五通道多层镜软X光能谱仪研制

五通道多层镜软X光能谱仪以光电导探测器(GaAs)作软X光探测器,为了消除杂散光影响,在多层镜通道后面加适当材料滤光片,构成谱仪探测系统,使用能量范围260～1200eV,谱仪在神光Ⅱ三倍频腔靶实验中、进行了实时考核,五通道全部测到软X光信号,基本达到预定的目标。     

砷化镓探测器的灵敏度研究

本文介绍了中子辐照损伤的砷化镓光电导探测器对强流γ脉冲辐射的响应。给出了掺铬砷化馆和本征砷化镓探测器的灵敏度随中子辐照损伤注量的变化规律及随着施加偏压的变化关系。     

一种超高速脉冲辐射探测器

本文介绍了一种新型的超高速脉冲辐射探测器——掺铬砷化镓(GaAs~1Cr)和本征砷化镓(GaAs)光电导探测器。此类探测器经中子辐照改性后。对短激光脉冲具有高速响应。测量结果表明:探测器的响应时间小于100ps;探测器的响应速度随中子辐照改性的剂量大小变化。而与它们的大小和施加偏压无关。     

小型X光二极管的研制

研制了小型X光二极管(XRD),可用于小型软X光能谱仪。小XRD与大XRD相比,体积为1／30。在“神光Ⅱ”上对小XRD进行了实验考核,结果表明：小XRD与传统的大XRD的时间响应和灵敏度基本一致．达到了预定的目标。对XRD的电路进行了分析．计算出XRD的时间响应和线性饱和电流。     

基于同步辐射光源的光电导探测器标定系统

将门控积分方法运用到光电导探测器的灵敏度标定中,发展了一套在北京同步辐射装置(BSRF)上对光电导探测器进行定时测量的方法,给出了利用这套标定系统在BSRF软X光站上对光电导探测器的测量结果。     

高功率Z箍缩软X射线功率测量

针对“强光一号”装置喷氪气高功率Z箍缩等离子体实验产生1keV以下的软X射线，研制了脉冲恒压电源驱动的镍薄膜量热计，测量Z箍缩软X射线总能量，用快时间响应的X射线二极管(XRD)探测器建立了软X射线功率测量系统，给出了实验测量结果。     

AXUV探测器标定及受辐照响应衰减研究

在EAST和HT-7装置上,具有宽能谱响应的AXUV光电二极管探测器主要用于辐射功率的绝对测量。探测器在经历多轮等离子体放电中的累积辐照效应后,观察到其表面发生变化。为了解探测器响应衰减程度,设计了相对标定实验,分别采用标准可见光光源和软X射线管作为标定光源,对EAST和HT-7实验中经历过不同放电次数的5个探测器进行了标定。标定结果表明,AXUV探测器在经历了EAST上约25 000次的等离子体放电累积辐照后,其在软X射线能段的响应下降约15%。而探测器在可见光能段的辐照损伤效应主要表现为同一个探测器不同通道之间对可见光响应的不一致性加剧。结合探测器在等离子体放电辐射场中的几何参数,对探测器受到的累积辐照剂量进行了估算。     

X光多层膜反射镜的损伤与破坏

X光多层膜反射镜是软X光光学尤其是X光激光研究的重要元件。随着X光激光的发展,X光多层膜反射镜的应用日益广泛,但产生X光激光的等离子体环境给X光多层膜反射镜的应用带来困难,最突出的就是等离子体发射的X光对多层膜的损伤与破坏。通过模拟实验,给出国产Mo/Si多层膜反射镜的破坏阈值小于0.10J/cm~2。在这个剂量辐照下,多层膜表面均方粗糙度明显增加,反射率几乎降至为零。根据这些结果,该文提出了防止多层膜反射镜破坏的一些想法。     

直流X射线模拟电缆X射线响应的可行性

本文对电缆X射线辐照响应的机理和模拟方法进行了研究,分析了电缆直流和脉冲X射线辐照响应的异同。建立了带状电缆X射线辐照响应一维计算模型,该模型包含电缆屏蔽层和介质层间隙、介质层瞬态辐射感应电导率等计算模型,模拟了带状电缆直流和脉冲X射线辐照电流响应。模拟结果表明,在X射线注量相同的条件下,电缆直流和方波脉冲X射线响应具有类似的波形特征及相同的间隙电压。因此,在该计算模型描述的电缆X射线辐照响应机制下,可利用直流X射线开展相应的脉冲X射线辐照响应机制模拟。     

经软X射线辐照的InP的表面损伤态

采用Ｘ光激发光电子能谱对经同步辐射软Ｘ光辐照的ＩｎＰ表面进行了分析。实验结果表明：ＩｎＰ表面辐照损伤与辐照Ｘ光的能量及剂量有关,尤其是具有近Ｐ原子Ｋ壳层共振吸收能量的软Ｘ光辐照与其它Ｘ射线辐照相比,其结果有所不同。文中就实验结果的机制进行了初步探讨。     

变宽度压弯椭圆柱面聚焦镜的光学参数可调性

由变宽度压弯椭圆柱面微聚焦镜理论,推导了聚焦镜光学参数(源距、像距和掠入射角)偏离设计值时所需的压弯力矩和镜面剩余斜率误差的计算公式.对上海光源硬X射线微聚焦光束线微聚焦镜进行了计算,结果表明,改变压弯力矩,微聚焦镜的源距和掠入射角可以在较大范围内调节,而较小范围的像距调节会产生较大的剩余斜率误差.     

Combining the “Kinetic Tandem” and the “Kinetic Stabilizer” Concepts

A novel means of MHD stabilizing axially symmetric mirror systems was proposed by Ryutov and demonstrated in the Gas Dynamic Trap at Novosibirsk. It relies on the strongly stabilizing effect exerted by low density plasma on the expanding field lines outside the mirrors. The “Kinetic Stabilizer Tandem Mirror” implements Ryutov’s technique by injecting axially directed ion beams into the expander. The ions, stagnated, and reflected by the converging magnetic field, form the stabilizing plasma. MHD stability code calculations show stabilization at beta values of 40%, with stabilizer beam powers that are small compared to the T-M fusion power output. Implicit in the calculations is the assumption that adequate “communication” exists between the plug plasmas and the stabilizer plasmas. This paper examines one means for enhancing communication: Utilize the stabilizer plasma to create a potential peak that, together with the plug potential, forms a potential well that traps and contains a “bridging” plasma.     

Confinement of Strongly Anisotropic Hot-ion Plasma in a Compact Mirror

The paper presents the results of recent study of anisotropic plasma with thermonuclear ions confined in the axially symmetric Gas Dynamic Trap (GDT) mirror. Anisotropic ions are produced by the perpendicular injection of two focused 18 keV neutral beams in the small mirror section attached to the GDT central cell. We observed build-up of density of anisotropic ions up to approximately 10¹³cm⁻³ with the localized spatial profile and the mean energy of 7 keV. The average fast ion density three times exceeded the background plasma density. Fast ion accumulation is accompanied by the decrease of the plasma flux from the central cell recorded outside the mirror, that was qualified as a potential barrier development causing confinement improvement. Analysis of measurement results compared with estimates of plasma parameters in the compact mirror allows to scale to the experiments with next generation neutral beams with increased power and pulse duration.     

Experimental Status of the HANBIT Facility

HANBIT is a magnetic mirror confinement device. Recent physics experiments have been mainly focused on identifying discharge characteristics and on getting stable plasma production and operation modes, by using a 500 kW slot antenna system at a fixed RF frequency of 3.5 MHz and varying discharge conditions such as fueling rate, RF power, and B-field intensity in central cell. Two distinct operation modes are found to be very sensitive to the RF power as well as the ratio of the RF frequency to the ion cyclotron frequency. A MHD interchange mode of m- -1 is clearly observed and the stabilizing mechanism can be explained by the sideband coupling theory.     

ICF实验中散射光角分布测量的数据分析系统

简要阐述了一个用旋转椭球镜和照相底片一次曝光获得激光惯性约束聚变实验中的散射光角分布信息的实验方法,介绍了其实验数据的分析处理方法并给出误差分析。     

古镜不取样的穆斯堡尔谱分析

本文对汉代一块青铜镜残片进行了~(119)Sn的穆斯堡尔谱分析。给出了透射谱与γ射线散射谱的对照,建立了一种无需取样的散射穆斯堡尔谱的测量方法。证实了该铜镜表面层锡是以Sn~4氧化物状态存在。     

Asphericalizing the Light Collection Mirror for the 200-Point Thomson Scattering Diagnostic Installed on the Large Helical Device

Shown is a possibility to make the image of a laser beam over a distance of 2.5 m, formed by the spherical multi-segment mirror installed in LHD, twice sharper ...     

RF plugging of mirror plasma

Discovery of superconducting materials that operate at high temperatures revive interest in the use of rf field for plasma confinement [1]. This paper discusses feasibility of a scheme where resonant rf cavities are attached to the mirror ends of an open system for plasma confinement.     

铜镜的快中子活化分析

利用中子发生器产生的快中子对50面古代青铜镜进行了快中子活化分析。铜镜标本取自不同朝代,采用比较分析法测定了铜镜中的铜、锡、铅三个组分的含量。文中介绍了测量过程中的具体方法和设备。