The Preliminary Realize Of Instrument For Radionuclide Identification By Detecting Gamma Ray

With the development of nuclear energy and nuclear technology,management of using source in areas of nuclear energy,industry and medical science is imperfect.As well as meet the need for nuclear terrorism,instrument for radionuclide identification was born.It isaninstrument for identifying radionuclide by comparing “fingerprint”of measured radionuclide and nuclide library. The purpose of this study is to design a set of digital radionuclide identification instrument hardware and software platform.The whole hardware design has a detector of LaBa3, key devices of FPGA and AD9215, circuit control kernel of single chip microcomputer CY7C68015 A.It introduces the thought of design and circuit principle of programmable amplifier circuit, analog-to-digital conversion circuit and USB communication circuit in detail.Parameter selection problem of digital trapezoidal shaping has been emphatically discussed. Method of selecting parameter is given forsupporting the design of digital gamma spectrometer. Finally, the parameters of designed hardware are analyzed.Its energy resolution is 3.30%. In the algorithm of radionuclide identification, accuracy of the algorithm for seeking peak is of great importance. According to the optimal theory of calculating peak widthof sterlinski peak area method, this studyhave designed method ofoptimal discriminant of peak width for seeking peaks.But this method quite depends on the algorithm of removing background.Therefore, this study have designed a kind ofcutting technology to remove background of full spectrum by automatic fitting the pattern of peak.After testing by seeking peaks in the IAEA standard spectrum and the measured spectrum, algorithm this study designed has more powerful abilities of seeking peaks compared with GammaVision 32 and Genie2000.Finally,in the platform of Visual Studio 2013,I completed the writing of software for radionuclide identification. Aftersome testing, I find that instrument for radionuclide identification designed by this study can well distinguish 1 or 2 or 3 or 4 kinds of radionuclides which has emission of gamma particle.