HIRFL-CSR电子冷却装置高精度螺线管线圈制作及磁场测量

 采用特殊工艺制作了HIRFL-CSR电子冷却装置冷却段高精度螺线管线圈,两个产生反向磁场的线圈同轴、平行地放置在特制的测量装置上,高精度霍尔探头位于测量装置中心平面上,探头测量面与测量装置轴线重合,测量单个线圈磁场的横向分量,调节线圈几何轴相对于测量装置轴线的夹角,测得线圈磁轴的偏角小于1×10^-3。     

合肥同步辐射光源波动器UD-1物理设计

 介绍了国家同步辐射实验室二期工程新建波动器UD-1的物理设计，给出了设计参数和主要技术要求。从储存环电子束流的要求和用户对光源的要求两方面分析了波动器磁场品质应满足的技术指标，给出UD 1的磁场一次积分值应小于2×10^-4T·m，二次积分值应小于2×10^-4T·m ²,相位误差应小于10°。     

HIAF电子冷却装置高精度线圈磁轴测量

强流重离子加速器装置（HIAF）将采用电子冷却技术,降低重离子束流的发射度和动量分散,提高核物理及原子物理实验的精度与亮度。电子冷却装置的冷却段磁场均匀度是影响冷却效率的主要参数,HIAF电子冷却装置采用多个独立高精度线圈串联产生纵向磁场的设计,获得极高的冷却段磁场均匀度。本文介绍了一种测量高精度线圈磁轴偏角的装置,采用定位装置测量线圈的几何对称轴,通过旋转霍尔探头测量线圈中心平面上的径向与轴向磁场分布,再根据磁场测量数据计算出线圈磁轴与几何对称轴之间的偏角。实际测量表明该装置的磁轴偏角测量精度达到±0.10 mrad。测量得到的HIAF电子冷却装置冷却段线圈样品的磁轴偏角为（1.28±0.10）mrad,达到设计要求。     

HIRFL-CSRe二极铁积分磁场测量

 介绍了兰州重力加速器冷却储存环实验环二极磁铁积分长线圈测磁装置的构成，描述了实验环二极铁的分散性测量、横向分布测量、传递函数等测量内容及测量方法。实验环二极铁采用不断地加减硅钢铁片垫补和加调整线圈电流的方法来调整二极磁铁的有效长度来改变分散性。通过垫补和测量，二极磁铁的分散性在优化磁场时达到±2×10^-4。同时给出了二极铁的横向分布和传递函数的测量结果。对二极铁的设计和加工进行了修正。     

准分子激光用矩形脉冲磁场线圈的研制

 叙述用于准分子激光实验的矩形磁场线圈的设计、加工工艺及实验结果。该线圈内表面尺寸为925×425×100mm³，用此线圈在激光腔内得到了磁感应强度为0.225T的磁场，在准分子激光实验中明显地改善了电子束的均匀性。     

飞秒激光与固体靶相互作用中自生磁场的测量

 利用OMA光学多道分析谱仪，分别在激光镜反方向和接近靶面法线方向测量了2倍频谐波的精细结构。在激光功率密度为5×10¹⁷ W/cm²的条件下，通过散射光2倍频谐波谱的精细结构，回推出激光与等离子体相互作用中产生的自生磁场达100T量级。     

AlGaN/AlN/GaN结构中二维电子气的输运特性

对使用金属有机物汽相沉积法生长的AlGaN/AlN/GaN结构进行的变温霍尔测量，测量结果指出在AlN/GaN界面处有二维电子气存在且迁移率和浓度在2K时分别达到了1.4×10⁴cm²·V^-1·s^-1和9.3×10¹²cm^-2，且在200K到2K范围内二维电子气的浓度基本不变，变磁场霍尔测量发现只有一种载流子(电子)参与导电.在2K温度下，观察到量子霍尔效应，Shubnikov-de Haas (SdH) 振荡在磁场约为3T时出现，证明了此结构呈现了典型的二维电子气行为.通过实验数据对二维电子气散射过程的半定量分析，推出量子散射时间为0.23ps，比以往报道的AlGaN/GaN结构中的散射时间长，说明引入AlN层可以有效减小合金散射，进一步的推断分析发现低温下以小角度散射占主导地位.     

高光洁度玻璃基片的表面散射和体散射测量

 提出了一种利用总积分散射（TIS）测量K9玻璃基片表面散射和体散射的实验方法。首先采用磁控溅射技术在基片表面沉积厚度为几十nm的金属Ag薄膜，然后将基片的表面和体区分开考虑，通过TIS测得了基片上下表面的均方根粗糙度， 进而求得基片的总散射和表面散射，最后计算得到了体散射。分别利用TIS和原子力显微镜（AFM）测量了3个样品上表面所镀Ag膜的均方根粗糙度，两种方法所得的均方根粗糙度的数值相差不明显，差值分别为0.08，0.11和0.09 nm, 表明TIS和AFM的测量结果相一致。利用该方法测得3块K9玻璃基片的总散射分别为6.06×10^-4，5.84×10^-4和6.48×10^-4，表面散射介于1.25×10^-4~1.56×10^-4之间，由此计算得到的体散射分别为3.10×10^-4，3.30×10^-4和3.61×10^-4。     

HIRFL-CSR 实验环电子冷却装置参数优化

 以400MeV/u的²³⁸U⁹¹为例,用电子冷却模拟程序计算了冷却时间随冷却段长度、冷却段磁感应强度、磁场平行度、电子密度、电子束半径、电子温度的变化规律,并分析了影响冷却时间的因素,获得了电子冷却装置最优参数。     

组合式片状放大器热恢复模拟研究

 针对组合式片状放大器工作时的热量沉积特性,分析了氙灯箱和片腔的冷却过程,重点研究了激光介质钕玻璃片的热恢复过程。初步的热分析表明,为每支氙灯提供4.7×10^-3m³/s的冷却气量以及为每个片腔提供7.6×10^-3m³/s的冷却气量时能够满足装置4小时一发的运行频率要求。     

HIRFL—CSR实验环电子冷却装置调试

HIRFL-CSR实验环电子冷却装置采用了能够产生空心电子束的电子枪。弯曲螺线管内采用了静电偏转电极，冷却段采用了独立的高精度螺线管串联产生纵向磁场的设计。测量了沿离子束运动方向冷却段磁场分布及磁场平行度、电子枪和收集器性能、300kV高压电源相关参数。结果表明，此装置达到了预期的设计目标。: In CSRe electron cooling device， a special electron gun which can produce variable profile electron beam with different size and density distribution was adopted for decreasing ion losses. Electrostatic bending device was used for reducing electron beam losses and improving vacuum condition. The instability of the electron beam is suppressed because the secondary electrons from collector would come back to the collector in the same orbit finally. Longitudinal magnetic field with parallelism better than 10-4 was achieved by adopting of independent high precise solenoid coils at cooling section. In this case， the r.m.s deviations of the transverse magnetic field at cooling section in horizontal and vertical direction are 3.298×10-5 and 2.458×10-5 respectively. The characters of the gun and collector were investigated. The results were presented and indicate that it achieves the design purpose very well.     

螺线管磁场缺陷对电子束横向温度的影响

分析了直螺线管磁场缺陷的来源,考虑了电子束的空间电荷作用,采用数值方法模拟计算了磁场缺陷对电子束横向温度的影响 ,获得了电子冷却装置中直螺线管磁场的均匀性要求.结果表明,当相对磁场缺陷小于1× 1 0-3时 ,影响可以被忽略.In order to obtain the tolerance requirement for the magnetic field homogeneity of the solenoids in electron cooling device, the source of the magnetic imperfection and its influence on the transverse temperature of electron beam were investigated by means of numerical simulation, and taking the space charge effect of electron beam into account. The calculated result shows that the influence of the imperfection of magnetic field will be negligible when the relative magnetic field...     

Effects of downstream magnetic field collimation on ion behavior inelectron cyclotron resonance microwave plasma

Effects of a magnetic held collimation on ion behavior in the downstream region of an electron cyclotron resonance (ECR) plasma device are clarified experimentally using a directional ion energy analyzer. The drift energy and its spread of the ion beam observed in the downstream region decrease and the beam temperature increases with the collimating magnetic flux density. Then, the ion temperature measured perpendicular to the axis of the plasma stream slightly decreases. The ion beam is found to be almost parallel to the magnetic field lines, that is, the beam tends to be collimated     

CSR电子冷却系统强流电子束包络的振荡特性

 HIRFL CSR的电子冷却系统是采用强流电子束对重离子束进行冷却。在冷却段漂移管区，由于强流电子束自身的空间电荷场和螺线管磁场的作用，使得电子束的包络发生振荡。通过求解电子束的横向包络方程，研究了强流电子束包络随电子束参数和螺线管聚焦磁场的变化关系。计算结果表明：对于不同的电子束能量和磁场，电子束包络的振荡频率也不相同；在相同的条件下，磁场越强，电子束包络振荡幅度越小，电子束能量越大，其包络的振荡频率也越快。     

电子束在弯曲螺线管中的运动

 为研究HIRFL-CSR电子冷却装置中电子束穿过电子冷却装置中弯曲螺线管后电子横向能量的变化,用POISSON程序计算出弯曲螺线管的磁场分布,考虑了空间电荷效应,用数值方法模拟计算了电子在弯曲螺线管中的运动情况,得到了电子束横向能量变化最小时磁场各分量与电子束能量和弯曲螺线管几何尺寸之间的关系,并获得了电子束横向能量在束流截面的空间分布。     

Features of cooling dynamics in a high-voltage electron cooling system of the COSY

An electron cooler designed at the Budker Institute of Nuclear Physics for the Cooler Synchrotron COSY (Juelich, Germany) has been put into operation. The aim of this cooling device is to prevent the beam scattering on an internal target up to the maximal energy of the transmitted beam. The device provides cooling in a strong longitudinal magnetic field generated in a high-voltage area. The motion of electrons in the magnetic field considerably improves the kinetics of electron—ion collisions, because their transverse velocity component (which is very high as a rule) does not participate in the process. First experiments on electron beam cooling on energy 200 MeV were made in 2013. Early in 2014, sessions on electron beam cooling to 200, 350, 580, and 1660 MeV were carried out. In other experiments, deuterium beams were cooled down. Experimental data for the cooling time are compared with the respective theoretical predictions. These results may be used in cooling projects for the Nuclotron-based Ion Collider fAcility (NICA), Joint Institute for Nuclear Research, Dubna, Russia, and the Facility for Antiproton and Ion Research (FAIR), Darmstadt, Germany.     

Magnetization reversal observed by the deflection of magnetic actuator

A magnetic actuator consisting of a silicon oxide microcantilever and a silicon oxide plate deposited on ferromagnetic multilayer thin films is fabricated using electron beam lithography and electron beam evaporation, and placed in various magnetic fields to observe its flexure. The magnetic actuator is bent by magnetic torque produced by ferromagnetic multilayer thin films under an external magnetic field owing to the fabrication of a highly sensitive microcantilever and the design of elliptic ferromagnetic thin films with high magnetic shape anisotropy. The magnetic actuator is placed in four kinds of magnetic field directions to investigate the diversity of deflections; the angles between the easy axis of the ferromagnetic multilayer thin films and the direction of the external magnetic field are 90°, 70°, 45° and 20°.     

金属中逆法拉第效应的经典理论

研究电子在圆偏振光驱动下的经典动力学问题以及金属中逆法拉第效应(IFE)的经典微观机制.得到电子在圆偏振光驱动下的一个解,表明其运动轨道是螺旋线.忽略电子与磁场的相互作用,电子作绕平行于其初速度的轴、横截面为椭圆的螺旋线运动,产生了一个平行于其初速度、方向由圆偏振光的手征性决定的磁矩.磁矩的统计结果与Hertel从电子气整体出发得到的结果一致.