IPAC2017 - List of Authors (Liu, H.C.)

Paper	Title	Page
TUPVA100	High Power Conditioning and First Beam Acceleration of the CSNS DTL-1	2320
	Y. Wang, A.H. Li, B. Li, J. Peng, P.H. Qu, X.L. Wu CSNS, Guangdong Province, People's Republic of China Q. Chen, M.X. Fan, K.Y. Gong, H.C. Liu IHEP, Beijing, People's Republic of China
	The CSNS DTLs are divided into 4 cavities. The DTL-1 was transferred and installed in the CSNS Linac tunnel in August of 2015. The RF high power conditioning of DTL-1 started in December 2015 and ended in February 2016. At the end, we finished DTL-1 high power conditioning mission with peak power 1.5MW (1.1 times design value), 1.625% duty factor (650us, 25Hz). And the first beam has been successfully accelerated to the design value 21.6MeV with nearly 100% transmission efficiency. In this paper, the details of conditioning process were presented and one severe RF discharge breakdown was described specifically, which occurred during high power conditioning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA100
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THPIK049	High Power Conditioning of the DTL-1 for CSNS	4207
	H.C. Liu, Q. Chen, K.Y. Gong IHEP, Beijing, People's Republic of China M.X. Fan, A.H. Li, B. Li, J. Peng, P.H. Qu, Y. Wang, X.L. Wu CSNS, Guangdong Province, People's Republic of China
	The RF tuning of the first DTL tank for the China spalla-tion neutron source was finished leading to a stabilized-uniform accelerating field. After the installation of the DTL-1 in the linac tunnel, the high power conditioning was carried out deliberately. Consequently a peak RF power of 1.6MW with 25Hz repetition rate and 650'sec pulse width was put into the tank stably. A 3MeV H⁻ ion was injected into the DTL-1 and was successfully accel-erated to 21.6MeV with almost 100% transmission. Dur-ing the operation, The DTL-1 tank worked stable in the design power level. The conditioning details will be pre-sented in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK049
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THPIK050	Measurement and Tuning of the RF Field for the CSNS DTL	4210
	A.H. Li, M.X. Fan, B. Li, J. Peng, P.H. Qu, Y. Wang, X.L. Wu CSNS, Guangdong Province, People's Republic of China Q. Chen, S. Fu, K.Y. Gong, H.C. Liu IHEP, Beijing, People's Republic of China
	The CSNS DTL accelerates negative hydrogen ions from 3MeV to 80MeV with resonant frequency of 324MHz and peak current of 15mA. The CSNS includes four DTL cavities with diameter of 56.6cm and each length of 9 meters. RF properties research and measurement have been done to make sure the design and manufacture validate for beam operation. A new automatic system has been developed for measuring field distribution. The secondary derivation method is used to calculate the amount of the tuners to tune axial field flatness. The tilt of TS curve is used to judge the gap between the post couplers and drift tubes to achieve stability. At last the tanks have good flatness and strong stabilization, the field deviation is 2% with the standard deviation of 0.96%, and the maximum TS parameter is 65%/MHz. After the low power RF tuning experiment, the four tans have been installed in the tunnel, and have gotten good results of high power test and beam acceleration experiment.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK050
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THPIK061	3D Model Analysis of Cavity for CSNS DTL	4236
	P.H. Qu, M.X. Fan, B. Li, Y. Wang CSNS, Guangdong Province, People's Republic of China Q. Chen, K.Y. Gong, A.H. Li, H.C. Liu, F.X. Zhao IHEP, Beijing, People's Republic of China
	An Alvarez-type Drift tube linac (DTL) was utilized to accelerate an H⁻ ion beam from 3 MeV to 80 MeV of China Spallation neutron source (CSNS). RF field profile is always deviate from the design curve due to errors in fabrication and assembly of the structure cells, thus RF tuning of DTL is necessary. CSNS DTL operates in zero mode and has long tank, so accelerating field of which is unstable, this problem was solved through adding post couplers at the both side of cavity wall. In order to speed up the schedule of DTL low power RF tuning, we analyzed the operating mode, field flatness with slug tuners, field stabilization with post couplers by CST Micro wave studio (MWS) mainly with eigenmode solver in advance. Considering saving the computer memory and increasing the calculation speed, we divided each tank model into three short units. Slug tuner depth and PC-DT gap of DTL-1 and DTL-3 by simulation were shown which improved the efficiency of CSNS DTL RF tuning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK061
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Paper

Title

Page

High Power Conditioning and First Beam Acceleration of the CSNS DTL-1

2320

Y. Wang, A.H. Li, B. Li, J. Peng, P.H. Qu, X.L. Wu
CSNS, Guangdong Province, People's Republic of China
Q. Chen, M.X. Fan, K.Y. Gong, H.C. Liu
IHEP, Beijing, People's Republic of China

The CSNS DTLs are divided into 4 cavities. The DTL-1 was transferred and installed in the CSNS Linac tunnel in August of 2015. The RF high power conditioning of DTL-1 started in December 2015 and ended in February 2016. At the end, we finished DTL-1 high power conditioning mission with peak power 1.5MW (1.1 times design value), 1.625% duty factor (650us, 25Hz). And the first beam has been successfully accelerated to the design value 21.6MeV with nearly 100% transmission efficiency. In this paper, the details of conditioning process were presented and one severe RF discharge breakdown was described specifically, which occurred during high power conditioning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA100

Export •

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

THPIK049

High Power Conditioning of the DTL-1 for CSNS

4207

H.C. Liu, Q. Chen, K.Y. Gong
IHEP, Beijing, People's Republic of China
M.X. Fan, A.H. Li, B. Li, J. Peng, P.H. Qu, Y. Wang, X.L. Wu
CSNS, Guangdong Province, People's Republic of China

The RF tuning of the first DTL tank for the China spalla-tion neutron source was finished leading to a stabilized-uniform accelerating field. After the installation of the DTL-1 in the linac tunnel, the high power conditioning was carried out deliberately. Consequently a peak RF power of 1.6MW with 25Hz repetition rate and 650'sec pulse width was put into the tank stably. A 3MeV H⁻ ion was injected into the DTL-1 and was successfully accel-erated to 21.6MeV with almost 100% transmission. Dur-ing the operation, The DTL-1 tank worked stable in the design power level. The conditioning details will be pre-sented in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK049

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

THPIK050

Measurement and Tuning of the RF Field for the CSNS DTL

4210

A.H. Li, M.X. Fan, B. Li, J. Peng, P.H. Qu, Y. Wang, X.L. Wu
CSNS, Guangdong Province, People's Republic of China
Q. Chen, S. Fu, K.Y. Gong, H.C. Liu
IHEP, Beijing, People's Republic of China

The CSNS DTL accelerates negative hydrogen ions from 3MeV to 80MeV with resonant frequency of 324MHz and peak current of 15mA. The CSNS includes four DTL cavities with diameter of 56.6cm and each length of 9 meters. RF properties research and measurement have been done to make sure the design and manufacture validate for beam operation. A new automatic system has been developed for measuring field distribution. The secondary derivation method is used to calculate the amount of the tuners to tune axial field flatness. The tilt of TS curve is used to judge the gap between the post couplers and drift tubes to achieve stability. At last the tanks have good flatness and strong stabilization, the field deviation is 2% with the standard deviation of 0.96%, and the maximum TS parameter is 65%/MHz. After the low power RF tuning experiment, the four tans have been installed in the tunnel, and have gotten good results of high power test and beam acceleration experiment.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK050

Export •

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

THPIK061

3D Model Analysis of Cavity for CSNS DTL

4236

P.H. Qu, M.X. Fan, B. Li, Y. Wang
CSNS, Guangdong Province, People's Republic of China
Q. Chen, K.Y. Gong, A.H. Li, H.C. Liu, F.X. Zhao
IHEP, Beijing, People's Republic of China

An Alvarez-type Drift tube linac (DTL) was utilized to accelerate an H⁻ ion beam from 3 MeV to 80 MeV of China Spallation neutron source (CSNS). RF field profile is always deviate from the design curve due to errors in fabrication and assembly of the structure cells, thus RF tuning of DTL is necessary. CSNS DTL operates in zero mode and has long tank, so accelerating field of which is unstable, this problem was solved through adding post couplers at the both side of cavity wall. In order to speed up the schedule of DTL low power RF tuning, we analyzed the operating mode, field flatness with slug tuners, field stabilization with post couplers by CST Micro wave studio (MWS) mainly with eigenmode solver in advance. Considering saving the computer memory and increasing the calculation speed, we divided each tank model into three short units. Slug tuner depth and PC-DT gap of DTL-1 and DTL-3 by simulation were shown which improved the efficiency of CSNS DTL RF tuning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK061

Export •

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