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
2D position sensitive, single-sided Si stripixel detector was selected as the one of the two main components of the Si vertex tracker (Si SVX) in the upgraded PHENIX detector at RHIC (relativistic heavy ion collider) ...2D position sensitive, single-sided Si stripixel detector was selected as the one of the two main components of the Si vertex tracker (Si SVX) in the upgraded PHENIX detector at RHIC (relativistic heavy ion collider) in Brookhaven National Laboratory (BNL). This is the first large scale application of the novel Si stripixel detector in a real large experiment after many years of research and development at BNL. The first and second prototype fabrication runs of the SVX stripixel detectors were carried out successfully in BNL’s Si detector development and processing Lab. The processing of these stripixel detectors is similar to that for the standard single-sided strip detectors: one-sided processing, single implant for the pixel (strip) electrodes, etc. The only additional processing step is the double metal process, a technology that is simple and well matured by many Si detector processing industries and labs, including BNL. The laser and beam tests on those prototype detectors show the 2D position sensitivity and good position resolution in both X and U coordinates (about 25 μm for 80 μm pitch). For the mass production of 400 sensors needed for the Si SVX, the processing technology has been successfully transferred to the industrial: Hamamatsu Photonics (HPK). HPK has produced a pre-production run of stripixel sensors with the full PHENIX SVX specification on 150 mm diameter wafers. The laser tests on these pre-production wafers show good signal to noise ratio (about 20∶1).展开更多
A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting t...A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting the tunable circuit, the matched bandwidth is achieved as wide as possible. Experi- mental results show that the pulse response time of the detector is less than 150 ps within random carrier signal 500 MHz bandwidth range between 35 GHz to 39 GHz via tuning circuit. The detector is very easy to operate because it does not need bias current or synch-pulse source.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Project(DE-Ac02-98CH10886) supported in part by the US Department of Energy
文摘2D position sensitive, single-sided Si stripixel detector was selected as the one of the two main components of the Si vertex tracker (Si SVX) in the upgraded PHENIX detector at RHIC (relativistic heavy ion collider) in Brookhaven National Laboratory (BNL). This is the first large scale application of the novel Si stripixel detector in a real large experiment after many years of research and development at BNL. The first and second prototype fabrication runs of the SVX stripixel detectors were carried out successfully in BNL’s Si detector development and processing Lab. The processing of these stripixel detectors is similar to that for the standard single-sided strip detectors: one-sided processing, single implant for the pixel (strip) electrodes, etc. The only additional processing step is the double metal process, a technology that is simple and well matured by many Si detector processing industries and labs, including BNL. The laser and beam tests on those prototype detectors show the 2D position sensitivity and good position resolution in both X and U coordinates (about 25 μm for 80 μm pitch). For the mass production of 400 sensors needed for the Si SVX, the processing technology has been successfully transferred to the industrial: Hamamatsu Photonics (HPK). HPK has produced a pre-production run of stripixel sensors with the full PHENIX SVX specification on 150 mm diameter wafers. The laser tests on these pre-production wafers show good signal to noise ratio (about 20∶1).
基金supported by the National Natural Science Foundation of China under Grant No. 60801028the Specialized Research fund for the Doctoral Program of Higher Education of China under Grant No. 20070614034
文摘A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting the tunable circuit, the matched bandwidth is achieved as wide as possible. Experi- mental results show that the pulse response time of the detector is less than 150 ps within random carrier signal 500 MHz bandwidth range between 35 GHz to 39 GHz via tuning circuit. The detector is very easy to operate because it does not need bias current or synch-pulse source.
