An integrating current transformer for fast extraction from the HIRFL-CSR main ring

For any experiment that uses the beam of an accelerator, monitoring the beam intensity is always an important concern. It is particularly useful if one can continuously measure the beam current without disturbing the beam. We report here on test experiments for an Integrating Current Transformer （ICT） used to measure fast extraction beams from the HIRFL-CSR main ring （CSRm）. The laboratory tests and beam intensity measurement results are presented in this paper. The influence of the kicker noise is also analyzed.     

An untuned MA-loaded cavity for HIRFL-CSR

In order to realize high energy density physics and plasma physics research at HIRFL-CSR, a magnetic alloy （MA）-loaded cavity has been studied. According to the theoretical calculation and simulation for the MA-loaded cavity, we achieved a better result. The MA-loaded cavity had a higher μQf value, with a higher shunt impedance and a higher accelerating gradient. The accelerating gradient was about 95 kV/m at 1.8003 MHz, 130 kV/m at 0.9000 MHz. Compared with the ferrite-loaded cavities that are used at HIRFL-CSR, with about 10 kV/m accelerating gradient, the MA-loaded cavity obviously has an advantage. The results of the theoretical calculation and the simulation, which meet the design requirements are in good agreement.     

HIRFL-CSR commissioning in 2006 and 2007

HIRFL-CSR, a new heavy ion cooler-storage-ring system at IMP, had been in commissioning since the beginning of 2006. In the two years of 2006 and 2007 the CSR commissioning was finished, including the stripping injection (STI), electron-cooling with hollow electron beam, C-beam stacking with the combination of STI and e-cooling, the wide energy-range synchrotron ramping from 7 MeV/u to 1000 MeV/u by changing the RF harmonic-number at mid-energy, the multiple multi-turn injection (MMI), the beam accumulation with MMI and e-cooling for heavy-ion beams of Ar, Kr and Xe, the fast extraction from CSRm and single-turn injection to CSRe, beam stacking in CSRe and the RIBs mass-spectrometer test with the isochronous mode in CSRe by using the time-of-flight method.     

R-S码快速译码算法的研究

基于ＧＦ（２ｍ ）域的傅里叶变换和傅里叶反变换,提出了Ｒｅｅｄ－Ｓｏｌｏｍ ｏｎ（Ｒ－Ｓ）系统码的一种变换域译码算法,并用Ｃ语言予以实现．与常规Ｒ－Ｓ译码算法相比,该算法运算规范,具有不用求错误多项式的根和错误值、硬件开销小、吞吐率高等优点,适合超大规模集成电路的实现．     

兰州重离子加速器冷却存储环控制系统

为了完成建设兰州重离子加速器冷却存储环,自主研发设计了其大型分布式控制系统。控制系统从功能上分为三层：业务管理层、前端控制层以及设备控制层。业务管理层主要包含控制管理程序、中心数据库以及同步时间系统;前端控制层主要包含前端服务器、前端控制器以及各其他控制器等;设备控制层主要为微控制单元 (MCU)多功能控制器以及被控设备等。其中中央数据库存储整个加速器的所有控制数据,为变能时控制系统的控制数据切换提供数据支持。从长期运行情况来看,控制系统需要进行相应的改进,但是能基本满足现行的实验需求。     

HIRFL－CSR电子冷却装置上的横向电子束温度

从磁场中单电子的轨道运动方程出发，分析并推出了ＨＩＲＦＬ－ＣＳＲ电子冷却装置上的横向电子束温度，并得到了一些重要结论．     

Beam dynamics simulation of HEBT for the SSC-linac injector

The SSC-linac (a new injector for the Separated Sector Cyclotron) is being designed in the HIRFL (Heavy Ion Research Facility in Lanzhou) system to accelerate ²³⁸U³⁴⁺ from 3.72 keV/u to 1.008 MeV/u. As a part of the SSC-linac injector, the HEBT (high energy beam transport) has been designed by using the TRACE-3D code and simulated by the 3D PIC (particle-in-cell) Track code. The total length of the HEBT is about 12 meters and a beam line of about 6 meters are shared with the exiting beam line of the HIRFL system. The simulation results show that the particles can be delivered efficiently in the HEBT and the particles at the exit of the HEBT well match the acceptance of the SSC for further acceleration. The dispersion is eliminated absolutely in the HEBT. The space-charge effect calculated by the Track code is inconspicuous. According to the simulation, more than 60 percent of the particles from the ion source can be transported into the acceptance of the SSC.     

平面激光诱导荧光技术在交错电极介质阻挡放电等离子体研究中的初步应用

利用平面激光诱导荧光技术对交错电极介质阻挡放电过程中产生的痕量组分NO进行了检测. 通过数值模拟对实验结果进行了分析说明,并对介质阻挡放电等离子体流动控制原理进行了简要分析. 此外还通过平面激光诱导荧光技术对等离子体诱导流动进行了直观显示. 关键词： 平面激光诱导荧光 等离子体 介质阻挡放电     

四例基于1, 4-双(3-/4-吡啶基)-2, 3-二氮杂-1, 3-丁二烯的配位聚合物的组装和性质:金属离子对结构的影响

通过水热合成法,合成了4例由混合配体构筑的的过渡金属配位聚合物:{[Zn(4-bpdb)(pnba)₂]·4H₂O}_n(1),[Cd(4-bpdb)(pnba)₂]_n(2),{[Cd₂(3-bpdb)₂(OAc)₄]·5H₂O}_n(3),和{[Co(3-bpdb)(pnba)₂(H₂O)₂]·2H₂O}_n(4)(4-bpdb=1,4-双(4-吡啶基)-2,3-二氮杂-1,3-丁二烯,3-bpdb=1,4-双(3-吡啶基)-2,3-二氮杂-1,3-丁二烯,Hpnba=对硝基苯甲酸,HOAc=乙酸),并且分别用X-射线单晶衍射、元素分析、红外光谱、热差分析、X-射线粉末衍射表征了这4个配合物。晶体结构分析表明,配合物1显示出一维锯齿形链状结构,金属锌(Ⅱ)离子具有稍微变形的四面体配位几何构型。而配合物2和3却展现出一维梯状双链结构,镉(Ⅱ)离子展现出五角双锥几何构型。而配合物4却拥有一维直线型链状结构,其中钴(Ⅱ)离子拥有八面体几何形状。上述结果说明,金属离子的几何构型可能对配合物的结构具有重要的影响。此外,还研究了配合物1~3的荧光性质。