Institutional Repository of Institute of Modern Physics, CAS
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GANIL OPERATION STATUS AND DEVELOPMENTS
No full textThe GANIL (Grand Accélérateur National d’Ions<br />Lourds) produces and accelerates stable ions beams since<br />1982. The first radioactive beam post-accelerated with the<br />CIME cyclotron happened in 2001. In 2013, stable beams<br />with higher intensities and new energy range will be<br />available from the new superconducting linear accelerator<br />SPIRAL2. In 2014, new exotic beams will be accelerated<br />with the existing cyclotron CIME. This paper will show<br />how GANIL facility is preparing the arrival of SPIRAL2<br />accelerator. To achieve this goal two main objectives have<br />to been set:<br />• Continuing the delivery of high intensity and exotic<br />beams.<br />• Pursuing the developments of the machine<br />capabilities in a project structure in order to keep<br />equipments running with a high reliability yield and<br />still responding to physics demands.<br />The progress in ion source production (both beam<br />intensities and new species) will be presented together<br />with the foreseen GANIL beam delivery capabilities when<br />SPIRAL2 will be in operation
APPLICATION OF CYCLOTRONS IN BRACHYTHERAPY
No full textCyclotrons are particle accelerator machines which have<br />many applications in industry, technology and medicine.<br />Cyclotrons play an important role in medicine and about<br />50% of the all particle accelerators running in the world are<br />used in medicine for radiation therapy, medical<br />radioisotopes production, and biomedical research. In this<br />short review the use of cyclotrons for a radiation therapy<br />method, brachytherapy, is discussed.<br />Brachytherapy is a form of radiotherapy where a<br />radioactive source placed on or in the tissue to be irradiated.<br />For a long period the production of radioactive isotopes for<br />medical applications was essentially done in nuclear<br />reactors but due to some advantages of radioisotopes<br />production with cyclotron over a nuclear reactor, in the last<br />two decades several types of cyclotrons have been<br />developed to meet the specific demands of radionuclide<br />production.<br />This talk will briefly explain the technical design, beam<br />transfer and beam delivery systems of cyclotron for<br />brachytherapy radioisotope production; and also will shortly<br />describe some detail of 103Pd production in the following:<br />production, targetry, radiochemical separation and seed<br />fabrication
NEW HIGH INTENSITY COMPACT NEGATIVE HYDROGEN ION CYCLOTRONS
No full textBest Cyclotron Systems Inc (BCSI) has been<br />established in Springfield, Virginia, US, for the design<br />and production of commercial cyclotrons. The company<br />is a subsidiary of Best Medical International renowned in<br />the field of medical instrumentation and radiation therapy.<br />Cyclotrons are manufactured and tested at Best<br />Theratronics, Ottawa. BCSI is initially focusing on three<br />different energy cyclotrons 14, 35 and 70MeV negative<br />hydrogen ion accelerators.IMP;Chinese Academy of Science
THE INJECTION LINE AND CENTRAL REGION DESIGN OF CYCIAE-70*
No full textA 70MeV compact cyclotron is under design at CIAE,<br />which is aimed to provide both proton and deuteron by<br />stripping two electrons from H– beam and D– beam<br />respectively. Both of the negative charged beams are<br />produced in a single external multi-cusp ion source,<br />injected axially by a low energy beam injection line and<br />bent onto the median plane through a spiral inflector. In<br />the central region, the electrode structures and the shape<br />of Dee tips are constructed and optimized to achieve<br />matching at the inflector exit and to maximize the<br />acceptance of the central region. The preliminary design<br />results of the injection line, the spiral inflector and the<br />central region are elaborated in the paper.IMP;Chinese Academy of Science
DESIGN OPTIMIZATION OF THE SPIRAL INFLECTOR FOR A HIGH CURRENT COMPACT CYCLOTRON
No full textThis paper describes the design of a spiral inflector in<br />an environment where magnetic field is not constant in<br />the region occupied by it and results of studies done on its<br />optical properties in the presence of space charge. We<br />have used the magnetic field data obtained from a 3D<br />code and analytical electric field. We have also checked<br />the orbit centering of the injected beam using a central<br />region code. The effects of linear space charge have been<br />evaluated and optimization of the input beam parameters<br />has been done to minimize the coupling effects.IMP;Chinese Academy of Science
DETERMINATION OF ISOCHRONOUS FIELD USING CALCULATED MAP OF MAGNETIC FIELD IN CYCLOTRON MEDIAN PLANE
No full textIn this work a new scheme for calculation of a<br />cyclotron isochronous field using the previously<br />calculated or measured map of the cyclotron magnetic<br />field in its median plane is adduced. The calculating map<br />of the cyclotron magnetic field was set by the matrix<br />having the dimensions 201×181. The flutter part of the<br />magnetic field obtained by subtraction of the zero<br />azimuth harmonic from the magnetic field values was<br />calculated in all net nodes. The magnetic rigidity value in<br />the equation for the particle radius versus the angle was<br />replaced by product of the mean radius and mean along<br />the closed orbit magnetic field. The flutter function was<br />interpolated with the help of the third order Lagrange’s<br />polynomials using 16 nodes of the net. At every given<br />radius with the help of the nonlinear simplex method of<br />optimization one can find such value of the isochronous<br />field when the particle path is enclosed with accuracy of<br />10-9. The results of the fulfilled calculations for the<br />cyclotron DC-110 and their comparison with results of<br />other calculations are given.IMP;Chinese Academy of Science
FAST SCANNING TECHNIQUES FOR CANCER THERAPY WITH HADRONS – A DOMAIN OF CYCLOTRONS
No full textIn protontherapy fast 3D pencil beam scanning is
regarded as the most optimal dose delivery method. The
requirements to apply this treatment technique and to
obtain the maximum possible benefit have a big impact
on the accelerator concept. Routinely a very stable,
reproducible and adjustable beam intensity is needed,
which can be set at a few percent accuracy within a
millisecond. Quick changes of maximum intensity from
the cyclotron are also needed when changing treatment
room. Rescanning the tumour volume at high speed to
prevent motion artefacts, needs beam energy variations
within 50-80 ms.
It will be shown that a cyclotron offers the most
advantageous possibilities to achieve this ambitious
performanceIMP;Chinese Academy of Science
BEAM EXTRACTION SYSTEM AND EXTERNAL BEAM LINE OF KOLKATA SUPERCONDUCTING CYCLOTRON
No full textAll the major components of the extraction system of
the Kolkata superconducting cyclotron are installed and
functional. It includes the Electrostatic deflectors,
magnetic channels, M9 slit etc. Internal beam acceleration
has already been done successfully and now we are on the
verge of extracting and transporting the beam to the cave.
The external beam transport system has been designed
comprising of quadrupole magnets, steering magnets,
switching magnets, beam diagnostics etc.
One of the four beam lines has been installed, which
extends 20 meters up to the experimental cave-1. Control
and monitoring system for all these components have
been developed and tested. All the beam dynamical and
technical aspects of the beam extraction and beam
transportation have been discussed.IMP;Chinese Academy of Science
重离子辐照制备电池用微孔膜及其阻抗性质；Preparation of Microporous Membranes by Swift Heavy Ion Irradiation and Impedance Characterization
No full text利用离子辐照结合径迹蚀刻方法制备聚丙烯(PP)微孔膜.用加速器产生的单核能为11.4MeV·u-1(总能量2245.8MeV)的197Au离子束辐照PP膜,剂量为1×108ions·cm-2.辐照后PP膜沿离子路径产生损伤区域,用硫酸与重铬酸钾的混合液进行蚀刻(5-30min),制备出孔径为380-1610nm的聚丙烯微孔膜.对膜的表面和断面形貌进行表征,微孔膜的孔径大小及空间分布均匀,孔道上下贯通,形状近似为圆柱形.给出了微孔膜的孔隙率理论公式.将制备的聚丙烯微孔膜用作锂离子电池隔膜,用电化学阻抗谱(EIS)测定浸满电解液的微孔膜的离子电导率,并与商用隔膜进行比较.分析表明辐照剂量和孔径大小均会影响膜的孔隙率和离子电导率,选择合适的辐照剂量和蚀刻时间,可以制备出孔隙率和离子电导率符合应用标准的聚丙烯微孔膜
小肠电离辐射损伤研究进展；Advances in Small Intestinal Ionizing Radiation Injury Research
No full text肠道的电离辐射损伤是腹部及盆腔肿瘤放射治疗过程中的剂量限制因素。综述了小肠电离辐射损伤的临床症状、小肠上皮及粘膜下层基质改变、信号分子表达变化、组织学变化和超微结构变化。简介了中国科学院近代物理研究所重离子束辐射生物医学重点实验室正在进行的有关小肠重离子辐射损伤及防护方面的研究工作