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1.
通过55Mn(30Si,αpn)反应布居了79Kr的高自旋态.用GASP阵列配以由40个ΔE×ESi(Au)望远镜所组成的带电粒子球实现γγγ-带电粒子符合测量.观测到由相对强度为(2.7±0.3)%的8条级联γ跃迁所组成的79Kr高自旋超形变转动带.除了在转动频率ω>0.95MeV处急剧下降外,该带的动力学转动惯量近乎常数(22ñ2/MeV)并被解释为具有四极形变参数β2=0.51以及本征侵入组态为π50ν51. High-spinstates in 79Kr were populated via the fusion evaporation reaction 55Mn (30Si,αpn)at 130 MeV.Promptγ γγ charged particle coincidences were measured by using the GASP array in conjunction with the ΔE×E Si(Au) charged particle ball.Asu perdeformed band consisting of 8 γ ray transitions with an intensity of (2.7±0.3)% has been indentified in 79Kr.The dynamic moment of inertia for the band is nearly constant at approxately 22ñ2/MeV below arotational frequency of 0.95 MeV...  相似文献   

2.
用气体放电法研究含氘金属异常现象时,发现有X射线产生.因此用吸收法、特征X射线法和NaI闪烁计数器测量了X射线能量,用7Li热释光片估测了X射线强度.吸收法测出的X射线平均能量为(26.9±2.2)keV和NaI闪烁计数器测出的(26.0±2.4)keV单能X射线在测量误差内相符. X rays were observed to create when the anomalous phenomenon in the metal loaded with deuterium studied by the gas-discharge method. Therefore the X-ray energy spectra were measured by the absorption method, the specific X-ray approach and the NaI scintillation counter, while X-ray intensity was estimated by using 7Li thermoluminescent foils. The X-ray average energy measured by the absorption method is 27. 6±2. 1keV,whlch is fitted within the error extent to 26. 0±2. 4keV monoenergetic Xrays  相似文献   

3.
10MeVLIA加速电压、电子束流测试   总被引:3,自引:2,他引:1       下载免费PDF全文
描述了中物院流体物理研究所10MeV电子直线感应加速器(10MeVLIA)加速电压、电子束流波形测试方法,主要介绍了为探测加速腔电压波形而设计的电容性高压脉冲探头(CVP探头)及其测试方法,并介绍了用电阻环四象限点监测束流质心位置及束流强度的方法。  相似文献   

4.
The multilayer (ML) mirror with high-reflectivity (HR) at a specific emission line of 19.5 nm (Fe line) and low-reflectivity (LR) at 30.4 nm (He line) is needed to be designed and fabricated for observing the image of sun. Based on a variety of optimizations utilized different structures, the design is performed and the final results demonstrate that the reflectivity at 30.4 nm does not achieve minimum value when the reflectivity at 19.5 nm reaches the maximum value. The tradeoff should be done between the HR at 19.5 nm and LR at 30.4 nm. One optimized mirror is fabricated by direct current magnetron sputtering and characterized by grazing-incident X-ray diffraction (XRD) and synchrotron radiation (SR). The experimental results demonstrate that the ML achieves the reflectivity of 33.3% at 19.5 nm and of 9.6× 10-4 at 30.4 nm at the incident angle of 13°.  相似文献   

5.
The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.  相似文献   

6.
Through the use of time and space integrated kiloelectronvolt (keV) spectroscopy, we investigate the thermal emission of plasma, which produces strong line emission from the titanium K shell (He-a at 4.7 keV and H-α at 4.9 keV), created by laser. In order to optimize the conversion efficiency enhancement on titanium foils, the experiment is conducted under a variety of laser-driven intensity conditions. The X-ray emission intensity at 4.7 keV is measured and compared with prediction. The experimental result demonstrates that the solid Ti target laser-produced plasma (LPP) source has X-ray emission at 4.7 keV, which are all generated from electronic transitions in Ti ions at pulse width of 2.1 ns or 30 ps, the crudely evaluated He-α X-ray intensity appears to slightly increase with laser intensity enhancement, and the pre- pulse effect increases the conversion efficiency of the He-α X-ray. In addition, a 90-μm-thick Ti foil as a filter is used to transmit He-α X-ray at near 4.7 keV, creating a quasi-monochromatic transmission and greatly reducing the lower- and higher-energy background.  相似文献   

7.
Phosphorus-doped ZnO (ZnO:P) thin films are deposited on a c-plane sapphire in oxygen at 350℃, 450℃, 550℃ and 650℃, respectively, by pulsed laser deposition (PLD), then all the ZnO:P samples are annealed at 650℃ in oxygen with a pressure of 1 × 10^5 Pa. X-ray diffraction measurements indicate that the crystalline quality of the ZnO:P thin films is improved with the increasing substrate temperature from 350℃ to 550℃. With a further increase of the deposition temperature, the crystalline quality of the ZnO:P sample is degraded. The measurements of low-temperature photoluminescence spectra demonstrate that the samples deposited at the substrate temperatures of 350℃ and 450℃ show a strong acceptor-bound exciton (A^0X) emission. The electrical properties of ZnO:P films strongly depend on the deposition temperature. The ZnO:P samples deposited at 350℃ and 450℃ exhibit p-type conductivity. The p-type ZnO:P film deposited at 450℃ shows a resistivity of 1.846Ω·cm and a relatively high hole concentration of 5.100 × 10^17 cm^-3 at room temperature.  相似文献   

8.
综述了离子束材料实验室在高剂量与高能量离子注入研究方面的新进展,包括高剂量离子注入动态靶的模拟计算MACA程序、多能离子注入深度分布计算、MeV离子引起的HOPG表面操作、MeV离子诱变右旋糖酐生产菌种、高剂量离子注入在45号钢表面形成耐腐蚀的保护层以及在高速工具钢上形成含有大量超细碳化物的耐磨层. The development of high dose ion implantation and high energy ion implantation at the Ion Beam Application Group of IHIP in recent years is reviewed.  相似文献   

9.
Tungsten is regarded as an important candidate of plasma facing material in international thermonuclear experimental reactor (ITER), so the determination and modeling of spectra of tungsten plasma, especially the spectra at high temperature were intensely focused on recently. In this work, using the atomic structure code of Cowan, a collisional radiative model (CRM) based on the spin-orbit-split-arrays is developed. Based on this model, the charge state distribution of tungsten ions is determined and the soft X-ray spectra from high charged ions of tungsten at different temperatures are calculated. The results show that both the average ionization charge and line positions are well agreed with others calculations and measurements with discrepancies of less than 0.63% and 1.26%, respectively. The spectra at higher temperatures are also reported and the relationship between ion abundance and temperature is predicted in this work.  相似文献   

10.
The atomic and electronic structures of T1 and In on Si(111) surfaces are investigated using the firstprinciples total energy calculations. Total energy optimizations show that the energetically favored structure is 1/3 ML T1 adsorbed at the T4 sites on Si(111) surfaces. The adsorption energy difference of one T1 adatom between (√3 × √3) and (1 × 1) is less than that of each In adatom. The DOS indicates that TI 6p and Si 3p electrons play a very important role in the formation of the surface states. It is concluded that the bonding of TI adatoms on Si(111) surfaces is mainly polar covalent, which is weaker than that of In on Si(111). So T1 atom is more easy to be migrated than In atom in the same external electric field and the structures of T1 on Si(111) is prone to switch between (√3 × √3) and (1 × 1).  相似文献   

11.
瞬态光学渡越辐射测量系统的设计   总被引:1,自引:0,他引:1  
针对在神龙一号上进行电子束瞬态发射度的测量要求,建立了一套利用光学渡越辐射原理进行电子束发射度测量的瞬态测量系统,该测量系统瞬态测量时间最快约10ns,并获得了神龙一号发射的脉冲电子束的束斑及发散角,典型值分别为约9mm和10.5mrad,实现了电子束发散角和束斑的同时测量,为在神龙一号上进行的时间分辨测量系统的研究奠定了基础。  相似文献   

12.
针对在神龙一号上进行电子束瞬态发射度的测量要求,建立了一套利用光学渡越辐射原理进行电子束发射度测量的瞬态测量系统,该测量系统瞬态测量时间最快约10 ns,并获得了神龙一号发射的脉冲电子束的束斑及发散角,典型值分别为约9 mm和10.5 mrad,实现了电子束发散角和束斑的同时测量,为在神龙一号上进行的时间分辨测量系统的研究奠定了基础。  相似文献   

13.
双脉冲电子束源实验研究   总被引:7,自引:4,他引:3       下载免费PDF全文
 利用现有2MeV直线感应注入器,通过改造,将其次级功率源和8个感应腔分成2组,使之交替工作,建立了一台双脉冲电子束源。二极管电压脉冲幅度达到1MeV,电子束脉冲持续时间为120ns,脉冲间隔可以根据需要在100~500ns间进行调节。实验结果表明:该双脉冲电子束源可以产生双脉冲电子束,其电压幅度差值小于2%,束流可达3kA,并且工作稳定,利用该装置可以进行多脉冲二极管物理和天鹅绒多脉冲发射特性实验研究。  相似文献   

14.
利用现有2MeV直线感应注入器,通过改造,将其次级功率源和8个感应腔分成2组,使之交替工作,建立了一台双脉冲电子束源。二极管电压脉冲幅度达到1MeV,电子束脉冲持续时间为120ns,脉冲间隔可以根据需要在100~500ns间进行调节。实验结果表明:该双脉冲电子束源可以产生双脉冲电子束,其电压幅度差值小于2%,束流可达3kA,并且工作稳定,利用该装置可以进行多脉冲二极管物理和天鹅绒多脉冲发射特性实验研究。  相似文献   

15.
本文简要介绍了1.5MeV LIA脉冲功率系统的结构、组成和设计思想;给出了开关运行参数和确定开关时间抖动指标的方法、闭环系统的总抖动对加速电压相对变化的影响、脉冲功率系统各段输出波形和电压幅度的调制关系;测量结果表明,1.5MeV LIA的运行功率和时间同步满足总体设计要求。  相似文献   

16.
2MeV有箔注入器的束流调试   总被引:5,自引:5,他引:0       下载免费PDF全文
 为20MeV 直线感应加速器建造的2MeV注入器的束流技术指标经过一年多实验调试已达到能量2MeV、束流3kA、亮度≥108A/(m·rad) 2。建立了二维数字模型对注入器的电子发射和束流传输过程进行模拟,模拟结果指导了实验调试,分析了有箔二极管中发生的聚焦作用。  相似文献   

17.
为20MeV 直线感应加速器建造的2MeV注入器的束流技术指标经过一年多实验调试已达到能量2MeV、束流3kA、亮度≥108A/(m·rad)2。建立了二维数字模型对注入器的电子发射和束流传输过程进行模拟,模拟结果指导了实验调试,分析了有箔二极管中发生的聚焦作用。  相似文献   

18.
10MeVLIA强流电子束的输运   总被引:6,自引:5,他引:1  
介绍了10MeV直线感应加速器(LIA)束输运系统布局及实验的调试规律。分析了束横向运动对束稳定输运的影响,理论分析和实验调试的结果表明,抑制束稳定输运的主要障碍来自束的横向运动。当束稳定输运时,可获得束能10.4MeV,束流强度2.6kA,束半高宽约100ns的强流脉冲电子束。  相似文献   

19.
强流直线感应加速器束流智能调谐系统设计   总被引:2,自引:2,他引:0       下载免费PDF全文
 介绍了正在研究设计的调谐强流电子束束心轨迹的计算机智能系统。根据目前正在设计建造的 “神龙一号”加速器束流输运环境,为抑制束心螺旋运动,适应束输运磁场元件无散热装置,调谐过程中应尽量减少实验次数,智能调谐方法主要采用数值模拟和计算机克隆调谐和人工调谐相结合。以束心轨迹的数值模拟为基础,对束心位置调谐过程中的核心部分二极场调谐磁元件的调谐特性曲线进行了数值模拟,并与实验获得的调谐特性曲线进行了比较。获得了数值模拟和实验的初步结果。  相似文献   

20.
通过针孔成像法得到X光源强度空间分布图像,直接读取图像数据得到X光源的半高宽焦斑(FWHM)尺寸,对图像数据进行傅里叶变换得到调制传递函数,并计算得到X光源的等效焦斑尺寸(50%MTF)。应用针孔成像法测量多脉冲电子直线感应加速器产生的X光源焦斑尺寸,测量结果表明,加速器性能稳定。定义焦斑形状因子参数并用于描述X光源分布,结果表明,该加速器X光源分布在高斯分布和本涅特分布之间变化。  相似文献   

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