FEL2017 - List of Authors (Gai, W.)

Paper	Title	Page
TUP054	Preparations for Installation of the Double Emittance-Exchange Beamline at the Argonne Wakefield Accelerator Facility	340
	G. Ha PAL, Pohang, Republic of Korea M.E. Conde, D.S. Doran, W. Gai, J.G. Power ANL, Argonne, Illinois, USA
	Funding: This work is supported by Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357. Preparations to upgrade the single EEX beamline at the Argonne Wakefield Accelerator (AWA) facility to a double EEX beamline are underway. The single EEX beamline recently demonstrated exchange-based longitudinal bunch shaping (LBS) which has numerous applications including high-energy physics linear colliders, x-ray FELs, and intense radiation sources. The exchange-based method can generate arbitrary LBS in the ideal case but has limitations in the real case. The double EEX beamline was proposed as a means to overcome the limitations of single EEX due to transverse jitter and large horizontal emittance. In this paper, we present the current status of beamline design and installation and simulation results for the planned experiments: collinear wakefield acceleration with tailored beams and tunable bunch compression without the double-horn feature.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-TUP054
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WEP029	Recent Experimental Results on High-Peak-Current Electron Bunch and Bunch Trains Interacting With a THz Undulator	482
	X.L. Su, Y. C. Du, W. Gai, W.-H. Huang, Y.F. Liang, C.-X. Tang, D. Wang, L.X. Yan TUB, Beijing, People's Republic of China
	Funding: supported by the National Natural Science Foundation of China (NSFC Grants No. 11475097) and National Key Scientific Instrument and Equipment Development Project of China (Grants No. 2013YQ12034504). In this paper, experimental results based on THz undulator with widely tunable gap installed at Tsinghua Thomson scattering X-ray (TTX) beamline are introduced. This is a planar permanent magnetic device with 8 regular periods, each 10 cm long. The undulator parameter varies from 9.24-1.39 by changing the magnetic gap from 23mm to 75mm. The coherent undulator radiation can be used as a narrow-band THz source with central frequency ranging from 0.4 THz to 10 THz. The bunch length was figured out from the radiation intensity at different undulator gap, which agreed well with simulations. Furthermore, slice energy modulation was directly observed when high-peak-current bunch trains based on nonlinear longitudinal space charge oscillation passed through the undulator. The demonstrated experiment in THz regime provides a significant scaled tool for FEL mechanism exploration owing to the simplicity of bunch modulation and diagnostics in this range. * Corresponding author: yanlx@mail.tsinghua.edu.cn
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-WEP029
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Preparations for Installation of the Double Emittance-Exchange Beamline at the Argonne Wakefield Accelerator Facility

340

G. Ha
PAL, Pohang, Republic of Korea
M.E. Conde, D.S. Doran, W. Gai, J.G. Power
ANL, Argonne, Illinois, USA

Funding: This work is supported by Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
Preparations to upgrade the single EEX beamline at the Argonne Wakefield Accelerator (AWA) facility to a double EEX beamline are underway. The single EEX beamline recently demonstrated exchange-based longitudinal bunch shaping (LBS) which has numerous applications including high-energy physics linear colliders, x-ray FELs, and intense radiation sources. The exchange-based method can generate arbitrary LBS in the ideal case but has limitations in the real case. The double EEX beamline was proposed as a means to overcome the limitations of single EEX due to transverse jitter and large horizontal emittance. In this paper, we present the current status of beamline design and installation and simulation results for the planned experiments: collinear wakefield acceleration with tailored beams and tunable bunch compression without the double-horn feature.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-TUP054

Export •

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

WEP029

Recent Experimental Results on High-Peak-Current Electron Bunch and Bunch Trains Interacting With a THz Undulator

482

X.L. Su, Y. C. Du, W. Gai, W.-H. Huang, Y.F. Liang, C.-X. Tang, D. Wang, L.X. Yan
TUB, Beijing, People's Republic of China

Funding: supported by the National Natural Science Foundation of China (NSFC Grants No. 11475097) and National Key Scientific Instrument and Equipment Development Project of China (Grants No. 2013YQ12034504).
In this paper, experimental results based on THz undulator with widely tunable gap installed at Tsinghua Thomson scattering X-ray (TTX) beamline are introduced. This is a planar permanent magnetic device with 8 regular periods, each 10 cm long. The undulator parameter varies from 9.24-1.39 by changing the magnetic gap from 23mm to 75mm. The coherent undulator radiation can be used as a narrow-band THz source with central frequency ranging from 0.4 THz to 10 THz. The bunch length was figured out from the radiation intensity at different undulator gap, which agreed well with simulations. Furthermore, slice energy modulation was directly observed when high-peak-current bunch trains based on nonlinear longitudinal space charge oscillation passed through the undulator. The demonstrated experiment in THz regime provides a significant scaled tool for FEL mechanism exploration owing to the simplicity of bunch modulation and diagnostics in this range.
* Corresponding author: yanlx@mail.tsinghua.edu.cn

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-WEP029

Export •

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