253 resultados para Télé-université
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
In this paper, we describe the structure and readout system of a two-dimension positional sensitive CsI(Tl) detector, and investigates the relation between energy lose and light output of the CsI(Tl) detector with secondary beams in intermediate energy.Bρ+(ΔE-TOF) method was used to distinguish the secondary beam.Linearity of the position signals of the CsI(Tl) was corrected.Energy signals from the CsI(Tl) detector were calibrated using the relationship of the Z, A and the light output response of the incid...中文摘要:描述了一种双维位置灵敏CsI(Tl)探测器的结构及其读出系统,用中能次级束研究其能损与光输出关系。使用Bρ+(ΔE-TOF)方法鉴别次级束,刻度了CsI(Tl)探测器位置信号的线性,并用其光输出与入射粒子的A、Z关系刻度其能量。结果表明,CsI(Tl)探测器输出信号的ADC读出与QDC读出(即其光输出)有很好的线性关系。
Resumo:
文中描述了一个5×5阵列CsI(Tl)探测器结构以及对轻带电粒子的鉴别,CSI晶体有快慢两种成分。通过不同延迟和积分门的选择得到这两种信号,来进行轻带电粒子的鉴别。经过理论模拟和实验测试,发现不同的延迟和门的宽度对鉴别能力都有影响。
Resumo:
实验测试了中国科学院近代物理研究所制备的9根大尺寸闪烁晶体样品(40 mm×40 mm×300 mm)的光输出及其非均匀性。使用了多种光反射材料和包装方法对样品进行包装,对其光输出及其非均匀性进行测试。对实验数据进行分析,确定了大尺寸晶体的最佳读出端和包装方法。在测试中,所有CsI(Tl)闪烁晶体样品的光输出非均匀性均好于7%,部分样品可达到2%左右。结合本次实验结果,对影响CsI(Tl)晶体光输出非均匀性的因素进行了简要分析。
Resumo:
本文介绍了近代物理研究所自行生长的CsI(Tl)晶体用于γ射线及重离子能量测量的结果。测量662keVγ射线时得到好于10%的能量分辨(采用光电倍增管读出),同时光输出可达到同类型晶体的130%;测量能量为30MeV/u左右的重离子时得到好于2%的能量分辨(采用光二极管读出)。
Resumo:
利用能量为170MeV的35Cl束流,通过157Gd(35Cl,4n)熔合蒸发反应研究了188Tl的高自旋态能级结构.依据实验结果建立了188Tl基于πh9/2(?)vi13/2组态的转动带.根据双奇Tl核能级结构的相似性,指定了188Tlπh9/2(?)vi13/2扁椭球转动带的自旋值.结果表明在188Tl中,πh9/2(?)vi13/2扁椭球转动带在低自旋区具有旋称反转性质.利用包含了质子-中子剩余相互作用的准粒子-转子模型,定性地解释了πh9/2(?)vi13/2扁椭球转动带的低自旋区旋称反转现象.
Resumo:
描述了一种双维位置灵敏CsI(Tl)探测器 .用 3组分α源测量该探测器得到的位置分辨为0 .81mm(FWHM) ,对于 6 9MeV/u36 Ar能量分辨为 0 .9% (FWHM) .在RIBLL的ΔE E粒子鉴别望远镜中常常作为E探测器 .由于CsI(Tl)晶体对不同的粒子的能损 -光输出的非线性 ,需要针对不同离子对CsI探测器作能量 光输出校正曲线 .
Resumo:
基于GEANT4模拟了HIRFL CSRm内靶实验终端的CsI(Tl)电磁量能器系统,给出了CsI电磁量能器的最佳设计参数及可能达到的性能.结果表明,设计的CsI(Tl)电磁量能器系统能够满足所研究的物理要求.
Resumo:
利用能量为 1 6 7— 1 75MeV的35Cl束流 ,通过16 0 Gd(35Cl,5n)熔合蒸发反应研究了190 Tl的高自旋态能级结构 .实验建立了190 Tl基于πh9/2 νi13/2 组态的转动带 .在束测量结果和194 Biα衰变的α γ测量结果确定地指定了190 Tl的πh9/2 νi13/2 转动带的自旋值 .基于自旋指定 ,发现了190 Tl的πh9/2 νi13/2 扁椭球转动带在低自旋时旋称反转 .这是首次在基于πh9/2 νi13/2 组态的扁椭球转动带中观测到旋称反转 .考虑了质子 -中子剩余相互作用的粒子 -转子模型能够解释πh9/2 νi13/2 扁椭球转动带的低自旋旋称反转 .
Resumo:
根据核反应过程中发射带电粒子在硅半导体中的最大能量沉积 ,利用带电粒子在硅半导体中的阻止本领曲线 ,同时实现半导体探测器的厚度确定及与之组合的CsI(Tl)的刻度
Resumo:
Large-sized CsI (Tl) single crystals, similar to phi 100 mm x 350 mm, have been grown successfully, and this CsI(Tl) coupled with PD has been successfully utilized at RIBLL (the Radioactive Ion Beam Line in Lanzhou) to measure the energy of heavy ions as a stopping detector. The performances of CsI(Tl) detector coupled with PD and APD have been tested and compared, including the temperature dependence of scintillating light yield
Resumo:
The temperature dependences of the light output of CsI(Tl) crystal grown at IMP and of the gain of the Hamamatsu S8664-1010 avalanche photodiode (APD) have been investigated systematically. The light output of the CsI(Tl) crystal increases with temperature by 0.67%/degrees C in the region from -2 degrees C to 8 degrees C, and by 0.33%/degrees C in the region from 8 degrees C to 25 degrees C, while the gain of the tested APD decreases by -3.68%/degrees C (working voltage 400V) on average in the room temperature range. The best energy resolution 5.1% of the CsI(Tl) with APD was obtained for the 662keV gamma ray from Cs-137 radiation source.
Resumo:
Excited states in Tl-188 have been studied experimentally using the Gd-157(Cl-35;4n) reaction at a beam energy of 170 MeV. A rotational band built on the pi h(9/2) x nu i(13/2) configuration with oblate deformation has been established for Tl-188. Based on the structure systematics of the oblate pi h(9/2) x nu i(13/2) bands in the heavier odd-odd Tl nuclei, we have tentatively proposed spin values for the new band in Tl-188. The pi h(9/2) x nu i(13/2) oblate band in Tl-188 shows low-spin signature inversion, and it can be interpreted qualitatively by the two-quasiparticle plus rotor model including a J-dependent p-n residual interaction.