IPAC2013 - List of Authors (Yan, X.Q.)

Paper	Title	Page
MOPEA039	Beam Commissioning and Neutron Radiography on a High Current Deuteron RFQ	163
	Y.R. Lu, J. Chen, J.E. Chen, S.L. Gao, Z.Y. Guo, F.J. Jia, G. Liu, S.X. Peng, H.T. Ren, W.L. Xia, X.Q. Yan, K. Zhu PKU, Beijing, People's Republic of China S.Q. Liu, S. Wang, J. Zhao, B.Y. Zou State Key Laboratory of Nuclear Physics and Technology, Beijing, Haidian District, People's Republic of China
	Funding: Supported by NSFC 11079001 and Peking University The high current deuteron RFQ has been developed and widely used in many projects, especially for accelerator based neutron source and its application. This paper reviews not only the recent developments in the world wide, also presents the beam dynamics, structure design ,RF full power test, beam commissioning of PKUNIFTY, which is consisted of a high current very compact ECR source, a 201.5MHz four-rod deuteron RFQ, thicker beryllium target and its moderating, collimation and neutron radiography system. RF and beam commissioning with duty cycle of 4% show the RFQ inter-vane voltage reaches 70kV at about 240kW, the delivered deuteron peak beam current is about 12mA at 290kW with the beam transmission of about 60%. The improvement of transmission is going on. The initial neutron radiography commissioning has been carried out. The results will promote the future development of small accelerator based neutron source.

TUPEA018	Recent Progress of Laser Plasma Proton Accelerator at Peking University	1199
	X.Q. Yan, J.E. Chen, H.Z. Fu, Y.X. Geng, Z.Y. Guo, C. Lin, Y.R. Lu, Y. Shang, Z.X. Yuan, S. Zhao, K. Zhu PKU, Beijing, People's Republic of China
	Funding: National Natural Science Foundation of China (Grant Nos.10935002, 10835003, 11025523) Recent a project called Laser plasma Proton Accelerator (LAPA) is approved by MOST in China. A prototype of laser driven proton accelerator (1~15MeV) based on the PSA mechanism and plasma lens is going to be built at Peking University in the next five years. It can be used for the applications such as cancer therapy, plasma imaging and fast ignition for inertial confine fusion. The recent progress of LAPA is reported here.

TUPEA019	Proton Acceleration driven by High Energy Density Electrons	1202
	S. Zhao, C. Chao, J.E. Chen, H.Z. Fu, Y.X. Geng, C. Lin, B. Liu, H. Wang, X.Q. Yan PKU, Beijing, People's Republic of China
	Resonance Electrons Driving Ion Acceleration S. Zhao, C. Lin, X. Q. Yan Institute of Heavy Ion Physics, Peking University Proton acceleration driven by resonance electrons is proposed. Energetic electron beam generated through direct laser acceleration in the near critical dense plasma is dense and directional. When interacting with a thin foil target, resonance electrons can transmit the target and drive periodical electrostatic field at the back surface, therefore protons are more efficiently accelerated in a much longer distance in propagation direction of resonance electrons, compared to the classical target normal sheath acceleration. For a Gaussian laser pulse with pulse duration of 80fs, peak intensity I=1.38*10⁸W/cm² , the cutoff energy of the output collimated proton beam is 14MeV, enhanced by a factor of 3 or 4. The scaling law predicts hundreds MeV Proton beam can be generated in laser intensity of 10²⁰W/cm².

TUPWA022	Beam Dynamics Design of a 325 MHz RFQ	1772
	F.J. Jia, J.E. Chen, G. Liu, Y.R. Lu, X.Q. Yan PKU, Beijing, People's Republic of China B.Q. Cui, J.H. Li, G.H. Wei CIAE, Beijing, People's Republic of China
	The beam dynamic design of a 325 MHz Radio Frequency Quadrupole (RFQ) is presented in this paper. This 4-vane RFQ will accelerate pulsed proton beam from 30 keV to 3 MeV with repetition frequency of 1 MHz. A 1 MHz chopper and a 5 MHz buncher are arranged in the Low-Energy-Beam-Transport (LEBT) to produce the injected beam. The beam length at the RFQ entrance is about 3 ns, and the energy-spread is about 10%. The code of PARMTEQM is used to simulate RFQ structure. The design should realize high transmission for very high intensity beam meanwhile low emittance growth and relatively short length should be kept.

TUPWA023	Design of the Tuning System for the He⁺ Coupled RFQ-SFRFQ Cavity	1775
	W.L. Xia, J.E. Chen, S.L. Gao, Z.Y. Guo, Y.R. Lu, S.X. Peng, Z. Wang, X.Q. Yan, J. Zhao, K. Zhu PKU, Beijing, People's Republic of China
	Funding: Supported by NSFC 10905003, 11079001, 91026012 Corresponding author: wangzhi@pku.edu.cn The CRS (coupled RFQ-SFRFQ) cavity is a new type linac that couples traditional RFQ (radio frequency quadrupole) and SFRFQ (separated function RFQ) electrodes into a single cavity. The overall design of the CRS cavity has been completed and the linac is being manufactured currently. In this paper, we aimed to design a frequency tuning system for the CRS cavity, which will be used to explore the electromagnetic field distribution between RFQ and SFRFQ sections in the cavity. The frequency range, variation of Q value, power consumption and electric field distribution were investigated. Based on the beam dynamic program SFRFQDYNv1.0, we analysed the beam transmission properties of the cavity under the unbalanced electric field distribution. The optimized parameters of the tuning system were obtained.

THPWO047	The LLRF Measurement and Analysis of the SSC-LINAC RFQ	3875
	G. Liu, J.E. Chen, S.L. Gao, Y.R. Lu, Z. Wang, X.Q. Yan, K. Zhu PKU, Beijing, People's Republic of China X. Du, Y. He, G. Pan, Y.Q. Yang, X. Yin, Y.J. Yuan, Z.L. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: Supported by NSFC(11079001) The manufacturing process of the SSC-LINAC RFQ went to end and the LLRF measurement has been done. The frequency of the RFQ is 53.557 MHz without tuning, which is not far from the design value 53.667 MHz. The unflatness of the field along the beam axis is less than ±4%, which meets the simulation results. The dipole field is in the acceptable margin as well. The frequency will be adjusted by tuning plungers in operation. In this paper, the field distribution along the cavity has been measured and compared with the modulated electrodes simulation. The difference and its influences on the beam transmission have been analyzed.

THPWO048	A CW High Charge State Heavy Ion RFQ for SSC-LINAC	3878
	Y.R. Lu, J.E. Chen, S.L. Gao, G. Liu, Z. Wang, X.Q. Yan, K. Zhu PKU, Beijing, People's Republic of China Y. He, L.P. Sun, J.W. Xia, Y.Q. Yang, X. Yin, Y.J. Yuan, Z.L. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: Supported by NSFC 11079001 To improve the super heavy ion beam injection efficiency and supply high current heavy ion beam for Separated Sector Cyclotron, A CW RFQ for heavy ion with high charge state has been designed and manufactured in the last two years. This RFQ will operate at 53.667MHz, will accelerate super heavy ions such as 238U³⁴⁺ to 143keV/u. This paper will introduce the SSC-LINAC components, especially the RFQ beam dynamics, full length structure design, tuning and cooling method. Furthermore RF system and RF commissioning with full power for the RFQ power cavity will also be presented.

Paper

Title

Page

Beam Commissioning and Neutron Radiography on a High Current Deuteron RFQ

163

Y.R. Lu, J. Chen, J.E. Chen, S.L. Gao, Z.Y. Guo, F.J. Jia, G. Liu, S.X. Peng, H.T. Ren, W.L. Xia, X.Q. Yan, K. Zhu
PKU, Beijing, People's Republic of China
S.Q. Liu, S. Wang, J. Zhao, B.Y. Zou
State Key Laboratory of Nuclear Physics and Technology, Beijing, Haidian District, People's Republic of China

Funding: Supported by NSFC 11079001 and Peking University
The high current deuteron RFQ has been developed and widely used in many projects, especially for accelerator based neutron source and its application. This paper reviews not only the recent developments in the world wide, also presents the beam dynamics, structure design ,RF full power test, beam commissioning of PKUNIFTY, which is consisted of a high current very compact ECR source, a 201.5MHz four-rod deuteron RFQ, thicker beryllium target and its moderating, collimation and neutron radiography system. RF and beam commissioning with duty cycle of 4% show the RFQ inter-vane voltage reaches 70kV at about 240kW, the delivered deuteron peak beam current is about 12mA at 290kW with the beam transmission of about 60%. The improvement of transmission is going on. The initial neutron radiography commissioning has been carried out. The results will promote the future development of small accelerator based neutron source.

TUPEA018

Recent Progress of Laser Plasma Proton Accelerator at Peking University

1199

X.Q. Yan, J.E. Chen, H.Z. Fu, Y.X. Geng, Z.Y. Guo, C. Lin, Y.R. Lu, Y. Shang, Z.X. Yuan, S. Zhao, K. Zhu
PKU, Beijing, People's Republic of China

Funding: National Natural Science Foundation of China (Grant Nos.10935002, 10835003, 11025523)
Recent a project called Laser plasma Proton Accelerator (LAPA) is approved by MOST in China. A prototype of laser driven proton accelerator (1~15MeV) based on the PSA mechanism and plasma lens is going to be built at Peking University in the next five years. It can be used for the applications such as cancer therapy, plasma imaging and fast ignition for inertial confine fusion. The recent progress of LAPA is reported here.

TUPEA019

Proton Acceleration driven by High Energy Density Electrons

1202

S. Zhao, C. Chao, J.E. Chen, H.Z. Fu, Y.X. Geng, C. Lin, B. Liu, H. Wang, X.Q. Yan
PKU, Beijing, People's Republic of China

Resonance Electrons Driving Ion Acceleration S. Zhao, C. Lin, X. Q. Yan Institute of Heavy Ion Physics, Peking University Proton acceleration driven by resonance electrons is proposed. Energetic electron beam generated through direct laser acceleration in the near critical dense plasma is dense and directional. When interacting with a thin foil target, resonance electrons can transmit the target and drive periodical electrostatic field at the back surface, therefore protons are more efficiently accelerated in a much longer distance in propagation direction of resonance electrons, compared to the classical target normal sheath acceleration. For a Gaussian laser pulse with pulse duration of 80fs, peak intensity I=1.38*10⁸W/cm² , the cutoff energy of the output collimated proton beam is 14MeV, enhanced by a factor of 3 or 4. The scaling law predicts hundreds MeV Proton beam can be generated in laser intensity of 10²⁰W/cm².

TUPWA022

Beam Dynamics Design of a 325 MHz RFQ

1772

F.J. Jia, J.E. Chen, G. Liu, Y.R. Lu, X.Q. Yan
PKU, Beijing, People's Republic of China
B.Q. Cui, J.H. Li, G.H. Wei
CIAE, Beijing, People's Republic of China

The beam dynamic design of a 325 MHz Radio Frequency Quadrupole (RFQ) is presented in this paper. This 4-vane RFQ will accelerate pulsed proton beam from 30 keV to 3 MeV with repetition frequency of 1 MHz. A 1 MHz chopper and a 5 MHz buncher are arranged in the Low-Energy-Beam-Transport (LEBT) to produce the injected beam. The beam length at the RFQ entrance is about 3 ns, and the energy-spread is about 10%. The code of PARMTEQM is used to simulate RFQ structure. The design should realize high transmission for very high intensity beam meanwhile low emittance growth and relatively short length should be kept.

TUPWA023

Design of the Tuning System for the He⁺ Coupled RFQ-SFRFQ Cavity

1775

W.L. Xia, J.E. Chen, S.L. Gao, Z.Y. Guo, Y.R. Lu, S.X. Peng, Z. Wang, X.Q. Yan, J. Zhao, K. Zhu
PKU, Beijing, People's Republic of China

Funding: Supported by NSFC 10905003, 11079001, 91026012 Corresponding author: wangzhi@pku.edu.cn
The CRS (coupled RFQ-SFRFQ) cavity is a new type linac that couples traditional RFQ (radio frequency quadrupole) and SFRFQ (separated function RFQ) electrodes into a single cavity. The overall design of the CRS cavity has been completed and the linac is being manufactured currently. In this paper, we aimed to design a frequency tuning system for the CRS cavity, which will be used to explore the electromagnetic field distribution between RFQ and SFRFQ sections in the cavity. The frequency range, variation of Q value, power consumption and electric field distribution were investigated. Based on the beam dynamic program SFRFQDYNv1.0, we analysed the beam transmission properties of the cavity under the unbalanced electric field distribution. The optimized parameters of the tuning system were obtained.

THPWO047

The LLRF Measurement and Analysis of the SSC-LINAC RFQ

3875

G. Liu, J.E. Chen, S.L. Gao, Y.R. Lu, Z. Wang, X.Q. Yan, K. Zhu
PKU, Beijing, People's Republic of China
X. Du, Y. He, G. Pan, Y.Q. Yang, X. Yin, Y.J. Yuan, Z.L. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: Supported by NSFC(11079001)
The manufacturing process of the SSC-LINAC RFQ went to end and the LLRF measurement has been done. The frequency of the RFQ is 53.557 MHz without tuning, which is not far from the design value 53.667 MHz. The unflatness of the field along the beam axis is less than ±4%, which meets the simulation results. The dipole field is in the acceptable margin as well. The frequency will be adjusted by tuning plungers in operation. In this paper, the field distribution along the cavity has been measured and compared with the modulated electrodes simulation. The difference and its influences on the beam transmission have been analyzed.

THPWO048

A CW High Charge State Heavy Ion RFQ for SSC-LINAC

3878

Y.R. Lu, J.E. Chen, S.L. Gao, G. Liu, Z. Wang, X.Q. Yan, K. Zhu
PKU, Beijing, People's Republic of China
Y. He, L.P. Sun, J.W. Xia, Y.Q. Yang, X. Yin, Y.J. Yuan, Z.L. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: Supported by NSFC 11079001
To improve the super heavy ion beam injection efficiency and supply high current heavy ion beam for Separated Sector Cyclotron, A CW RFQ for heavy ion with high charge state has been designed and manufactured in the last two years. This RFQ will operate at 53.667MHz, will accelerate super heavy ions such as 238U³⁴⁺ to 143keV/u. This paper will introduce the SSC-LINAC components, especially the RFQ beam dynamics, full length structure design, tuning and cooling method. Furthermore RF system and RF commissioning with full power for the RFQ power cavity will also be presented.