3D position sensing on UltraPeRL CdZnTe detectors
Experimental results of depth and lateral position sensing on UltraPeRL pixellated CdZnTe detectors using signal ratios are presented. Each detector employs one CdZnTe crystal of 20 mm times 20 mm times 5 mm with 8 times 8 pixel electrodes fabricated on the anode surface. The anode pixel pitch is 2.4 mm. The signal ratios are calculated using the signals induced on the collecting pixel and the eight neighboring pixels. The signal on each collecting pixel is then corrected for depth of interaction using the signal ratios. We obtained 7.6%, 4.2% and 2.5% FWHM energy resolution at 122 keV, 356 keV and 662 keV, respectively.
Event classification in 3D position sensitive semiconductor detectors
A set of analytical methods for pixelated 3D position sensitive semiconductor detectors has been developed to make better measurements of gamma-rays in the 30 keV to 3 MeV energy range. The ability to classify pixel charge sharing, x-ray escape, pair production, and Compton scattering allows for more accurate and efficient energy reconstruction and Compton imaging routines. The techniques are based on the analysis of digitized preamplifier waveforms from the electrodes that sense charge following an interaction. Accurate identification of an event is based on the comparison of an expected detector response with precise measurements of an interaction’s resulting signal amplitude, shape, and timing characteristics. A tungsten collimator is used to demonstrate the accuracy of the classification methods. Experimental results taken with large volume CZT and HgI2 detectors are compared with system simulations.
THE RELIGIOUS SITES DURING THE CHINESE CULTURAL REVOLUTION, 1966-1976
This study presents a thought-provoking picture of statistical data regarding the growth patterns of the religious sites for five main Chinese religions during the Cultural Revolution from 1966 to 1976. Applying comparative and quantitative lenses, this paper addresses the diE™erent growth rates of religious sites during the four diE™erent periods from 1949 to 2004 to test the relative growth pace of religious sites during the Cultural Revolution. To understand the patterns of growing religious sites from 1966 to 1976, this study also compares the diE™erent growth rates of religious sites between the first phase (1966 to 1970) and the second phase (1971-1976) of the Cultural Revolution. Furthermore, it provides detailed information concerning the year of building new religious sites for all five major religions that hold more than 2,500 new religious sites during the Cultural Revolution. In addition, the study shows the top five provinces which built the most new religious sites while denoting their respective rural and urban locations in an eE™ort to demonstrate their geographical expansion during the period. Finally, this study addresses the growth rates of the national population and per capita GDP as compared to the growth of the religious sites during the period of national disaster (1966-1976).