Radioactive Ion Beam Line in Lanzhou (RIBLL) is the heavy ion radiation beam equipment on Heavy Ion Accelerator in Lanzhou, which can provide a variety of Radioactive Ion Beam （RIB）for physical experiments.In order ...Radioactive Ion Beam Line in Lanzhou (RIBLL) is the heavy ion radiation beam equipment on Heavy Ion Accelerator in Lanzhou, which can provide a variety of Radioactive Ion Beam （RIB）for physical experiments.In order to improve the efficiency and accuracy of the experiments, we need a high-performance Parallel Plate Avalanche Counter(PPAC) to monitor the RIB online and to measure the track of the incident particles and reaction products.展开更多
The heavy-ion therapy is one of the modalities to treat a patient with body tumors. In the tumor therapy, we wish to irradiate only the tumors in order to keep the normal tissues/organs undamaged. Along the range of h...The heavy-ion therapy is one of the modalities to treat a patient with body tumors. In the tumor therapy, we wish to irradiate only the tumors in order to keep the normal tissues/organs undamaged. Along the range of heavy ion passing through the matter, most of ion energy deposits at the end of the range, forming a so called Bragg peak[1]. In order to accurately determine the irradiation profiles and positions of scanned展开更多
The prompt fission neutron spectrum(PFNS)is a key nuclear data quantity that is of particular interest and plays a crucial role in understanding and modeling fission processes.An array comprising 48 liquid scintillati...The prompt fission neutron spectrum(PFNS)is a key nuclear data quantity that is of particular interest and plays a crucial role in understanding and modeling fission processes.An array comprising 48 liquid scintillation detectors and a parallelplate avalanche counter(PPAC)was developed at the China Institute of Atomic Energy(CIAE)to measure the PFNS of actinide nuclei.Efficiency and energy calibrations were performed for all the liquid scintillators,and their efficiencies were consistently found to be better than 5%.The time resolutions of the PPAC and liquid scintillators were measured to be 1.08 ns and 1.16 ns using~(252)Cf and~(207)Bi sources,respectively.The pulse shape discrimination of the liquid scintillator was utilized to identify neutron andγsignals on an event-by-event basis,and the figure of merit was deduced as 1.12 at a 200 ke Vee threshold.The contribution to the PFNS from multiple scattered neutrons was evaluated via Geant4 simulations,and those originating from the environment were found to be comparable to the crosstalk between the detectors.The neutron efficiency of the entire detection array was calibrated using a~(252)Cf spontaneous fission source and was demonstrated to be consistent with the Geant4 simulation results,which verified the reliability of the detection array.展开更多
ZTE Corporation has reported that the Patent Protection Association of China （PPAC） recently released patent application rankings for 2009 with ZTE, Huawei and Hongfujin claiming the top three spots on the ranking l...ZTE Corporation has reported that the Patent Protection Association of China （PPAC） recently released patent application rankings for 2009 with ZTE, Huawei and Hongfujin claiming the top three spots on the ranking list.展开更多
文摘Radioactive Ion Beam Line in Lanzhou (RIBLL) is the heavy ion radiation beam equipment on Heavy Ion Accelerator in Lanzhou, which can provide a variety of Radioactive Ion Beam （RIB）for physical experiments.In order to improve the efficiency and accuracy of the experiments, we need a high-performance Parallel Plate Avalanche Counter(PPAC) to monitor the RIB online and to measure the track of the incident particles and reaction products.
文摘为提升平行板雪崩计数器(PPAC)的使用性能,设计了一款具有50 ns和100 ns两档达峰时间的四通道滤波成形专用集成电路(ASIC)芯片。该ASIC芯片与已有的前放芯片结合可实现PPAC的信号读出。芯片内每个通道包括极零相消、低通滤波成形及输出电路。输入动态范围-0.8^+0.8 V内的线性度达到0.2%;-3 d B带宽噪声不高于60μV;芯片功耗30 m W;面积为2.6 mm×1.25 mm。
文摘The heavy-ion therapy is one of the modalities to treat a patient with body tumors. In the tumor therapy, we wish to irradiate only the tumors in order to keep the normal tissues/organs undamaged. Along the range of heavy ion passing through the matter, most of ion energy deposits at the end of the range, forming a so called Bragg peak[1]. In order to accurately determine the irradiation profiles and positions of scanned
基金supported by Continuous-Support Basic Scientific Research Project(No.BJ010261223282)the National Natural Science Foundation of China(Nos.U2167201,11975318)+2 种基金the State Key Laboratory of Nuclear Physics and TechnologyPeking University(No.NPT2023KFY01)the Research and Development Project of China National Nuclear Corporation。
文摘The prompt fission neutron spectrum(PFNS)is a key nuclear data quantity that is of particular interest and plays a crucial role in understanding and modeling fission processes.An array comprising 48 liquid scintillation detectors and a parallelplate avalanche counter(PPAC)was developed at the China Institute of Atomic Energy(CIAE)to measure the PFNS of actinide nuclei.Efficiency and energy calibrations were performed for all the liquid scintillators,and their efficiencies were consistently found to be better than 5%.The time resolutions of the PPAC and liquid scintillators were measured to be 1.08 ns and 1.16 ns using~(252)Cf and~(207)Bi sources,respectively.The pulse shape discrimination of the liquid scintillator was utilized to identify neutron andγsignals on an event-by-event basis,and the figure of merit was deduced as 1.12 at a 200 ke Vee threshold.The contribution to the PFNS from multiple scattered neutrons was evaluated via Geant4 simulations,and those originating from the environment were found to be comparable to the crosstalk between the detectors.The neutron efficiency of the entire detection array was calibrated using a~(252)Cf spontaneous fission source and was demonstrated to be consistent with the Geant4 simulation results,which verified the reliability of the detection array.
文摘ZTE Corporation has reported that the Patent Protection Association of China （PPAC） recently released patent application rankings for 2009 with ZTE, Huawei and Hongfujin claiming the top three spots on the ranking list.
