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1

World trends in cyclotron developments for nuclear physics and applications

100%

Baron E.

Nukleonika

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2003

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tom Vol. 48,suppl.2

3-11

EN

Today, the number of cyclotrons operating in the world largely exceeds 200. The field of uses covers production of radioisotopes for medicine, therapy by neutron and ion beams, nuclear, atomic and solid state physics research, material analysis and radiation damage studies, and production of intense neutron beams for present and future purposes. Despite this diversity, continuing efforts driven by both research laboratories as well as commercial firms result in a series of improvements in the various techniques used in the design and operation of cyclotrons. This paper intends to draw the main directions of evolution in the following issues: injection and extraction systems, beam dynamics (including high intensity issues), magnetic and electric fields computation, as well as existing and possible future applications in medicine, production of energy, neutron spallation sources and transmutation technologies. The question of a possible resurrection of FFAG (Fixed-Field, Alternating Gradient) cyclotrons, a concept invented in the fifties, will be shortly brought up.

2

Ion transport from the source to first cyclotron orbit

100%

Belmont J.

Nukleonika

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2003

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tom Vol. 48,suppl.2

13-20

EN

The ions produced by an external source and axially injected into the cyclotron are considered. The ion beam, with a matching structure, must be carefully placed on the orbit to be accelerated and well extracted. One has to take into account its position on the first turn, its shape, its chopped time structure due to RF (radio-frequency). A compromise between different necessities must be obtained. In fact beam losses can be significant, and the ion transfer efficiency from the source to the orbit varies from a few per cent to 70%!

3

Beam-dynamics studies in a 250 MeV superconducting cyclotron with a particle tracking program

100%

Shippers J. , Vranković V. , George D.

Nukleonika

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2003

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tom Vol. 48,suppl.2

145-147

EN

A 250 MeV superconducting compact cyclotron, based on an original concept from H. Blosser (NSCL) and to be designed and manufactured by ACCEL (D), is being developed for the proton therapy project PROSCAN at PSI. We have used the general purpose three dimensional particle tracking program TRACK, developed at PSI, in the configuration of the 250 MeV cyclotron to perform studies of the beam dynamics and to derive important parameters describing the beam properties. Detailed tracking studies have been performed in the central region and in the extraction region. Examples of our ongoing studies are discussed to demonstrate the capabilities of the program TRACK.

4

Production and quality control of 66Ga radionuclide

80%

Sabet M. , Rowshanfarzad P. , Jalilian A. , Ensaf M. , Rajamand A.

Nukleonika

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2006

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tom Vol. 51, nr 3

147-154

EN

The purpose of this study was to develop the required targetry and radiochemical methods for production of 66Ga, according to its increasing applications in various fields of science. The 66Zn(p,n)66Ga reaction was selected as the best choice for the production of 66Ga. The targets were bombarded with 15 MeV protons from cyclotron (IBA-Cyclone 30) at the Nuclear Research Center for Agriculture and Medicine (NRCAM) with a current of 180 mA for 67 min. ALICE and SRIM (Stopping and Range of Ions in Matter) nuclear codes were used to predict the optimum energy and target thickness. Targets were prepared by electroplating 95.73% enriched 66Zn on a copper backing. Chemical processing was performed by a no-carrier-added method consisting of ion exchange chromatography and liquid-liquid extraction. Anion exchange chromatography was also used for the recovery of target material. Quality control of the product was carried out in two steps of chemical and radionuclide purity control. The activity of 66Ga was 82.12 GBq at EOB and the production yield was 410.6 MBq/mAh. The radiochemical separation yield was 93% and the yield of chemical recovery of the target material was 97%. Quality control tests showed a radionuclide purity higher than 97% and the amounts of chemical impurities were in accordance with the United States Pharmacopoeiae levels.

5

Production, quality control and initial imaging studies of [82mRb]RbCl for PET studies

80%

Rowshanfarzad P. , Jalilian A. , Kiyomarsi M. , Sabet M. , Karimian A. , Moradkhani S. , Mirzaii M.

Nukleonika

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2006

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tom Vol. 51, nr 4

209-215

EN

Rubidium-82m was prepared via 15.4 MeV proton irradiation of a krypton-82 gaseous target (30% enrichment). Washing the target chamber with hot water yielded a Rb-82m containing solution, which was further purified using short column chromatography in order to remove organic/inorganic impurities. The flowthrough was formulated in normal saline for injection. Radionuclide, radiochemical and chemical purity tests were performed prior to administration to rats for imaging (radiochemical yield: 95-97%, radiochemical purity > 97%). Preliminary dual-head coincidence studies were performed to determine the distribution of [82mRb]Rb in normal rats. For biodistribution studies, Rb-81 was injected to rats and tracer accumulation in heart, GI and bladder was determined after sacrification in time intervals. A yield of 1.3 GBq at EOB, 235.7 MBq/mAh was obtained.

6

Magnetic system of the heavy ion cyclotron for track membranes production

80%

Alenitsky Y. , Zaplatin N. , Onischenko L. , Samsonov E. , Chesnov A.

Nukleonika

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2003

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tom Vol. 48,suppl.2

55-57

EN

A heavy ion fixed energy cyclotron based on a conventional magnet with a pole diameter of 1.6 m is designed and constructed in JINR. Ions with A/Z = 5 are accelerated up to the energy E = 2.4 MeV/nucleon. The isochronous magnetic field is formed by four pairs of sector shims. The beam phase shift in formed field is less than š15°RF, and the first harmonic of magnetic field is less than 3 G for all radii of the beam acceleration. Power consumption of magnet is 25 kW. The ECR source with an intensity of 3.5 × 1012 ions/s is used as an ion source. The extracted beam (~1011 ions/s) is intended for the track membrane production.

7

A method of the magnetic field formation in cyclotron DC-72

80%

Gulbekian G. , Ivanenko I. , Filatov O. , Franko J. , Kukhtin V. , Lamzin E. , Samsonov E. , Semchenkov A. , Semchenkova O. , Sytchevsky S. E. , Dmitrev S. N.

Nukleonika

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2003

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tom Vol. 48, nr 4

207-210

EN

A method of the magnetic field formation in the cyclotron DC-72 model (scale 1:5) is described. The cyclotron is planned to be built in Slovakia. The stages in the shimming of the cyclotron sectors and an automatic system designed for magnetic measurements are described. The data on the magnetic field measurements in the median plane of the cyclotron are presented. A brief description of a computer simulation model and an algorithm of fitting the required sector profiles is presented, as well as the data on the computer simulation of magnetic field distributions. The data on the magnetic field measurements and those on the computer simulations are compared and analyzed. Possible reasons of differences between the measured and simulated data are discussed. The results of the above mentioned computer simulations will be used for building a large facility - the cyclotron DC-72.

8

Space charge dominated beam transport in the K130 cyclotron injection line

80%

Heikkinen P.

Nukleonika

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2003

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tom Vol. 48,suppl.2

21-24

EN

High intensity H- beams are injected into the K130 cyclotron [1] for isotope production and for proton induced fission studies. Earlier, when protons were accelerated as positive ions, the beam intensity was limited by beam losses in the extraction system from the cyclotron. Stripping extraction of negative ions removed this limitation. However, now space charge effects in the injection beam line limit the beam intensity. At present, the maximum practical H- beam intensity at the inflector is about 0.25 mA, which gives 40-50 žA of extracted proton beam. Calculations predict that the injection beam line from the ion source to the matching quadrupoles below the cyclotron can transfer about 1 mA of 6 keV H- beam, which also was measured. The quadrupole section has a smaller transmission. Also a significant portion of the beam is lost during the last 2 m in the axial hole. General rules for maximum beam intensity as a function of beam line parameters such as beam tube aperture, distance of focusing elements, beam charge, mass and energy are given for different kinds of focusing systems (solenoids, FODO and FOFDOD quadrupole structures). As a conclusion, some suggestions to improve the transmission of the injection line are given.

9

Development of a magnetic field monitoring system for the JAERI AVF cyclotron

80%

Okumura S. , Arakawa K. , Fukuda M. , Nakamura Y. , Yokota W. , Ishimoto T. , Kurashima S. , Ishibori I. , Nara T. , Agematsu T. , Nakajima T.

Nukleonika

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2003

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tom Vol. 48,suppl.2

35-37

EN

We have developed a probe of a nuclear magnetic resonance (NMR) magnetometer for measurement of a fluctuation of an AVF cyclotron field. The stability of the magnetic field of the JAERI AVF cyclotron, measured with the NMR probe, was within 1 × 10-5. A field-measurement accuracy of the order of 1 × 10-6 was achieved using a set of field-compensation coils and optimizing the probe position to obtain enough homogeneity of the magnetic field around the probe for measuring the cyclotron field with a high gradient. To eliminate a major bottleneck in the field measurement inside the cyclotron, the probe was specially produced with the cable shielding against RF noises and proper materials applied.

10

The IBA self-extracting cyclotron project

80%

Kleeven W. , Lucas S. , Delvaux J. , Swoboda F. , Zaremba S. , Beeckman W. , Vandeplassche D. , Abs M.

Nukleonika

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2003

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tom Vol. 48,suppl.2

59-67

EN

The self-extracting cyclotron is a high-intensity 14 MeV H+ machine for isotope production. There is no electrostatic deflector. Extraction is achieved with a special shaping of the magnetic field. There are two long poles and two short poles, both with an elliptical gap profile; this provides a steep fall off of the magnetic field at the pole radii. An extraction groove is machined in the iron of one of the longer poles. First harmonic coils create a large orbit separation at the entrance of the extraction path and extract the beam. The machine is presently installed in the industrial isotope production site where the final commissioning and tests took place. Beams of more than 1.5 mA have been extracted and transported. Further development is ongoing in order to increase the current on target to at least 2 mA in the coming months. Commercial isotope production will start in the course of this year. The concept of the machine is explained and the layout of the machine and beam lines is presented. Results of orbit calculations and central region optimizations are given. Results of the measurement of extracted beam shapes and emittances are given. The progress and present status of the project are discussed.

11

The radiochemistry cyclotron in University of Helsinki

80%

Helariutta K. , Hakanen M. , Solin O.

Nukleonika

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2003

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tom Vol. 48,suppl.2

173-174

EN

The 10 MeV proton cyclotron in the Laboratory of Radiochemistry, University of Helsinki is presented. Recent activities as well as the future research and teaching directions around the cyclotron are discussed.

12

Compact cyclotrons for the production of tracers and radiopharmaceuticals

80%

Paans A.

Nukleonika

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2003

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tom Vol. 48,suppl.2

169-172

EN

Positron Emission Tomography (PET) is a method for determining biochemical and physiological processes in vivo in a quantitative manner. The most commonly used radionuclides are 11C, 13N, 15O and 18F, with respective half-lives of approximately 20 min, 10 min, 2 min, and 110 min. 18F labeled FDG (fluoro-2-deoxy-D-glucose) is now the most frequently used radiopharmaceutical and finds its application prominently in the field of oncology. Originally, the production of these radionuclides was performed with the existing accelerators, designed for nuclear physics, but with increasing interest in the PET methodology specially designed PET-production cyclotrons became available. The nuclear reactions involved are (p,n), (d,n), (p,a) and (d,a) and the thresholds for the nuclear reactions involved are 5 to 6 MeV. Based on these values and on other parameters, a proton 15 to 20 MeV cyclotron is often chosen. Since the half-life of a radionuclide limits the production time, the maximum beam current is an important parameter, together with the target construction, for the ultimate yield obtainable. In the development of special PET production cyclotrons, attention has also been paid to improve the extraction efficiency and the possibility of multiple extractions by designing negative ion cyclotrons. Commercial cyclotrons can often be acquired as an easy to operate integrated radionuclide production unit including targetry and some units. Regional FDG factories are nowadays being created to fulfil the demand for PET radiopharmaceutics. The possible choices in commercially available cyclotrons for the production of PET radionuclides will be discussed.

13

A Superconducting Cyclotron as a primary accelerator for exotic beam facilities

80%

Maggiore M. , Rifuggiato D. , Calabretta L.

Nukleonika

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2003

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tom Vol. 48,suppl.2

165-167

EN

A four sector compact superconducting cyclotron for light ion beams with a maximum energy of 250 MeV/amu has been studied. This cyclotron is mainly designed to accelerate H2 + ions to be extracted by stripping. Ions like C, O or Ne can also be accelerated and extracted by stripping. Extraction by stripping allows to overcome many problems, especially if a certain beam intensity is requested. The preliminary design model of the magnet circuit has been accomplished with the 3D electromagnetic code OPERA [4]. The design of the main coils and of the cryostat has been investigated, too. The features of beam dynamics of this cyclotron, including extraction trajectories, will be presented. Several fields of application have been envisaged for this cyclotron, namely nuclear physics, therapy treatment, interdisciplinary research and radioisotope production using low or medium intensity beams.

14

Status report of the LNS Superconducting Cyclotron

80%

Rifuggiato D. , Calabretta L. , Cuttone G.

Nukleonika

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2003

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tom Vol. 48,suppl.2

131-134

EN

The LNS Superconducting Cyclotron has been working in stand alone mode since the beginning of 2000, after 5 years of operation as a booster of the 15 MV Tandem. The new mode has proven to be by far more advantageous than the previous one from the point of view of operation. Working with axial injection, a quite high number of new beam types has been developed. The new mode allows for acceleration of H2 + molecules, which break into two protons when crossing a stripper in the beam line out of the cyclotron. 62 MeV protons have been used for radiotherapy since February 2002. The new mode allows to inject a more intense beam as compared to the previous mode. Therefore, an upgrading program of the cyclotron has started, aiming at having an intense extracted beam to be used as a primary beam in a facility for production of radioactive beams. Beam tests have been accomplished to evaluate transmission figures, while the upgrading of the present electrostatic deflectors has started: new deflector systems, able to dissipate high beam power and allowing for easier maintenance, have been designed and will soon be tested in the machine.

15

Simulation of operation modes of isochronous cyclotron by a new interative method

80%

Taraszkiewicz R. , Talach M. , Sulikowski J. , Doruch H. , Norys T. , Sroka A. , Kiyan I.

Nukleonika

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2007

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tom Vol. 52, nr 1

29-34

EN

Operation mode simulation methods are based on selection of trim coil currents in the isochronous cyclotron for formation of the required magnetic field at a certain level of the main coil current. The traditional current selection method is based on finding a solution for all trim coils simultaneously. After setting the calculated operation mode, it is usually necessary to perform a control measurement of the magnetic field map and to repeat the calculation for a more accurate solution. The new current selection method is based on successively finding solutions for each particular trim coil. The trim coils are taken one by one in reverse order from the edge to the center of the isochronous cyclotron. The new operation mode simulation method is based on the new current selection method. The new method, as against the traditional one, includes iterative calculation of the kinetic energy at the extraction radius. A series of experiments on proton beam formation within the range of working acceleration radii at extraction energies from 32 to 59 MeV, which were carried out at the AIC144 multipurpose isochronous cyclotron (designed mainly for the eye melanoma treatment and production of radioisotopes) at the INP PAS (Kraków), showed that the new method makes unnecessary any control measurements of magnetic fields for getting the desired operation mode, which indicates a high accuracy of the calculation.

16

The proton beam energy measurement by a time-of-flight method

80%

Kisieliński M. , Wojtkowska J.

Nukleonika

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2007

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tom Vol. 52, nr 1

3-5

EN

A simple TOF equipment for cyclotron protons beam energy measurement was constructed. For short distance of 165 cm between capacitive pick-up probes, the accuracy of proton beam energy is below 1% for mean beam currents above 200 nA and within the energy range 20 30 MeV.

17

Pomiary pól magnetycznych w cyklotronie izochronicznym AIC-144

80%

Daniel K.

Pomiary Automatyka Robotyka

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2001

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tom R. 5, nr 11

28-30

PL

Przedstawiono sposób wykonania złożonych pomiarów pól magnetycznych wewnątrz komory cyklotronu AIC-144 znajdującego się w Instytucie Fizyki Jądrowej w Krakowie. Szczególny nacisk położono na optymalizację pomiarów, ze względu na ich dużą czasochłonność i związane z tym znaczne koszty.

EN

There are presented the method how to realize the complex measurements of magnetic fields in the AIC-144 cyclotron chamber, situated in the Nuclear Physics Institute in Cracow. The special emphasis is laid on measurement optimatization, due to their time-consuming and high costs.

18

Production and separation of manganese-54 from alpha-irradiated V2O5 target

70%

Kłos M. , Bartyzel M. , Petelenz B.

Nukleonika

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2006

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tom Vol. 51, nr 4

221-224

EN

Our aim was to obtain and isolate the carrier-free gamma emitter, 54Mn. Manganese-54 was produced via cyclotron activation in the 51V(alfa,n)54Mn reaction, and separated from HCl solution on Dowex-50 . 8 resin. The effectiveness of chemical separation was checked using the internal tracer 48V, produced in a cyclotron via the natTi(p,xn)48V reaction. The microcomponent 54Mn was eluted from the column with 3 M HCl, and vanadium with a 0.1 M HCl/ethanol/H2O2 mixture. The pair Ti/48V was separated on Dowex-50 . 8, using 0.03 M HClO4 as the eluent for 48V and 1 M HClO4 for natTi. The carrier-free 54Mn was of 99.9% radionuclide purity. In separation of the carrierfree pair 54Mn/48V, the recovery yield was 98.7% for 54Mn and 96.4% for 48V.

19

Operation of the RFQ-injector at the ISL cyclotron

70%

Pelzer W.

Nukleonika

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2003

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tom Vol. 48,suppl.2

25-28

EN

Since 1999, a new injector for the k132 cyclotron at ISL-Berlin has been operated successfully. The new machine consists of an ECR-source on a high voltage platform and an RFQ accelerator of novel 2-stage-design. Beams are injected radially into the cyclotron at an energy level of 90 to 360 keV per nucleon, at a charge to mass ratio of 1/8 to 1/5. We report on operation experience and hardware improvements.

20

Magnetic field simulation in the central region of the VINCY Cyclotron

70%

Vorojtsov S. , Vorozhtsov A. , Nešković N. , Ristić -Durović J. , Ćirković S. , Vujović V.

Nukleonika

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2003

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tom Vol. 48,suppl.2

39-44

EN

The VINCY Cyclotron is under construction at the Vinca Institute of Nuclear Sciences, Laboratory of Physics, Belgrade, Serbia and Montenegro. One of the most difficult problems to solve is the magnetic field shaping in the central region of the machine in a wide range of field levels. The latest measurements showed a very large magnetic field depression in the central region. The following shimming elements are used for the field shaping in the central region: a central plug and a spacer ring between the sectors and the median pole plate. These elements should both release enough vertical space for the inflector and the RF electrodes and produce a field bump in the very center of the machine. Concerning this region, one has to mention the following facts: sectors are absent or very reduced, and the small gap between the sectors restricts remarkably the possibilities of producing a field bump. Therefore, the design of these elements is the most critical one. Optimization of the central plug gap affects both the vertical sparking probability and the beam dynamics at higher harmonic modes. The redesign of the magnetic structure of the central region relied solely on the detailed 3-dimensional calculations to speed up the experimental shimming procedure. The desired calculated magnetic field shapes, which include the influence of the plug, have been produced and confirmed