双维位置灵敏CsI(Tl)探测器

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69MeV/u ³⁶Ar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.     

27,28P+28Si总反应截面增强及可能相关的机制

测量了27,28P和相应同中子异位素在28Si靶上的中能反应截面.测得N=12和13同中子异位素的反应截面在Z=15处突然增大.对Z≤14同中子异位素和28P的实验数据结果可以用改进的光学极限近似的Glauber理论很好地描述.28P的反应截面能够用扩大核芯以改进的Glauber理论来解释.但是,用改进光学极限和少体近似的Glauber理论却低估了27P的实验数据.理论分析表明,扩大的核芯加质子晕可能是响应27P+28Si反应截面增强的机制. The reaction cross sections of~(27,28)P and the corresponding isotones on Si target were measured at intermediate energies. The measured reaction cross sections of the N=12 and 13 isotones show an abrupt increase at Z=15. The experimental results for the isotones with Z≤14 and~(28)P can be described well by the modified Glauber theory of the optical limit approach. The enhancement of the reaction cross section for~(28)P could be explained by the modified Glauber theory with an enlarged core. Theoretical ana...     

RIBLL终端LASCAR闪烁体阵列探测器研制进展

介绍了RIBLL终端LASCAR闪烁体阵列探测器的工作原理和结构特点. 描述了为满足放射性核束实验的要求而对阵列所作的重要改进. 给出了LASCAR构型优化改造的工作设想和实施步骤. The principles and structure characteristics of LASCAR scintillator array detector at RIBLL terminal are described. Special emphases are laid upon the latest progress for the development of LASCAR array detector to meet the requirements of the RIB experiments. The working plan and steps for optimizing configuration of the LASCAR multi unit neutron scintillator array detector are also presented.     

兰州放射性核束流线 *

描述了兰州重离子加速器国家实验室最近建成并已投入运行的新装置———兰州放射性核束流线 (RIBLL) .RIBLL是PF型双消色差反对称结构放射性核束分析设备 ,它的立体角接收度≥ 6 .5msr,动量接受度± 5 % ,最大磁刚度4.2Tm ,元素分辨>150 ,质量分辨>300 ,最短分辨时间 <1μs.初级束流的入射角在 0°～ 5°范围可调 .RIBLL已为第一批物理实验提供¹⁷N ,⁸He等多种放射性核束流 .     

RIBLL束流诊断

描述了兰州放射性离子次级束流线(RIBLL)上研制并安装使用的放射性束流(RIB)诊断装置的种类、结构、性能及在AIBLL上的位置和功能.重点叙述了以光纤为基础的几种诊断元件,它们探测效率高、响应时间快、制作容易、性能稳定.给出了RIB¹⁷N等高图,说明诊断装置辅助MBLL得到RIB的水平.     

双维位置灵敏CsI(Tl)闪烁探测器

介绍了一种双维位置灵敏CsI(Tl)闪烁探测器, 利用GEANT4对它进行了蒙特卡罗模拟, 得到了RIB 17N的位置分布谱及探测器的空间位置分辨,　模拟结果与实验测量值很好地吻合。给出了影响探测器分辨的主要因素及改进方案。A two dimensional position sensitive CsI(Tl) scintillation detector readout with PSPMT was introduced. The performance of detector was simulated by using Monte Carlo code GEANT4. The position spectrum of RIB 17N and the detector’s position resolution were obtained, and the simulation results accorded with the experimental ones. The main factors, which can affect performance of the detector, and some planned detector improvements were presented.     

P同位素的质子滴线核研究

研究了在相对论平均场近似下P同位素的滴线核的性质,首先在理论上探讨了25P作为P的滴线核存在的可能性及其可能具有的质子晕结构,然后给出了在兰州放射性束流装置上25P的实验鉴别结果. Great progress was made on the study of P isotope both in theory and in experiments, but the final conclusion about the dripline of P isotope has not been made. In this article the properties of P isotope was studied in the frame work of relativistic mean field (RMF). First the probability of 25P as the dripline nuclei of P isotope and the proton halo structure of 25P was discussed, and then the RIBLL experiental result of 25P is presented.     

利用改进的Glauber模型对非奇异核核反应总截面数据的拟合

在对反应总截面的理论计算中,现有的理论计算值与实验数据在高能区可以很好的符合，但在中能区理论值低于实验值约10％—20％.通过对计算核反应总截面的Glauber模型加入有限程修正，并对输入的核物质密度分布采用双参数的费米密度分布形式.计算结果表明，理论计算值对于没有奇异结构的核在低中能区和高能区，都与实验数据很好符合.     

RIBLL束流诊断的发展

描述了重离子加速器放射性次级束流线束流诊断技术的新发展,它包括初级束流在线监测研制的非拦截式法拉第筒,监测低强度初级束流的塑料闪烁探测器,测量放射性次级束流剖面的大面积双维位置灵敏平行板雪崩室等.这些新研制的束流诊断装置的运用,明显提高了设置、调整、确定重离子加速器放射性次级束流线运行参数的速度和准确性,改善了放射性次级束流纯度和质量,并使得重离子加速器放射性次级束流线的运行更简洁、迅速和有效.     

Possible Experimental Evidence of a Moderate Proton Halo in ^29S

The total reaction cross sections (TRCSs) of^29S ^28Si have been measured at intermediate energies. An obvious enhancement in TRCS of ^29S is observed as compared with its neighbouring nuclei. The TRCSs of ^29S ^28Si arecal culated with the modified Glauber theory in the optical limit and few-body approaches. The different factor d as a possible measure of halo appearance is deduced from the experimental and theoretical data. It is well accepted that ^27p is a proton halo nucleus. Although not as anomalous as ^27p, the different factor d of ^29S is obviously larger than that of its neighbouring isotones of N = 13. This result indicates that a moderate proton halo may exist in ~9S nucleus. We calculate the total reaction cross sections for ~9S with the modified Glaubertheory as a function of incident energy and compare the results with those for 2rSi which is a core nucleus 0f29S.The measured TRCSs of 27Si4-2SSi can be described to be satisfactory by the modified Glauber theory of theoptical limit approach. Although a diffused nuclear density distribution is used, the theories still inadequatelypredict the experimental TRCSs of 29S4-2SSi, which further indicates the possibility of proton halo in 29S.