IPAC2011 - List of Authors (Zhao, J.)

Paper	Title	Page
TUPC034	Design Studies on 100 MeV/100 kW Electron Linac for NSC KIPT Neutron Source on the Base of Subcritical Assembly Driven by Linac	1075
	Y.L. Chi, J. Cao, X.W. Dai, C.D. Deng, M. Hou, X.C. Kong, R.L. Liu, W.B. Liu, C. Ma, G. Pei, H. Song, S.H. Wang, G. Xu, J. Zhao, Z.S. Zhou IHEP Beijing, Beijing, People's Republic of China M.I. Ayzatskiy, I.M. Karnaukhov, V.A. Kushnir, V.V. Mytrochenko, A.Y. Zelinsky NSC/KIPT, Kharkov, Ukraine S. Pei IHEP Beijng, Beijing, People's Republic of China
	In NSC KIPT, Kharkov, Ukraine, a neutron source on the base of subcritical assembly driven by 100 MeV/100 kW electron linear accelerator is under design and development. To provide neutron flux value of about 1013 neutron/s the electron linear accelerator with 100 MeV beam and average beam power of 100 kW will be used. Construction and manufacture of the linear accelerator of such high beam intensity with low emittance and beam losses is a challenging task. In the report the project of the electron linear accelerator of the required beam energy and intensity is described. The accelerator structure and main technical solutions are presented. To overcome the BBU effect of this high average beam current, several effective measures are adopt, such as using constant gradient structure to spread the HOMs frequencies different cells, larger inner radius and shorter section length make the higher group velocity and optimize the structure geometry to keep the shunt impedance as good as possible. After the beam bunching system, a chicane is followed to chopper the beam to avoid the beam lost in the higher energy part.

MOPS034	Progress on Space Charge Compensation Study in Low Energy High Intense H⁺ Beam*	676
	P.N. Lu, Z.Y. Guo, S.X. Peng, Z.X. Yuan, J. Zhao PKU/IHIP, Beijing, People's Republic of China H.T. Ren Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China
	This article lays emphasis on the relationship between the Space Charge Compensation (SCC) and the beam quality in different conditions. Ar and Kr are used to compensate a 35keV/90mA H⁺ beam with the gas pressure from 3.7×10^-4 Pa to 6×10^-3 Pa. Experiments are conducted in different compensation states with three approaches. With an energy spectrometer, we have got the energy spectra of Extra Compensation Gas Ions (ECGI). By a beam profile meter, the beam profiles are obtained when the injection of compensation gas is gradually rising. In the meantime, the beam emittance is measured under different compensation conditions. After measurements of the above data, the potential and the rest charge distributions in the beam are calculated by analyzing the ECGI energy spectra and beam profiles. All experiments performed aimed to seek out the best circumstance for SCC dominated low energy high intensity ion beams.together to calculate the potential distribution are calculated by analyzing the energy spectra and beam profiles. All experiments performed aimed to seeking for the best circumstances in SCC dominated low energy high intensity ion beams.

WEPC145	Progress in Developing a PLC Control System for the PKUNIFTY	2331
	J. Zhao, J.E. Chen, Z.Y. Guo, Y.R. Lu, S.X. Peng, Q.F. Zhou PKU/IHIP, Beijing, People's Republic of China
	A compact remote PLC control system has been developed for the PKUNIFTY (Peking University Neutron Imaging FaciliTY). That facility is based on a 2 MeV deuteron RFQ accelerator. The PLC control system has been successfully used for the injector including ECR ion source and LEBT, and it worked reliably last year. Now the control of RFQ cavity, HEBT and Be target has been completed and tested. The interlock system has been enhanced. A low level RF control system, including the auto frequency control (AFC) and auto gain control (AGC) circuits, has been designed for the RFQ’s RF power system. Those circuits will work as a lower controller of the PLC control system. The main running parameters can be controlled by setting any desired range of values on the HMI. Test results of hardware and software are presented.

THPS021	Methods to Obtain High Intensity Proton Ion Beams with Low Emittance from ECR Ion Source at Peking University	3463
	H.T. Ren Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China J.E. Chen, Z.Y. Guo, P.N. Lu, S.X. Peng, Z.Z. Song, J.X. Yu, M. Zhang, J. Zhao, Q.F. Zhou PKU/IHIP, Beijing, People's Republic of China
	Funding: Supported by the National Science Foundation of China 11075008. With the development of accelerator technology, to obtain an ion beam with high intensity and low emittance is becoming one of the main goals of research for ion sources. At Peking University we have developed several 2.45 GHz electron cyclotron resonance (ECR) ion sources for different projects and we paid close attention to the beam intensity increasing as well as the beam emittance reduction. Methods are adopted to improve beam intensity by increasing the density of plasma inside the discharge chamber, optimizing the geometry pinch effect and the perveance at the extraction aperture. To suppress the emmitance increasing of an extracted beam, the shape of the electrodes as well as the voltage of suppression electrode are carefully selected With these efforts, a 120 mA total proton beam has been extracted from the permanent magnet ECR ion source at 50 kV, and the measured normalized rms emittance is less than 0.2 pi.mm.mrad. The beam current density at the extraction aperture is about 420 mA/cm².

Paper

Title

Page

Design Studies on 100 MeV/100 kW Electron Linac for NSC KIPT Neutron Source on the Base of Subcritical Assembly Driven by Linac

1075

Y.L. Chi, J. Cao, X.W. Dai, C.D. Deng, M. Hou, X.C. Kong, R.L. Liu, W.B. Liu, C. Ma, G. Pei, H. Song, S.H. Wang, G. Xu, J. Zhao, Z.S. Zhou
IHEP Beijing, Beijing, People's Republic of China
M.I. Ayzatskiy, I.M. Karnaukhov, V.A. Kushnir, V.V. Mytrochenko, A.Y. Zelinsky
NSC/KIPT, Kharkov, Ukraine
S. Pei
IHEP Beijng, Beijing, People's Republic of China

In NSC KIPT, Kharkov, Ukraine, a neutron source on the base of subcritical assembly driven by 100 MeV/100 kW electron linear accelerator is under design and development. To provide neutron flux value of about 1013 neutron/s the electron linear accelerator with 100 MeV beam and average beam power of 100 kW will be used. Construction and manufacture of the linear accelerator of such high beam intensity with low emittance and beam losses is a challenging task. In the report the project of the electron linear accelerator of the required beam energy and intensity is described. The accelerator structure and main technical solutions are presented. To overcome the BBU effect of this high average beam current, several effective measures are adopt, such as using constant gradient structure to spread the HOMs frequencies different cells, larger inner radius and shorter section length make the higher group velocity and optimize the structure geometry to keep the shunt impedance as good as possible. After the beam bunching system, a chicane is followed to chopper the beam to avoid the beam lost in the higher energy part.

MOPS034

Progress on Space Charge Compensation Study in Low Energy High Intense H⁺ Beam*

676

P.N. Lu, Z.Y. Guo, S.X. Peng, Z.X. Yuan, J. Zhao
PKU/IHIP, Beijing, People's Republic of China
H.T. Ren
Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China

This article lays emphasis on the relationship between the Space Charge Compensation (SCC) and the beam quality in different conditions. Ar and Kr are used to compensate a 35keV/90mA H⁺ beam with the gas pressure from 3.7×10^-4 Pa to 6×10^-3 Pa. Experiments are conducted in different compensation states with three approaches. With an energy spectrometer, we have got the energy spectra of Extra Compensation Gas Ions (ECGI). By a beam profile meter, the beam profiles are obtained when the injection of compensation gas is gradually rising. In the meantime, the beam emittance is measured under different compensation conditions. After measurements of the above data, the potential and the rest charge distributions in the beam are calculated by analyzing the ECGI energy spectra and beam profiles. All experiments performed aimed to seek out the best circumstance for SCC dominated low energy high intensity ion beams.together to calculate the potential distribution are calculated by analyzing the energy spectra and beam profiles. All experiments performed aimed to seeking for the best circumstances in SCC dominated low energy high intensity ion beams.

WEPC145

Progress in Developing a PLC Control System for the PKUNIFTY

2331

J. Zhao, J.E. Chen, Z.Y. Guo, Y.R. Lu, S.X. Peng, Q.F. Zhou
PKU/IHIP, Beijing, People's Republic of China

A compact remote PLC control system has been developed for the PKUNIFTY (Peking University Neutron Imaging FaciliTY). That facility is based on a 2 MeV deuteron RFQ accelerator. The PLC control system has been successfully used for the injector including ECR ion source and LEBT, and it worked reliably last year. Now the control of RFQ cavity, HEBT and Be target has been completed and tested. The interlock system has been enhanced. A low level RF control system, including the auto frequency control (AFC) and auto gain control (AGC) circuits, has been designed for the RFQ’s RF power system. Those circuits will work as a lower controller of the PLC control system. The main running parameters can be controlled by setting any desired range of values on the HMI. Test results of hardware and software are presented.

THPS021

Methods to Obtain High Intensity Proton Ion Beams with Low Emittance from ECR Ion Source at Peking University

3463

H.T. Ren
Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China
J.E. Chen, Z.Y. Guo, P.N. Lu, S.X. Peng, Z.Z. Song, J.X. Yu, M. Zhang, J. Zhao, Q.F. Zhou
PKU/IHIP, Beijing, People's Republic of China

Funding: Supported by the National Science Foundation of China 11075008.
With the development of accelerator technology, to obtain an ion beam with high intensity and low emittance is becoming one of the main goals of research for ion sources. At Peking University we have developed several 2.45 GHz electron cyclotron resonance (ECR) ion sources for different projects and we paid close attention to the beam intensity increasing as well as the beam emittance reduction. Methods are adopted to improve beam intensity by increasing the density of plasma inside the discharge chamber, optimizing the geometry pinch effect and the perveance at the extraction aperture. To suppress the emmitance increasing of an extracted beam, the shape of the electrodes as well as the voltage of suppression electrode are carefully selected With these efforts, a 120 mA total proton beam has been extracted from the permanent magnet ECR ion source at 50 kV, and the measured normalized rms emittance is less than 0.2 pi.mm.mrad. The beam current density at the extraction aperture is about 420 mA/cm².