Development of Digital Multi-channel and Time-division Pulse Height Analyzer Based on PXIE Bus for Hard X-ray Diagnostic in East

Abstract

Pulse height analyzer (PHA) is an important component of hard X-ray diagnostic to measure energy spectrum in experimental advanced superconducting tokamak (EAST). In order to satisfy physics research of high parameters plasma, the energy resolution, time resolution and number of channels of PHA are required to be improved. A Multi-channel and time-division PHA (MTPHA) based on PXIe bus is designed using 16 bit ADC and FPGA as core processing unit, and has a maximum number of channel addresses of 4096 and minimum time resolution of 2 ms. The function of energy spectrum analysis is realized in the FPGA. Moreover, the PXIe communication drive is realized by combination of hardware code in FPGA and LabVIEW software in host computer. The MTPHA performance has been tested in the lab with pulse generator, 152Eu isotope radiation source and tested in plasma discharge of EAST. It is found in the lab that the full width at half maxima (FWHM) of MTPHA is no more than 2 channels, and the linear correlation coefficient R of pulse height and channel address is 1. In EAST, the MTPHA can work well and produce experimental data consistent with other diagnostics.