IPAC2013 - List of Authors (Zhang, T.J.)

Paper	Title	Page
MOPFI028	Physical Design Progress of an 800 MeV High Power Proton Driver	342
	J.J. Yang, Shizhong. An, M. Li, T.J. Zhang, J.Q. Zhong CIAE, Beijing, People's Republic of China
	We presented the conceptual design of an 800 MeV high power proton ring cyclotron in the paper[1] . A more detailed physical design was carried out since then. The most challenging issues regarding the high power operation, including the space charge effects and beam loss during the extraction, are quantitatively studied by using state-of-the-art high performance computation technique. On that basis the fundamental structure of the cyclotron is adjusted and optimized so as to meet the requirements of MW-class operation. Reference: [1] T. Zhang, J. Yang, M. Li, et. al., Conceptual design of an 800 MeV high power proton driver, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 269(24) (2011) 2964-2967

MOPFI029	The Construction Progress of Beijing Radioactive Ion-beam Facility	345
	T.J. Zhang, Shizhong. An, B.Q. Cui, Z.G. Li, Y.L. Lu, C.H. Peng, F. Yang CIAE, Beijing, People's Republic of China
	The Beijing Radioactive Ion-Beam Facility (BRIF) is being constructed at CIAE. The project consists of a 100 MeV high intensity cyclotron CYCIAE-100, an ISOL system with a mass resolution of 20000, and a superconducting booster. The construction of the building was started on April 28, 2011 and the roof was sealed on Jan. 16, 2012. The on-site installation conditions have been ready since Sept. 27, 2012. Up to now, the fabrication of all major components for CYCIAE-100 have been completed, including the main magnet system, the RF system, ion source and injection, main vacuum, etc. The equipment fabrication for the ISOL system has been completed and magnetic mapping and shimming is being performed on the large-scale analysis magnet. The fabrication of the major components for the superconducting booster has been accomplished, and the work on copper-niobium sputtering is under way. At present, the installation and assembly is in full swing and the beam commissioning is to predicted to be finished in mid 2013. Taking advantage of the experiences accumulated on the CRM cyclotron with beam up to 430 uA, it is likely that the first beams of 100 MeV can be achieved by the end of 2013.

TUPWA011	Investigation of Emittance Growth in a Small PET Cyclotron CYCIAE-14	1745
	M. Li, Shizhong. An, T.J. Zhang CIAE, Beijing, People's Republic of China
	In order to satisfy the rapidly increased domestic needs for PET in China, a small medical cyclotron named CYCIAE-14 is designed and constructed in CIAE ( China Institute of Atomic Energy ) . As the beam intensity in CYCIAE-14 is high, the beam emittance should be controlled strictly in order to reduce the beam loss in the cyclotron. Precessional mixing and resonance crossing are the two main factors leading to emittance growth in the cyclotron with stripping extraction. In this paper, the physical mechanism of precessional mixing in a stripping extraction cyclotron is investigated. After that, the maximum allowable field errors in CYCIAE-14 are derived using the Hamiltonian formalism and numerical simulation, which provides a reference for the cyclotron design and field shimming.

TUPWA012	The Influence of the Magnetic Field Errors in CYCIAE-100 Cyclotron	1748
	H.J. Yao, M. Li, T.J. Zhang, J.Q. Zhong CIAE, Beijing, People's Republic of China
	The main magnet size of CYCIAE-100 is 2.31 m in height and 6.16 m in diameter and the outer radius of the sector is 2.0 m, and the total iron weight is about 415t. The magnetic filed can not be absolutely ideal because of imperfections during manufacturing and installation of this big magnet. Therefore the influence of the magnetic field errors on the beam behavior should be studied to provide the reference for magnet mapping and shimming. Magnetic field errors in a cyclotron will excite coherent oscillations through displacing the center of orbit or distorting the transverse phase space. This effect is especially important in the CYCIAE-100 cyclotron because there are a number of different turns in the extracted beam. The tolerances for the magnetic field errors are given in this paper based on analytic calculations and numerical simulations. The resonances vr=1, 2vr=2 driven by the 1st, 2nd harmonic magnetic field are considered, which will result in the radial emittance growth .Besides that, the resonances cause the vertical emittance growth are considered. The maximum allowable field errors for CYCIAE-100 are presented in this paper.

WEPFI026	Design and Commissioning of the RF System of CYCIAE 14 Cyclotron	2759
	Z.G. Yin, B. Ji, Y. Lei, P.Z. Li, G.F. Song, C. Wang, T.J. Zhang, Z.L. Zhao CIAE, Beijing, People's Republic of China
	The RF system of CYCIAE-14 consists of a set of 20kW amplifier, two 1/4λ RF cavities connected in central region, the transmission line and a set of LLRF system. The LLRF system, based on DDS and DSP, has achieved the close-loop adjustment of accelerating voltage and the resonant frequency. The RF system design for CYCIAE-14 was started in 2010, and the fabrication of the major equipments was finished in 2011. The installation and commissioning was completed in early 2012, satisfying the design requirements. This article describes the design of the RF system, and summarizes the difficulties encountered in the process of manufacture, installation and commissioning. Some of the problems caused by the transmission line and the RF leakage are analyzed, followed by the measures taken to solve these problems.

THPFI018	The Design and Construction of Stripping Probe System for CYCIAE-100	3333
	Shizhong. An, F.P. Guan, P.Z. Li, L.P. Wen, H.D. Xie, Z.G. Yin, T.J. Zhang CIAE, Beijing, People's Republic of China
	A 100 MeV H⁻ compact cyclotron is being constructed in China Institute of Atomic Energy (CYCIAE-100). 75 MeV - 100 MeV proton beams with 200 μA beam intensity will be extracted in dual opposite directions by charge exchange stripping devices. Two stripping probes with carbon foils are inserted radially in the opposite direction from the main magnet pole and the obtained two proton beams after stripping foil are transported into the crossing point in a combination magnet center separately under the fixed main magnetic field. Because of the large energy range of the extracted beam, the stripping probe system is the most critical and complicated device in the dual extraction. In order to save the foil changing time, the structure of the foil changing system in the vacuum is adopted. The foil automatic changing machine is outside the magnetism yoke and 12 pieces foil can be changed in one time. The design and fabrication of the probe system has been finished and it is going to the progress of installation and adjusting. The experimental verification on probe rod driving and foil changing system has been finished in 2010. The whole stripping extraction system will be installed in 2013.

THPFI019	Main Magnet Installation for CYCIAE-100	3336
	Y.L. Lu, W. Jing, Z.H. Wang, T.J. Zhang CIAE, Beijing, People's Republic of China
	The CYCIAE-100 proton cyclotron being constructed in CIAE is designed to extract the proton beam of 100MeV and 200uA. The main magnet is the importantest part of the cyclotron. The diameter of the CYCIAE-100 main magnet is 6160mm. Its height is 3860mm. Its total weight is about 416 tons, and the largest part is about 170 tons. The beamline of CYCIAE-100 will be connected to the HI-13 tandem accelerator at CIAE. So, the CYCIAE-100 main magnet should be installed accurately. The vertical tolerance of the CYCIAE-100 main magnet is 0.20mm, and the horizontal tolerance is 0.50mm. The CYCIAE-100 main magnet is located in an underground building which level is -4m. There is a horizontal hole on the west wall of the accelerator building. All parts of the main magnet had been transported through this horizontal hole. The CYCIAE-100 main magnet had been installed in November 2012 at CIAE. In fact the error of installation is: the vertical 0.10mm, the horizontal 0.20mm. The installation process will be shown in this paper.

THPFI020	Radiation Shielding Design for Medical Cyclotrons	3339
	F. Wang, T. Cui, X.L. Jia, Z.G. Li, T.J. Zhang, X.Z. Zhang CIAE, Beijing, People's Republic of China
	With the increasing applications of cyclotrons in health care, a number of cyclotrons ranging from several MeVs to hundreds MeVs have used for radio diagnostic and radiation therapy. A 14 MeV PET cyclotron, CYCIAE-14, has been installed in a shielding building for tests at CIAE that can be used for FDG production and boron neutron capture therapy (BNCT). In the mean time, the development of a 235MeV cyclotron, CYCIAE-235, which can be used for proton therapy, is in progress at the same laboratory. In terms of the cyclotron application in factories and hospitals, an appropriate radiation shielding design is of critical importance. In the case of CYCIAE-14 and CYCIAE-235, the neutron source of different cyclotrons has been estimated to define the thickness of the total shielding, and the concrete is selected as the main shielding material. For CYCIAE-14 specifically, local shielding has been implemented. This paper will give an introduction to the radiation shielding design for CYCIAE-14 and CYCIAE-235 respectively. The typical layout for the application of the two machines is presented in this paper which can be applied in factories and hospitals as well.

THPFI022	The M-C Application in Designing Tailored Cryopump Used in Cyciae-100 Cyclotron	3342
	S.P. Zhang, Z.G. Li, G.F. Pan, J.S. Xing, F. Yang, T.J. Zhang CIAE, Beijing, People's Republic of China
	A compact high intensity cyclotron CYCIAE-100 was selected as the driver for the Beijing Radioactive Ion Facility (BRIF). A pressure of 5×10-8 mbar is required to achieve acceptable beam losses in the CYCIAE-100 cyclotron. As the existing ports on the cyclotron valley are insufficient to provide enough pumping speed using commercially available pumps, two tailored cryopanels with a pumping speed of 60000 l/s for each are designed. Based on the Monte-Carlo method, a mathematical model of molecular movement and collision between the panels and their shield was developed. The ratio of molecular reflected to the baffle to molecular passing through the baffle is the sticking probability on the panels. When taking the transmission probability of the chevron baffle, capture coefficient of cryopanel can be calculated. It could provide a reference to design the cryopanel shape and its condensation area.

THPME008	Experimental Study of Magnetic Properties for Magnet Material in CYCIAE-100	3525
	J.Q. Zhong, T. Cui, M. Li, C. Wang, Z.H. Wang, J.J. Yang, T.J. Zhang CIAE, Beijing, People's Republic of China
	The magnetic property of magnet material is one of the key factors that influence the distribution of magnetic field in large scale cyclotrons, especially embody on the vertical focusing of field and the first harmonic field error in cyclotron. According to the requirements of the physical design of CYCIAE-100, we have studied the pivotal factors, which impact on the maximum permeability, coercivity and B-H curve of material of CYCIAE-100 magnet, including the cooling rate during magnetic annealing and residual stress. The study results will be shown in this paper.

Paper

Title

Page

Physical Design Progress of an 800 MeV High Power Proton Driver

342

J.J. Yang, Shizhong. An, M. Li, T.J. Zhang, J.Q. Zhong
CIAE, Beijing, People's Republic of China

We presented the conceptual design of an 800 MeV high power proton ring cyclotron in the paper[1] . A more detailed physical design was carried out since then. The most challenging issues regarding the high power operation, including the space charge effects and beam loss during the extraction, are quantitatively studied by using state-of-the-art high performance computation technique. On that basis the fundamental structure of the cyclotron is adjusted and optimized so as to meet the requirements of MW-class operation. Reference: [1] T. Zhang, J. Yang, M. Li, et. al., Conceptual design of an 800 MeV high power proton driver, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 269(24) (2011) 2964-2967

MOPFI029

The Construction Progress of Beijing Radioactive Ion-beam Facility

345

T.J. Zhang, Shizhong. An, B.Q. Cui, Z.G. Li, Y.L. Lu, C.H. Peng, F. Yang
CIAE, Beijing, People's Republic of China

The Beijing Radioactive Ion-Beam Facility (BRIF) is being constructed at CIAE. The project consists of a 100 MeV high intensity cyclotron CYCIAE-100, an ISOL system with a mass resolution of 20000, and a superconducting booster. The construction of the building was started on April 28, 2011 and the roof was sealed on Jan. 16, 2012. The on-site installation conditions have been ready since Sept. 27, 2012. Up to now, the fabrication of all major components for CYCIAE-100 have been completed, including the main magnet system, the RF system, ion source and injection, main vacuum, etc. The equipment fabrication for the ISOL system has been completed and magnetic mapping and shimming is being performed on the large-scale analysis magnet. The fabrication of the major components for the superconducting booster has been accomplished, and the work on copper-niobium sputtering is under way. At present, the installation and assembly is in full swing and the beam commissioning is to predicted to be finished in mid 2013. Taking advantage of the experiences accumulated on the CRM cyclotron with beam up to 430 uA, it is likely that the first beams of 100 MeV can be achieved by the end of 2013.

TUPWA011

Investigation of Emittance Growth in a Small PET Cyclotron CYCIAE-14

1745

M. Li, Shizhong. An, T.J. Zhang
CIAE, Beijing, People's Republic of China

In order to satisfy the rapidly increased domestic needs for PET in China, a small medical cyclotron named CYCIAE-14 is designed and constructed in CIAE ( China Institute of Atomic Energy ) . As the beam intensity in CYCIAE-14 is high, the beam emittance should be controlled strictly in order to reduce the beam loss in the cyclotron. Precessional mixing and resonance crossing are the two main factors leading to emittance growth in the cyclotron with stripping extraction. In this paper, the physical mechanism of precessional mixing in a stripping extraction cyclotron is investigated. After that, the maximum allowable field errors in CYCIAE-14 are derived using the Hamiltonian formalism and numerical simulation, which provides a reference for the cyclotron design and field shimming.

TUPWA012

The Influence of the Magnetic Field Errors in CYCIAE-100 Cyclotron

1748

H.J. Yao, M. Li, T.J. Zhang, J.Q. Zhong
CIAE, Beijing, People's Republic of China

The main magnet size of CYCIAE-100 is 2.31 m in height and 6.16 m in diameter and the outer radius of the sector is 2.0 m, and the total iron weight is about 415t. The magnetic filed can not be absolutely ideal because of imperfections during manufacturing and installation of this big magnet. Therefore the influence of the magnetic field errors on the beam behavior should be studied to provide the reference for magnet mapping and shimming. Magnetic field errors in a cyclotron will excite coherent oscillations through displacing the center of orbit or distorting the transverse phase space. This effect is especially important in the CYCIAE-100 cyclotron because there are a number of different turns in the extracted beam. The tolerances for the magnetic field errors are given in this paper based on analytic calculations and numerical simulations. The resonances vr=1, 2vr=2 driven by the 1st, 2nd harmonic magnetic field are considered, which will result in the radial emittance growth .Besides that, the resonances cause the vertical emittance growth are considered. The maximum allowable field errors for CYCIAE-100 are presented in this paper.

WEPFI026

Design and Commissioning of the RF System of CYCIAE 14 Cyclotron

2759

Z.G. Yin, B. Ji, Y. Lei, P.Z. Li, G.F. Song, C. Wang, T.J. Zhang, Z.L. Zhao
CIAE, Beijing, People's Republic of China

The RF system of CYCIAE-14 consists of a set of 20kW amplifier, two 1/4λ RF cavities connected in central region, the transmission line and a set of LLRF system. The LLRF system, based on DDS and DSP, has achieved the close-loop adjustment of accelerating voltage and the resonant frequency. The RF system design for CYCIAE-14 was started in 2010, and the fabrication of the major equipments was finished in 2011. The installation and commissioning was completed in early 2012, satisfying the design requirements. This article describes the design of the RF system, and summarizes the difficulties encountered in the process of manufacture, installation and commissioning. Some of the problems caused by the transmission line and the RF leakage are analyzed, followed by the measures taken to solve these problems.

THPFI018

The Design and Construction of Stripping Probe System for CYCIAE-100

3333

Shizhong. An, F.P. Guan, P.Z. Li, L.P. Wen, H.D. Xie, Z.G. Yin, T.J. Zhang
CIAE, Beijing, People's Republic of China

A 100 MeV H⁻ compact cyclotron is being constructed in China Institute of Atomic Energy (CYCIAE-100). 75 MeV - 100 MeV proton beams with 200 μA beam intensity will be extracted in dual opposite directions by charge exchange stripping devices. Two stripping probes with carbon foils are inserted radially in the opposite direction from the main magnet pole and the obtained two proton beams after stripping foil are transported into the crossing point in a combination magnet center separately under the fixed main magnetic field. Because of the large energy range of the extracted beam, the stripping probe system is the most critical and complicated device in the dual extraction. In order to save the foil changing time, the structure of the foil changing system in the vacuum is adopted. The foil automatic changing machine is outside the magnetism yoke and 12 pieces foil can be changed in one time. The design and fabrication of the probe system has been finished and it is going to the progress of installation and adjusting. The experimental verification on probe rod driving and foil changing system has been finished in 2010. The whole stripping extraction system will be installed in 2013.

THPFI019

Main Magnet Installation for CYCIAE-100

3336

Y.L. Lu, W. Jing, Z.H. Wang, T.J. Zhang
CIAE, Beijing, People's Republic of China

The CYCIAE-100 proton cyclotron being constructed in CIAE is designed to extract the proton beam of 100MeV and 200uA. The main magnet is the importantest part of the cyclotron. The diameter of the CYCIAE-100 main magnet is 6160mm. Its height is 3860mm. Its total weight is about 416 tons, and the largest part is about 170 tons. The beamline of CYCIAE-100 will be connected to the HI-13 tandem accelerator at CIAE. So, the CYCIAE-100 main magnet should be installed accurately. The vertical tolerance of the CYCIAE-100 main magnet is 0.20mm, and the horizontal tolerance is 0.50mm. The CYCIAE-100 main magnet is located in an underground building which level is -4m. There is a horizontal hole on the west wall of the accelerator building. All parts of the main magnet had been transported through this horizontal hole. The CYCIAE-100 main magnet had been installed in November 2012 at CIAE. In fact the error of installation is: the vertical 0.10mm, the horizontal 0.20mm. The installation process will be shown in this paper.

THPFI020

Radiation Shielding Design for Medical Cyclotrons

3339

F. Wang, T. Cui, X.L. Jia, Z.G. Li, T.J. Zhang, X.Z. Zhang
CIAE, Beijing, People's Republic of China

With the increasing applications of cyclotrons in health care, a number of cyclotrons ranging from several MeVs to hundreds MeVs have used for radio diagnostic and radiation therapy. A 14 MeV PET cyclotron, CYCIAE-14, has been installed in a shielding building for tests at CIAE that can be used for FDG production and boron neutron capture therapy (BNCT). In the mean time, the development of a 235MeV cyclotron, CYCIAE-235, which can be used for proton therapy, is in progress at the same laboratory. In terms of the cyclotron application in factories and hospitals, an appropriate radiation shielding design is of critical importance. In the case of CYCIAE-14 and CYCIAE-235, the neutron source of different cyclotrons has been estimated to define the thickness of the total shielding, and the concrete is selected as the main shielding material. For CYCIAE-14 specifically, local shielding has been implemented. This paper will give an introduction to the radiation shielding design for CYCIAE-14 and CYCIAE-235 respectively. The typical layout for the application of the two machines is presented in this paper which can be applied in factories and hospitals as well.

THPFI022

The M-C Application in Designing Tailored Cryopump Used in Cyciae-100 Cyclotron

3342

S.P. Zhang, Z.G. Li, G.F. Pan, J.S. Xing, F. Yang, T.J. Zhang
CIAE, Beijing, People's Republic of China

A compact high intensity cyclotron CYCIAE-100 was selected as the driver for the Beijing Radioactive Ion Facility (BRIF). A pressure of 5×10-8 mbar is required to achieve acceptable beam losses in the CYCIAE-100 cyclotron. As the existing ports on the cyclotron valley are insufficient to provide enough pumping speed using commercially available pumps, two tailored cryopanels with a pumping speed of 60000 l/s for each are designed. Based on the Monte-Carlo method, a mathematical model of molecular movement and collision between the panels and their shield was developed. The ratio of molecular reflected to the baffle to molecular passing through the baffle is the sticking probability on the panels. When taking the transmission probability of the chevron baffle, capture coefficient of cryopanel can be calculated. It could provide a reference to design the cryopanel shape and its condensation area.

THPME008

Experimental Study of Magnetic Properties for Magnet Material in CYCIAE-100

3525

J.Q. Zhong, T. Cui, M. Li, C. Wang, Z.H. Wang, J.J. Yang, T.J. Zhang
CIAE, Beijing, People's Republic of China

The magnetic property of magnet material is one of the key factors that influence the distribution of magnetic field in large scale cyclotrons, especially embody on the vertical focusing of field and the first harmonic field error in cyclotron. According to the requirements of the physical design of CYCIAE-100, we have studied the pivotal factors, which impact on the maximum permeability, coercivity and B-H curve of material of CYCIAE-100 magnet, including the cooling rate during magnetic annealing and residual stress. The study results will be shown in this paper.