LINAC2016 - List of Authors (Zhao, H.W.)

Paper	Title	Page
MOPRC029	Experiment of Plasma Discharge on HWR Cavity for In-Situ Surface Cleaning Study	133
SPWR008	use link to see paper's listing under its alternate paper code
	A.D. Wu, Y. He, T.C. Jiang, C.L. Li, Y.M. Li, W.M. Yue, S.H. Zhang, H.W. Zhao IMP/CAS, Lanzhou, People's Republic of China L.M. Chen Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China L. Yang IHEP, Beijing, People's Republic of China
	Hydrocarbons, which migrate from the vacuum bumps system, will absorb on the cavity surface after periods of operation. The contaminants can reduce the surface electron work function to enhance the field emission effect and restrict the cavity accelerating gradient. The room temperature in-situ plasma surface processing to clean the hydrocarbon contaminants can act as a convenient and efficient technology for the accelerator on line performance recovery. For better control of the discharge inside the cavity, the experiment works on a single HWR cavity aims to research the ignition between the swarm parameters (gas flow, pressure, forward power).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPRC029
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MOPLR053	Operating Status of Injector II RFQ for C-ADS Project	254
	L.P. Sun, Y. He, C.X. Li, L. Lu, A. Shi, L.B. Shi, W.B. Wang, X.B. Xu, Z.L. Zhang, H.W. Zhao IMP/CAS, Lanzhou, People's Republic of China
	The Radio Frequency Quadrupole system has been designed and constructed for C-ADS (Chinese Accelerator Driven System) Injector II in Institute of Modern Physics (IMP), Chinese Academy of Sciences, which has been running for more than one year until now. It is a quadrilateral four-vane resonator with two equal couplers operating in CW mode. In the paper, RF system upgrade will be presented in detail，especially the two-port configuration was introduced and the conditioning based on two new sets of solid-state amplifier instead of the original tetrodes power source due to system hardware upgrade are described in the paper. RFQ, solid-state amplifier, two-port configuration, coupler
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPLR053
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TUPLR066	High Current Beam Injector for Cancer Therapy	604
	L. Lu, Y. He, C.X. Li, W. Ma, L.B. Shi, L.P. Sun, X.B. Xu, L. Yang, H.W. Zhao IMP/CAS, Lanzhou, People's Republic of China T.L. He USTC/NSRL, Hefei, Anhui, People's Republic of China
	A hybrid single cavity (HSC) linac, which is formed by combining a radio frequency quadrupole (RFQ) and a drift tube (DT) structure into one interdigital-H (IH) cavity, is fabricated and assembled as a proof of principle injector for cancer therapy synchrotron, based on the culmination of several years of research. The HSC linac adopts a direct plasma injection scheme (DPIS), which can inject a high intensity heavy ion beam produced by a laser ion source (LIS). The input beam current of the HSC is designed to be 20 mA C⁶⁺ ions. According to numerical simulations, the HSC linac can accelerate a 6-mA C⁶⁺ beam, which meets the requirement of the needed particle number for cancer therapy (108~9 ions/pulse). The HSC injector with the DPIS method makes the existing multi-turn injection system and stripping system unnecessary, and can also bring down the size of the beam pipe in existing synchrotron magnets, which could reduce the whole cost of synchrotron. The radio frequency (RF) measurements show excellent RF properties for the resonator, with a measured Q equal to 91% of the simulated value. A C⁶⁺ ion beam extracted from the LIS was used for the HSC commissioning. In beam testing, we found the measured beam parameters agreed with simulations. More details of the measurements and the results of the high power test are reported in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR066
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THPLR061	Research on a Two-beam Type Drift Tube Linac	989
	L. Lu, C.X. Li, W. Ma, L.B. Shi, L.P. Sun, X.B. Xu, H.W. Zhao IMP/CAS, Lanzhou, People's Republic of China T.L. He USTC/NSRL, Hefei, Anhui, People's Republic of China L. Yang USTC, Hefei, Anhui, People's Republic of China
	The very high intense heavy-ion beam is a high attraction for heavy ion researches and heavy-ion applications, but it is limited by heavy-ion production of ion source and space-charge-effect in acceleration. There is one way, accelerating several heavy-ion beams in one cavity at same time and funneling them, which could achieve the acceleration of very high intense heavy-ion beam with existing ion source and accelerating technology. In this paper, we will introduce our designs, calculations and simulations of a 2-beam type drift tube linac.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR061
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THPLR064	Design and Simulation of a High Intensity Heavy Ion RFQ Accelerator Injector	999
SPWR019	use link to see paper's listing under its alternate paper code
	W. Ma, Y. He, C.X. Li, L. Lu, L.B. Shi, L.P. Sun, X.B. Xu, Z.L. Zhang, H.W. Zhao IMP/CAS, Lanzhou, People's Republic of China
	An 81.25 MHz continuous wave (CW) radio frequency quadrupole (RFQ) accelerator has been developed for Low Energy Accelerator Facility (LEAF) at the Institute of Modern Physics (IMP), the Chinese Academy of Science (CAS). In the CW operating mode, the proposed RFQ design adopted the conventional four-vane structure. The main design goals are providing the high shunt impendence with low power losses. In the electromagnetic (EM) design, the π-mode stabilizing loops (PISLs) were optimized to produce a good mode separation. The tuners were also designed and optimized to tune frequency and field flatness of the operating mode. The vane undercuts were optimized to provide a flat field along the RFQ cavity. Additionally, a full length model with modulations was set up for the final EM simulations. In this paper, detailed EM design of the LEAF-RFQ will be presented and discussed. Meanwhile, structure error analysis is also studied.
	Poster THPLR064 [3.021 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR064
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FR1A03	Intense Beam Production of Highly Charged Ions by the Superconducting ECR Ion Source SECRAL for Heavy Ion Linacs	1027
	L.T. Sun, X. Fang, Y.C. Feng, J.W. Guo, W. Lu, L.Z. Ma, C. Qian, Z. Shen, W. Wu, Y. Yang, W.H. Zhang, X.Z. Zhang, H.W. Zhao, L. Zhu IMP/CAS, Lanzhou, People's Republic of China
	Superconducting ECR ion source (SC-ECRIS) represents the state of the art technologies of ECR ion sources. Existing SC-ECRISs developed in different labs have contributed significantly for ECRIS technology advancement in the last 15 years. Recently the superconducting ECR ion source SECRAL operated at 24 GHz at IMP has produced many new world recorded beam intensities of highly charged ions due to new technologies applied, such as a new microwave coupling scheme. At the meantime, the world first 4th generation ECR ion source operated at 45 GHz is being developed at IMP. All these developments on intense beam production of highly charged ions with superconducting ECR ion source may play significant roles for the next generation heavy ion linacs such as FRIB and Linac of HIAF project. This paper will report the recent developments of intense highly charged heavy ion beams at IMP and the discussion on perspectives of next generation ECRIS for the future heavy ion liancs.
	Slides FR1A03 [13.557 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-FR1A03
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Paper

Title

Page

MOPRC029

Experiment of Plasma Discharge on HWR Cavity for In-Situ Surface Cleaning Study

133

SPWR008

use link to see paper's listing under its alternate paper code

A.D. Wu, Y. He, T.C. Jiang, C.L. Li, Y.M. Li, W.M. Yue, S.H. Zhang, H.W. Zhao
IMP/CAS, Lanzhou, People's Republic of China
L.M. Chen
Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China
L. Yang
IHEP, Beijing, People's Republic of China

Hydrocarbons, which migrate from the vacuum bumps system, will absorb on the cavity surface after periods of operation. The contaminants can reduce the surface electron work function to enhance the field emission effect and restrict the cavity accelerating gradient. The room temperature in-situ plasma surface processing to clean the hydrocarbon contaminants can act as a convenient and efficient technology for the accelerator on line performance recovery. For better control of the discharge inside the cavity, the experiment works on a single HWR cavity aims to research the ignition between the swarm parameters (gas flow, pressure, forward power).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPRC029

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPLR053

Operating Status of Injector II RFQ for C-ADS Project

254

L.P. Sun, Y. He, C.X. Li, L. Lu, A. Shi, L.B. Shi, W.B. Wang, X.B. Xu, Z.L. Zhang, H.W. Zhao
IMP/CAS, Lanzhou, People's Republic of China

The Radio Frequency Quadrupole system has been designed and constructed for C-ADS (Chinese Accelerator Driven System) Injector II in Institute of Modern Physics (IMP), Chinese Academy of Sciences, which has been running for more than one year until now. It is a quadrilateral four-vane resonator with two equal couplers operating in CW mode. In the paper, RF system upgrade will be presented in detail，especially the two-port configuration was introduced and the conditioning based on two new sets of solid-state amplifier instead of the original tetrodes power source due to system hardware upgrade are described in the paper.
RFQ, solid-state amplifier, two-port configuration, coupler

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPLR053

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPLR066

High Current Beam Injector for Cancer Therapy

604

L. Lu, Y. He, C.X. Li, W. Ma, L.B. Shi, L.P. Sun, X.B. Xu, L. Yang, H.W. Zhao
IMP/CAS, Lanzhou, People's Republic of China
T.L. He
USTC/NSRL, Hefei, Anhui, People's Republic of China

A hybrid single cavity (HSC) linac, which is formed by combining a radio frequency quadrupole (RFQ) and a drift tube (DT) structure into one interdigital-H (IH) cavity, is fabricated and assembled as a proof of principle injector for cancer therapy synchrotron, based on the culmination of several years of research. The HSC linac adopts a direct plasma injection scheme (DPIS), which can inject a high intensity heavy ion beam produced by a laser ion source (LIS). The input beam current of the HSC is designed to be 20 mA C⁶⁺ ions. According to numerical simulations, the HSC linac can accelerate a 6-mA C⁶⁺ beam, which meets the requirement of the needed particle number for cancer therapy (108~9 ions/pulse). The HSC injector with the DPIS method makes the existing multi-turn injection system and stripping system unnecessary, and can also bring down the size of the beam pipe in existing synchrotron magnets, which could reduce the whole cost of synchrotron. The radio frequency (RF) measurements show excellent RF properties for the resonator, with a measured Q equal to 91% of the simulated value. A C⁶⁺ ion beam extracted from the LIS was used for the HSC commissioning. In beam testing, we found the measured beam parameters agreed with simulations. More details of the measurements and the results of the high power test are reported in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR066

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPLR061

Research on a Two-beam Type Drift Tube Linac

989

L. Lu, C.X. Li, W. Ma, L.B. Shi, L.P. Sun, X.B. Xu, H.W. Zhao
IMP/CAS, Lanzhou, People's Republic of China
T.L. He
USTC/NSRL, Hefei, Anhui, People's Republic of China
L. Yang
USTC, Hefei, Anhui, People's Republic of China

The very high intense heavy-ion beam is a high attraction for heavy ion researches and heavy-ion applications, but it is limited by heavy-ion production of ion source and space-charge-effect in acceleration. There is one way, accelerating several heavy-ion beams in one cavity at same time and funneling them, which could achieve the acceleration of very high intense heavy-ion beam with existing ion source and accelerating technology. In this paper, we will introduce our designs, calculations and simulations of a 2-beam type drift tube linac.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR061

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPLR064

Design and Simulation of a High Intensity Heavy Ion RFQ Accelerator Injector

999

SPWR019

use link to see paper's listing under its alternate paper code

W. Ma, Y. He, C.X. Li, L. Lu, L.B. Shi, L.P. Sun, X.B. Xu, Z.L. Zhang, H.W. Zhao
IMP/CAS, Lanzhou, People's Republic of China

An 81.25 MHz continuous wave (CW) radio frequency quadrupole (RFQ) accelerator has been developed for Low Energy Accelerator Facility (LEAF) at the Institute of Modern Physics (IMP), the Chinese Academy of Science (CAS). In the CW operating mode, the proposed RFQ design adopted the conventional four-vane structure. The main design goals are providing the high shunt impendence with low power losses. In the electromagnetic (EM) design, the π-mode stabilizing loops (PISLs) were optimized to produce a good mode separation. The tuners were also designed and optimized to tune frequency and field flatness of the operating mode. The vane undercuts were optimized to provide a flat field along the RFQ cavity. Additionally, a full length model with modulations was set up for the final EM simulations. In this paper, detailed EM design of the LEAF-RFQ will be presented and discussed. Meanwhile, structure error analysis is also studied.

Poster THPLR064 [3.021 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR064

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FR1A03

Intense Beam Production of Highly Charged Ions by the Superconducting ECR Ion Source SECRAL for Heavy Ion Linacs

1027

L.T. Sun, X. Fang, Y.C. Feng, J.W. Guo, W. Lu, L.Z. Ma, C. Qian, Z. Shen, W. Wu, Y. Yang, W.H. Zhang, X.Z. Zhang, H.W. Zhao, L. Zhu
IMP/CAS, Lanzhou, People's Republic of China

Superconducting ECR ion source (SC-ECRIS) represents the state of the art technologies of ECR ion sources. Existing SC-ECRISs developed in different labs have contributed significantly for ECRIS technology advancement in the last 15 years. Recently the superconducting ECR ion source SECRAL operated at 24 GHz at IMP has produced many new world recorded beam intensities of highly charged ions due to new technologies applied, such as a new microwave coupling scheme. At the meantime, the world first 4th generation ECR ion source operated at 45 GHz is being developed at IMP. All these developments on intense beam production of highly charged ions with superconducting ECR ion source may play significant roles for the next generation heavy ion linacs such as FRIB and Linac of HIAF project. This paper will report the recent developments of intense highly charged heavy ion beams at IMP and the discussion on perspectives of next generation ECRIS for the future heavy ion liancs.

Slides FR1A03 [13.557 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-FR1A03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)