Institutional Repository of Institute of Modern Physics, CAS
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DESIGN STUDY OF COMPACT CYCLOTRON FOR INJECTION K=100 SSC*
No full textThe Compact cyclotron was designed for injection of<br />K=100 Separated-Sector-Cyclotron (SSC) [1]. It has four<br />magnet sectors with pancake type and maximum<br />magnetic field is 1.92T. The magnet adopting 4 harmonics<br />has three kinds of holes for beam injection, vacuum<br />pumps and RF systems. The pole diameter was chosen<br />about 80 cm with 50kV dee-voltage and 40°dee-angles.<br />The Injection system of this accelerator consists of a<br />double gap buncher, Solenoid-Qaudrupole-Qaudrupole<br />(SQQ) and a spiral inflector. It will provide a 4~8 MeV,<br />~1 mA of proton beams and 2~4 MeV, ~0.5mA of<br />deuteron ion beam. In this paper we will describe the<br />conceptual design of this machine including the design of<br />Ion-source, Injection system, Magnet and RF system.IMP;Chinese Academy of Science
NEW MAGNETIC EINZEL LENS AND ITS BEAM OPTICAL FEATURES
No full textto focus and transport low energy beam. It is well known<br />that focusing power of a magnetic solenoid lens depends<br />on the ratio of particle momentum and electric charge. A<br />solenoid rotates also an ion beam while focusing it and<br />the phase space areas of the beam in x- and y-plane get<br />entangled and increased. The paper reported here<br />describes an effort to design a new magnetic einzel lens<br />(MEL) using a pair of Glaser solenoid lens (GSL) in antisolenoid<br />mode for the first time to get zero rotation of the<br />exit beam. Analytical formulae have been generated to<br />deduce the scalar magnetic potential and field along the<br />central axis of the lens. Thereafter, beam optics and<br />particle tracking is done using the combined field of a<br />pair of GSL’s constituting the MEL. The required<br />focusing power of the designed lens is achieved for a<br />beam of given rigidity.IMP;Chinese Academy of Science
ANALYSIS OF BEAM QUALITY OPTIMIZATION OF BUCKET ION SOURCE
No full textThe bucket ion source is widely used as the high energy<br />beam source on the high power neutral beam injector<br />system. A hot cathode bucket ion source is studied. The<br />main parameters which influence the performance of<br />bucket ion source are arc voltage, filament voltage, gas<br />inlet rate and extracted voltage. The proton ratio is the<br />dominate parameter for the ion source. In the experiment,<br />the characteristics of ion source are got by regulate the<br />parameter setting. Based on this, the beam proton ratio,<br />are analyzed and optimized. The proton ratio of extracted<br />beam increased from 28 % to 40 %. It is very useful for<br />the experimental operation and study about the bucket ion<br />source.IMP;Chinese Academy of Science
TRIUMF CYCLOTRON BOOSTER FREQUENCY TUNING SYSTEM
No full textFor the auto frequency tuning of TRIUMF cyclotron<br />booster, a new control module based on the VXI Bus has<br />been designed, tested, and put into commission. This new<br />auto tuning control module, which replaced the old<br />analogue control box, has more features, including the<br />implementation of PIC16C71 microprocessor to generate<br />Pulse Width Modulation (PWM) pulse, the utilization of<br />digital RF phase detector, and the most important aspect<br />of computer control capability. Thus, the resonant<br />frequency of the cyclotron booster RF cavity is tuned<br />automatically by this control module, and the reflected RF<br />power is kept at the minimum level in the operation.IMP;Chinese Academy of Science
REVIEW OF CYCLOTRONS USED IN THE PRODUCTION OF RADIO-RADIOISOTOPES FOR BIOMEDICAL APPLICATIONS
No full textAbstract
Cyclotrons are the primary tool for producing the
shorter-lived proton-rich radio-isotopes currently used in
the biosciences. Although the primary use of the cyclotron
produced short-lived radio-isotopes is in PET/CT and
SPECT diagnostic medical procedures, cyclotrons are
also producing longer-lived isotopes for therapeutic procedures.
Commercial suppliers are responding by providing
a range of cyclotrons in the energy range of 3 to 70
MeV. The cyclotrons generally have multiple beams servicing
multiple targets. This paper provides a comparison
of some of the capabilities of the various current cyclotrons.
The use of nuclear medicine and the number of
cyclotrons providing the needed isotopes is increasing. In
the future it is expected that there will be a new generation
of small 'table top' cyclotrons providing patient doses
on demand.IMP;Chinese Academy of Science
STUDY OF MAGNETIC FIELD IMPERFECTIONS OF KOLKATA SUPERCONDUCTING CYCLOTRON
No full textAnalysis of the magnetic data obtained during the
magnetic field mapping of Kolkata superconducting
cyclotron showed imperfections in the main magnetic
field. Since the main magnet of the superconducting
cyclotron is three fold rotationally symmetric, any
deviation from this symmetry creates imperfections in
the magnetic field. Generally, 1st and 2nd harmonic
components are inherently present in the field due to
assembling errors in iron/coil. A major portion of these
imperfections is attributed to the misplacement/tilting of
the iron pole tip with respect to coil. The error in
positioning of main superconducting coil with respect to
surrounding iron produces another imperfection. Pole tip
deformation due to rise of temperature produces field
imperfection. This paper reports the various possible
sources of imperfection in general and their estimation.
The calculation was compared with measured data to
find out the actual cause of imperfections and necessary
corrections have been carried out.IMP;Chinese Academy of Science
INDUCTION SECTOR CYCLOTRON FOR CLUSTER IONS
No full textheavy cluster ions, called “Induction Sector
Cyclotron (ISC)”, is described [1]. Its key feature is
repeated induction acceleration of a barrier trapped ion
bunch. The induction cell (transformer) is energized by
the corresponding switching power supply, which is
controlled by gate signals manipulated from the
circulating beam signal of an ion bunch. The acceleration
synchronizing with the revolution of any ion beam is
always assured. A cluster ion beam such as C-60 [2] can
be accelerated from an extremely low velocity to a nearly
light velocity. Its fundamental concept including required
key devices is described.IMP;Chinese Academy of Science
RELIABLE PRODUCTION OF MULTIPLE HIGH INTENSITY BEAMS WITH THE 500 MEV TRIUMF CYCLOTRON
No full textIn 2001, after 25 years of smooth cyclotron operation
with up to 200 μAH− acceleration, developments towards
higher intensities became compelling because of the ISAC
expansion. Recently the goal of reliable total proton production
current up to 300 μA, within a nominal∼90% duty
cycle, was routinely achieved. Beam availability was 90-
94% over the last five years. Development highlights are
discussed in the paperIMP;Chinese Academy of Science
电离辐射中的非靶效应研究进展
No full text随着电离辐射越来越多地应用于肿瘤治疗及诱变育种,其造成的各种不利影响也逐渐引起人们关注。近年来电离辐射引起的非靶效应成为放射生物学领域的研究热点。对非靶效应三种类型(染色体组不稳定、旁观者效应及适应性反应)及作用机制进行了综述
低β四分之一波长腔中的束流偏转的分析性研究(英文)；Analytical Study on Beam Steering in Low-β Superconducting Quarter Wave Resonators
No full text目前加速速度范围在0.01c—0.3c的粒子的超导腔主要使用四分之一波长腔型。用于不同加速器上的频率范围在50—240MHz的四分之一波长腔在建造或者预研中。这种腔型的一个不足是其横向电磁成分会造成束流偏转效应,从而导致发射度的增长和束流的溢漏,在强流重离子加速器中这种效应尤为严重。对中国科学院近代物理研究所超导直线加速器中的频率为80.5和161MHz的四分之一波长腔的偏转效应进行了分析,计算结果表明,在四分之一腔体的设计时需要考虑到束流偏转的修正,这通常需要在漂移管端面上削适当大小的倾角来实现