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1.
兰州重离子治癌研究装置的准直测量技术   总被引:1,自引:1,他引:0  
介绍了中国科学院近代物理研究所重离子治癌装置的安装定位测量技术和方法。利用激光跟踪仪通过控制网的建立,和多重坐标系的转换,使最后的磁铁安装径向相对误差不超过±(0.05-0.1)mm,真空管道的横向及竖向精度也达到了±(0.1-0.2)mm。  相似文献   

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The ISOLDE isotope separator facility at CERN provides a variety of radioactive ion beams, currently more than 800 different isotopes from ∼70 chemical elements. The radioisotopes are produced on-line by nuclear reactions from a 1.4 GeV proton beam with various types of targets, outdiffusion of the reaction products and, if possible, chemically selective ionisation, followed by 60 kV acceleration and mass separation. While ISOLDE is mainly used for nuclear and atomic physics studies, applications in materials science and biophysics account for a significant part (currently ∼15%) of the delivered beam time, requested by 18 different experiments. The ISOLDE materials science and biophysics community currently consists of ∼80 scientists from more than 40 participating institutes and 21 countries. In the field of materials science, investigations focus on the study of semiconductors and oxides, with the recent additions of nanoparticles and metals, while the biophysics studies address the toxicity of metal ions in biological systems. The characterisation methods used are typical radioactive probe techniques such as Mössbauer spectroscopy, perturbed angular correlation, emission channeling, and tracer diffusion studies. In addition to these “classic” methods of nuclear solid state physics, also standard semiconductor analysis techniques such as photoluminescence or deep level transient spectroscopy profit from the application of radioactive isotopes, which helps them to overcome their chemical “blindness” since the nuclear half life of radioisotopes provides a signal that changes in time with characteristic exponential decay or saturation curves. In this presentation an overview will be given on the recent research activities in materials science and biophysics at ISOLDE, presenting some of the highlights during the last five years, together with a short outlook on the new developments under way.  相似文献   

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The present-day situation and prospects for the development of electron beam ion sources are considered and associated investigations of the physics of highly ionised atoms at JINR Primary consideration is given to experiments based on measurements of X-ray spectra.Specific features of the experiment include statements of QED in strong fields using electron beam ion sources.  相似文献   

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To study the fast intracellular calcium response after ion irradiation in living mammalian cells, a live cell calcium imaging set-up was constructed at the targeted cell irradiation facility at GSI. This work introduces the live cell calcium imaging system, shows its performance, an example of the ratio-metric calcium measurement and its application to on-line study calcium response to targeted ion irradiation in human cells.  相似文献   

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ECR(电子回旋共振)离子源是产生稳定的强流多电荷态离子束流最有效装置.全永磁ECR离子源因其独特的特点为很多中小型多电荷态离子束流实验平台与离子注入机等系统所采用,为后者产生重复性好、稳定性强的多电荷态离子束流.本文着重论述了中国科学院近代物理研究所研制的几台全永磁多电荷态ECR离子源及其特性与典型性能,如能产生强流高电荷态离子束流的高性能全永磁离子源LAPECR2,能产生强流中低电荷态离子束流的LAPECR1,能产生多电荷态重金属离子柬流的LAPECRl-M等.这些性能稳定的离子源为提高近代物理研究所相关试验平台的性能提供了关键的束流品质保障.  相似文献   

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The operational TISOL thick target, on-line isotope separator at the TRIUMF, 500 MeV proton cyclotron facility has been upgraded to be a production facility with an active experimental program. A new experimental area is now available and modifications are under design to handle remotely the expected radioactively “hot” targets. Two ion source systems are now available, a heated surface of normal design and a new ECR (electron cyclotron resonance) source resulting in ion beams from a wide range of elements. Details of the new upgraded facility will be presented along with its experimental program and plans for the future. The status of the previously proposed accelerated radioactive beams facility, ISAC, for which TISOL is a prototype front-end system, will also be mentioned.  相似文献   

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Various 2.45 GHz microwave electron cyclotron resonance (ECR) ion-sources designed with quartz tubes and without hexapole have been developed and tested for production, transport and focalization of singly-charged ions. A first on-line endeavour to separate radioactive isotopes in a He-jet coupled mode has been realized with a capillary skimmer ion-source injection system parallel to the source plasma axis. In order to improve the coupling of a ECR source with the He-jet system, a new compact metallic body ion-source with a skimmer-catcher injection arrangement perpendicular to the plasma has been designed. The layout of this new metallic ion-source is given. The ionization efficiencies have been measured as a function of gas pressure for a complete off-line regime with various support gases and for a dynamical regime induced with an He-jet injection simulating the subsequent on-line coupled mode conditions.  相似文献   

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The aim of this project is to develop a new system for single ion irradiation of cells for genetic and cell biology studies. This charged particle focused microbeam system will provide a fully computer controlled irradiation facility with submicron (subcellular) resolution and will open many new avenues into studies of radiobiological mechanisms. In the first stage of this project a system for single ion detection has been developed. A thin diamond window has been tested as vacuum/atmosphere window and as a possible source of secondary electrons and/or photons for single ion detection. A detection efficiency of 97% has been achieved.  相似文献   

12.
The ITER neutral beam system is using inductively coupled radio frequency (RF) ion sources, that have demonstrated the required ITER parameters on (small) sources with extraction areas up to 200 cm2. As a next step towards the full size ITER source IPP is presently constructing the test facility ELISE (“Extraction from a Large Ion Source Experiment”) operating with a “half-size” source which has approximately the width but only half the height of the ITER source. The modular driver concept is expected to allow a further extrapolation to the full size in one direction to be made. The main aim of this experiment is to demonstrate the production of a large uniform negative ion beam with ITER relevant parameters in stable conditions up to one hour.Plasma operation of the source is foreseen to be performed continuously for 1 h; extraction and acceleration of negative ions up to 60 kV is only possible in pulsed mode (10 s every 180 s) due to limitations of the existing IPP HV system. The design of the source and extraction system implements a high experimental flexibility and a good diagnostic access while still staying as close as possible to the ITER design. The main differences are the source operating in air and the use of a large gate valve between the source and the target chamber.ELISE is expected to start operation at the end of 2011 and is an important step for the development of the ITER NBI system; the experience gained early will support the design as well as the commissioning and operating phases of the PRIMA NBI test facilities and the ITER neutral beam system.  相似文献   

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In this paper,we report a novel measurement system based on the development of Fudan Scanning Proton Microscopy(SPM) facility.By using Si-PIN diode(Hamamatsu S1223-01) detector,scanning transmission ion microscopy(STIM) measurement system has been set up.It can provide density and structural images with high probing efficiency and non-destruction by utilizing the energy loss of high energy(MeV) and focused ions penetrating through a thin sample.STIM measurement is able to map the density distribution of organic elements which mostly compose biology materials,such information can not be detected by using conventional Be-windowed Si(Li) X-ray detector in Particle Induced X-ray Emission(PIXE) technique.The spatial resolution capability of STIM is higher than PIXE technique at same accelerator status.As a result of STIM measurement,Paramecium attached on the top of Kapton tube was measured by STIM.  相似文献   

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A new ionoluminescence (IL) apparatus has been successfully installed at the external scanning microbeam facility of the 3 MV Tandetron accelerator of the INFN LABEC in Firenze; the apparatus for photon detection has been fully integrated in the existing ion beam analysis (IBA) set-up, for the simultaneous acquisition of IL and PIXE/PIGE/BS spectra and maps.The potential of the new set-up is illustrated in this paper by some results extracted by the analysis of art objects and advanced semiconductor materials. In particular, the adequacy of the new IBA set-up in the field of cultural heritage is pointed out by the coupled PIXE/IL micro-analysis of a lapis lazuli stone; concerning applications in material science, IL spectra from a N doped diamond sample were acquired and compared with CL analyses to evaluate the relevant sensitivities and the effect of ion damage.  相似文献   

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Recent progress of EBIS and ECRIS are described after a brief recall of the characteristics of several important ways of producing highly charged ions.  相似文献   

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We report on an ongoing program of improvements to the National Electrostatics (NEC) MC-SNICS ion source at the KCCAMS laboratory at UC Irvine. Recent work has focused on vacuum improvements and on increasing the source output and efficiency. We replaced the extractor and preacceleration assemblies for a threefold improvement in pumping conductance, leading to lower source pressures and quicker startup after sample wheel changes. A switch to spherical ionizers caused a marked improvement in the focusing of the Cs beam, leading to major gains in ion source efficiency and negative ion beam quality. Better confinement of Cs within the new ionizer assembly resulted in lower Cs consumption and a significant reduction in arcing problems.  相似文献   

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The test facility ELISE which was constructed in the last three years at the Max-Planck-Institut für Plasmaphysik (IPP), Garching, is an important intermediate step of the development of the neutral beam system for ITER. ELISE allows gaining an early experience of the performance and operation of large RF driven sources for negative hydrogen ions and will give an important input for the commissioning and the design of the SPIDER and MITICA test facilities at Padua and the ITER neutral beam system. ELISE has gone recently into operation with first plasma and beam pulses. The experiments aim at the demonstration of an ion beam at the required parameters within 2 years of operation until end of 2014, the end of the service contract with F4E for the establishment and exploitation of ELISE.  相似文献   

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We report on an ongoing program of improvements of the Jena AMS system. The present contribution focuses on the improvement of the High Voltage Engineering Europe (HVEE) ion source 846. Furthermore it is described how the usable current range is determined at the Jena lab.  相似文献   

20.
Parasitic beam tunnel oscillations have been discovered on some of the series production gyrotrons for W7-X and also on the coaxial pre-prototype gyrotron for ITER. Solutions to remedy these problems have resulted in a modified beam tunnel design, technologically close to the existing beam tunnel. The new design has successfully been tested on both the coaxial and also the f-step-tunable gyrotrons and has subsequently been implemented on one of the W7-X series-production-tubes presently undergoing factory acceptance tests in Karlsruhe.The ECRH test loads at KIT are operated under normal atmospheric conditions. Several loads have eventually failed in 1 MW long pulse experiments and KIT has therefore started to design its own loads. The first KIT-load is based on a fixed conical mirror and an aluminum cylinder coated with a lossy material for increased absorption. The new load has so far successfully been used during the acceptance tests of two 1-MW CW gyrotrons. Nevertheless a new load based on pure (uncoated) stainless steel absorbers is being developed as a backup solution for the ongoing high priority gyrotron testing.A superconducting magnet capable of rapid field changes between 4.15 and 5.67 T for frequency step-tunable gyrotrons has been procured, has demonstrated a (static) field of 7.2 T and its capability of rapid field-changes.  相似文献   

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