasibility of obtaining nuclear spectrum data based on nuclear pulse height analysis(PHA) and pulse area analysis(PAA), and PAA proved superior than PHA in weaken the influence of the noise signal. Secondly, this paper has introduces the method of waveform correction, baseline recovery, PAA and PHA. In addition, this paper has explained the hardware and the connection between hardware which used in the nuclear data acquisition system. And, the program development of FPGA and software design of USB module and LabVIEW has been explained in detail. At last, the nuclear data acquisition experimental platform has been build. Base on the experimental platform get and analysis the data get with PHA and PAA, and compare to the data get with MCA8000 D.Through theoretical analysis and experimental data analysis, this paper verifies the feasibility of nuclear spectrum acquisition base on PAA and PHA, and verifies the PAA can weaken the influence of the noise signal and improve the energy resolution.