IPAC2014 - List of Authors (Staples, J.W.)

Paper	Title	Page
MOPRI054	Status of the APEX Project at LBNL	727
	F. Sannibale, K.M. Baptiste, C.W. Cork, J.N. Corlett, S. De Santis, L.R. Doolittle, J.A. Doyle, D. Filippetto, G.L. Harris, G. Huang, H. Huang, R. Huang, T.D. Kramasz, S. Kwiatkowski, R.E. Lellinger, V. Moroz, W.E. Norum, C. F. Papadopoulos, G.J. Portmann, H.J. Qian, J.W. Staples, M. Vinco, S.P. Virostek, R.P. Wells, M.S. Zolotorev LBNL, Berkeley, California, USA R. Huang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231 The Advanced Photo-injector EXperiment (APEX) at the Lawrence Berkeley National Laboratory (LBNL), consists in the development of an injector designed to demonstrate the capability of the VHF gun, a normal conducting 186 MHz RF gun operating in CW mode, to deliver the brightness required by X-ray FEL applications at MHz repetition rate. APEX is organized in 3 main phases where different aspects of the required performance are gradually demonstrated. The status and future plans for the project are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI054
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MOPRI055	APEX Present Experimental Results	730
	D. Filippetto, C.W. Cork, S. De Santis, L.R. Doolittle, G. Huang, R. Huang, W.E. Norum, C. F. Papadopoulos, G.J. Portmann, H.J. Qian, F. Sannibale, J.W. Staples, R.P. Wells LBNL, Berkeley, California, USA J. Yang TUB, Beijing, People's Republic of China
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231 The APEX electron source at LBNL combines high-repetition-rate and high beam brightness typical of photo-guns, delivering low emittance electron pulses at MHz frequency. Proving the high beam quality of the beam is an essential step for the success of the experiment. It would enable high repetition rate operations for brightness-hungry applications such as X-Ray FELs, and MHz ultrafast electron diffraction. A full 6D characterization of the beam phase space at the gun beam energy (750 keV) is foreseen in the first phase of the project. Diagnostics for low and high current measurements have been installed and tested, measuring the performances of different cathode materials in a RF environment with mA average current. A double-slit system allows the characterization of beam emittance at high charge and full current (mA). An rf deflecting cavity and a high precision spectrometer allow the characterization of the longitudinal phase space. Here we present the latest results at low and high repetition rate, discussing the tools and techniques used.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI055
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MOPRI056	Design and Fabrication of a VHF - CW High Repetition Rate Electron Gun	733
	R.P. Wells, B. Ghiorso, F. Sannibale, J.W. Staples LBNL, Berkeley, California, USA T.M. Huang IHEP, Beijing, People's Republic of China
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231 A high repetition rate, MHz, electron source is a key element in future FEL based light sources. The Advance Photo-injector Experiment (APEX) at Lawrence Berkeley National Laboratory (LBNL) consists of a high repetition rate 186 MHz (VHF-band) CW electron gun, 1 MHz UV laser source and the diagnostic components necessary to quantify the gun’s performance. The gun design is based on well established, conventional RF cavity design, with a couple notable exceptions. The basis for the selection of this technology, novel design features, fabrication techniques and measured cavity performance are presented.
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THPME027	Development of the injector II RFQ for China ADS project	3280
	Z.L. Zhang, Y.H. Guo, Y. He, H. Jia, C.X. Li, Y. Liu, L. Lu, G. Pan, A. Shi, L.B. Shi, L.P. Sun, W.B. Wang, X.W. Wang, J.X. Wu, Q. Wu, X.B. Xu, B. Zhang, J.H. Zhang, H.W. Zhao, T.M. Zhu IMP, Lanzhou, People's Republic of China M.D. Hoff, A.R. Lambert, D. Li, J.W. Staples, S.P. Virostek LBNL, Berkeley, California, USA C. Zhang GSI, Darmstadt, Germany
	As one of the main components of the injector II of China ADS LINAC project, an RFQ working at 162.5MHz is used to accelerate proton beams of 15mA from 30 keV to 2.1 MeV. The four vane RFQ has been designed in collaboration with Lawrence Berkeley National Laboratory and built at the workshop of the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS). Low power test of the cavity have been completed, and it shows the field flatness is within ±1% and the unloaded Q is 12600. RF conditioning has been completed, results of preliminary beam test show the output beam energy is 2.16 MeV with energy spread of 3.5% and the transmission efficiency is 97.9%. Continuous wave (CW) beam of 2.3 mA has been accelerated for more than one hour.
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THPRI066	Design of a 1.3 GHz Two-cell Buncher for APEX	3924
	H.J. Qian, K.M. Baptiste, J.A. Doyle, D. Filippetto, S. Kwiatkowski, C. F. Papadopoulos, D. Patino, F. Sannibale, J.W. Staples, S.P. Virostek, R.P. Wells LBNL, Berkeley, California, USA
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231 The design of a 1.3 GHz buncher cavity for the APEX project, a MHz repetition rate high-brightness photoinjector, is presented. The buncher cavity operates at 240 kV in CW mode, and it compresses the 750 keV beam from APEX gun through ballistic compression. Compared with a single cell design, a two-cell cavity doubles the shunt impedance to 7.8 MΩ, which greatly relaxes the requirements for both RF amplifier and cavity cooling. Coupler design, multipacting analysis, HOM analysis and thermal analysis will be presented in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI066
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Paper

Title

Page

Status of the APEX Project at LBNL

727

F. Sannibale, K.M. Baptiste, C.W. Cork, J.N. Corlett, S. De Santis, L.R. Doolittle, J.A. Doyle, D. Filippetto, G.L. Harris, G. Huang, H. Huang, R. Huang, T.D. Kramasz, S. Kwiatkowski, R.E. Lellinger, V. Moroz, W.E. Norum, C. F. Papadopoulos, G.J. Portmann, H.J. Qian, J.W. Staples, M. Vinco, S.P. Virostek, R.P. Wells, M.S. Zolotorev
LBNL, Berkeley, California, USA
R. Huang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231
The Advanced Photo-injector EXperiment (APEX) at the Lawrence Berkeley National Laboratory (LBNL), consists in the development of an injector designed to demonstrate the capability of the VHF gun, a normal conducting 186 MHz RF gun operating in CW mode, to deliver the brightness required by X-ray FEL applications at MHz repetition rate. APEX is organized in 3 main phases where different aspects of the required performance are gradually demonstrated. The status and future plans for the project are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI054

Export •

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

MOPRI055

APEX Present Experimental Results

730

D. Filippetto, C.W. Cork, S. De Santis, L.R. Doolittle, G. Huang, R. Huang, W.E. Norum, C. F. Papadopoulos, G.J. Portmann, H.J. Qian, F. Sannibale, J.W. Staples, R.P. Wells
LBNL, Berkeley, California, USA
J. Yang
TUB, Beijing, People's Republic of China

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231
The APEX electron source at LBNL combines high-repetition-rate and high beam brightness typical of photo-guns, delivering low emittance electron pulses at MHz frequency. Proving the high beam quality of the beam is an essential step for the success of the experiment. It would enable high repetition rate operations for brightness-hungry applications such as X-Ray FELs, and MHz ultrafast electron diffraction. A full 6D characterization of the beam phase space at the gun beam energy (750 keV) is foreseen in the first phase of the project. Diagnostics for low and high current measurements have been installed and tested, measuring the performances of different cathode materials in a RF environment with mA average current. A double-slit system allows the characterization of beam emittance at high charge and full current (mA). An rf deflecting cavity and a high precision spectrometer allow the characterization of the longitudinal phase space. Here we present the latest results at low and high repetition rate, discussing the tools and techniques used.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI055

Export •

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

MOPRI056

Design and Fabrication of a VHF - CW High Repetition Rate Electron Gun

733

R.P. Wells, B. Ghiorso, F. Sannibale, J.W. Staples
LBNL, Berkeley, California, USA
T.M. Huang
IHEP, Beijing, People's Republic of China

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231
A high repetition rate, MHz, electron source is a key element in future FEL based light sources. The Advance Photo-injector Experiment (APEX) at Lawrence Berkeley National Laboratory (LBNL) consists of a high repetition rate 186 MHz (VHF-band) CW electron gun, 1 MHz UV laser source and the diagnostic components necessary to quantify the gun’s performance. The gun design is based on well established, conventional RF cavity design, with a couple notable exceptions. The basis for the selection of this technology, novel design features, fabrication techniques and measured cavity performance are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI056

Export •

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

THPME027

Development of the injector II RFQ for China ADS project

3280

Z.L. Zhang, Y.H. Guo, Y. He, H. Jia, C.X. Li, Y. Liu, L. Lu, G. Pan, A. Shi, L.B. Shi, L.P. Sun, W.B. Wang, X.W. Wang, J.X. Wu, Q. Wu, X.B. Xu, B. Zhang, J.H. Zhang, H.W. Zhao, T.M. Zhu
IMP, Lanzhou, People's Republic of China
M.D. Hoff, A.R. Lambert, D. Li, J.W. Staples, S.P. Virostek
LBNL, Berkeley, California, USA
C. Zhang
GSI, Darmstadt, Germany

As one of the main components of the injector II of China ADS LINAC project, an RFQ working at 162.5MHz is used to accelerate proton beams of 15mA from 30 keV to 2.1 MeV. The four vane RFQ has been designed in collaboration with Lawrence Berkeley National Laboratory and built at the workshop of the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS). Low power test of the cavity have been completed, and it shows the field flatness is within ±1% and the unloaded Q is 12600. RF conditioning has been completed, results of preliminary beam test show the output beam energy is 2.16 MeV with energy spread of 3.5% and the transmission efficiency is 97.9%. Continuous wave (CW) beam of 2.3 mA has been accelerated for more than one hour.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME027

Export •

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

THPRI066

Design of a 1.3 GHz Two-cell Buncher for APEX

3924

H.J. Qian, K.M. Baptiste, J.A. Doyle, D. Filippetto, S. Kwiatkowski, C. F. Papadopoulos, D. Patino, F. Sannibale, J.W. Staples, S.P. Virostek, R.P. Wells
LBNL, Berkeley, California, USA

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231
The design of a 1.3 GHz buncher cavity for the APEX project, a MHz repetition rate high-brightness photoinjector, is presented. The buncher cavity operates at 240 kV in CW mode, and it compresses the 750 keV beam from APEX gun through ballistic compression. Compared with a single cell design, a two-cell cavity doubles the shunt impedance to 7.8 MΩ, which greatly relaxes the requirements for both RF amplifier and cavity cooling. Coupler design, multipacting analysis, HOM analysis and thermal analysis will be presented in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI066

Export •

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