A semi-empirical detector response function(DRF)model is established to fit characteristic X-ray peaks recorded in Si-PIN spectra,which is mainly composed of four components:a truncated step function,a Gaussian-shaped...A semi-empirical detector response function(DRF)model is established to fit characteristic X-ray peaks recorded in Si-PIN spectra,which is mainly composed of four components:a truncated step function,a Gaussian-shaped full-energy peak,a Gaussian-shaped Si escape peak and an exponential tail.A simple but useful statistical distribution-based analytic method(SDA)is proposed to achieve accurate values of standard deviation for characteristic X-ray peaks.And the values of the model parameters except for the standard deviation are obtained by weighted least-squares fitting of the pulse-height spectra from a number of pure-element samples.A Monte Carlo model is also established to simulate the X-ray measurement setup.The simulated flux spectrum can be transformed by Si-PIN detector response function to real pulse height spectrum as studied in this work.Finally,the fitting result for a copper alloy sample was compared with experimental spectra,and the validity of the present method was demonstrated.展开更多
The experiment of this paper is the thermal test of the leakage current of silicon PIN detector. Raising temperature may cause the detector to increase leakage current, decrease depletion and increase noise. Three sam...The experiment of this paper is the thermal test of the leakage current of silicon PIN detector. Raising temperature may cause the detector to increase leakage current, decrease depletion and increase noise. Three samples are used in the experiment. One （called △E） is the sample of 100 μm in thickness. The other two （called E1 and E2） are stacks of five detectors of 1000 μm in thickness. All of them are 12 mm in diameter. The experiment has been done for 21 hours and with power on continuously. The samples have undergone more than 60 ℃ for about one hour. They are not degenerated when back to the room temperature. The depletion rate is temperature and bias voltage related. With the circuit of the experiment and temperature at 35 ℃, △E is still depleted while E1 and E2 are 94.9% and 99.7% depleted respectively. The noises of the samples can be derived from the values at room temperature and the thermal dependence of the leakage currents. With the addition of the noise of the pre-amplifier, the noises of E1, E2 and △E at 24 ℃ are 16.4, 16.3, and 10.5 keV （FWHM） respectively while at 35 ℃ are about 33.6, 33.1, and 20.6 keV （FWHM） respectively.展开更多
基金Supported by National Natural Science Foundation of China(Nos.40974065 and 41025015)Scientific and Technological Innovative Team in Sichuan Province(No.2011JTD0013)"863"Program of China(No.2012AA063501)
文摘A semi-empirical detector response function(DRF)model is established to fit characteristic X-ray peaks recorded in Si-PIN spectra,which is mainly composed of four components:a truncated step function,a Gaussian-shaped full-energy peak,a Gaussian-shaped Si escape peak and an exponential tail.A simple but useful statistical distribution-based analytic method(SDA)is proposed to achieve accurate values of standard deviation for characteristic X-ray peaks.And the values of the model parameters except for the standard deviation are obtained by weighted least-squares fitting of the pulse-height spectra from a number of pure-element samples.A Monte Carlo model is also established to simulate the X-ray measurement setup.The simulated flux spectrum can be transformed by Si-PIN detector response function to real pulse height spectrum as studied in this work.Finally,the fitting result for a copper alloy sample was compared with experimental spectra,and the validity of the present method was demonstrated.
基金National Natural Science Foundation of China (40774095)Co-constructing Foundation of Beijing Municipal Commission of Education (XK100010404)
文摘The experiment of this paper is the thermal test of the leakage current of silicon PIN detector. Raising temperature may cause the detector to increase leakage current, decrease depletion and increase noise. Three samples are used in the experiment. One （called △E） is the sample of 100 μm in thickness. The other two （called E1 and E2） are stacks of five detectors of 1000 μm in thickness. All of them are 12 mm in diameter. The experiment has been done for 21 hours and with power on continuously. The samples have undergone more than 60 ℃ for about one hour. They are not degenerated when back to the room temperature. The depletion rate is temperature and bias voltage related. With the circuit of the experiment and temperature at 35 ℃, △E is still depleted while E1 and E2 are 94.9% and 99.7% depleted respectively. The noises of the samples can be derived from the values at room temperature and the thermal dependence of the leakage currents. With the addition of the noise of the pre-amplifier, the noises of E1, E2 and △E at 24 ℃ are 16.4, 16.3, and 10.5 keV （FWHM） respectively while at 35 ℃ are about 33.6, 33.1, and 20.6 keV （FWHM） respectively.
