IPAC2018 - List of Authors (Jia, Q.K.)

Paper	Title	Page
THPMK123	Initial Design on the High Quality Electron Beam for the Hefei Advanced Light Source	4605
	R. Huang, Z.G. He, Q.K. Jia, Y. Lu, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Work is supported by China Postdoctoral Science Foundation (Grant No. 51627901) and Chinese Universities Scientific Fund (Contract WK2310000063) The Hefei Advanced Light Source (HALS) was proposed as a future soft X-ray diffraction-limited storage ring with a Free Electron Laser (FEL) at National Synchrotron Radiation Laboratory (NSRL). We present a design for a high brightness electron source as an injector of a 2.4 GeV linac-based diffraction limited storage ring and a free electron laser. The electron beams with low emittance and high peak current will be generated from a photoinjector and designed to fulfill the requirement of the HALS. To compress the bunch length and enhance the pulse current, velocity bunching scenario by a deceleration injection phase is designed. Owing to a linear compression, the electron beam is expected to be extremely short with a further magnetic compression.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK123
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THPMK124	The Radiation Source for a Pre-Bunched THz Free Electron Laser	4608
	R. Huang, Z.G. He, Q.K. Jia, H.T. Li, W.W. Li, Y. Lu, L. Wang, Z. Zhao USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Work is supported by National Natural Science Foundation of China (Grant No. 51627901) Electron beam, generated in a photoinjector and bunched at terahertz (THz) frequency, will excite the coherent THz radiation when entering an undulator. We present a scheme of the radiation source for the pre-bunched THz free electron laser (FEL). The physical design of electron source is described in detail. The radiation frequency is widely tunable by both the pulse train tuning and the undulator gap tuning. It is simulation proved that the radiation power is greatly enhanced in our scheme.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK124
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THPMK126	Numerical Method for Longitudinal Dynamics of a Terahertz Cherenkov Free Electron Laser Driven by a Mev Picosecond Electron Beam	4614
	W.W. Li, Z.G. He, Q.K. Jia, S.M. Jiang, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China D. He Anhui Electrical Engineering Professional Technique College, Hefei, People's Republic of China
	Funding: Natural Science Foundation of China (11705198, 11775216) China Postdoctoral Science Foundation (2017M622023) Fundamental Research Funds for the Central Universities (WK2310000061) Corrugated or dielectric structures have been widely used for producing electron bunch train or THz radiation source. Recently, a novel scheme of sub-terahertz free electron laser (FEL) from a metallic pipe with corrugated walls driven by a non-ultra-relativistic (<10 MeV) picosecond electron beam was proposed and analyzed using the Vlasov-Maxwell equations. In this paper, we use the dielectric loaded waveguide instead, and a numerical method for the longitudinal beam dynamics and electromagnetics of the FEL interaction is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK126
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THPMK127	Terahertz Smith-Purcell Radiation From the High-Harmonic Component of Modulated Electron Beam From Dielectric Structure	4617
	S.M. Jiang, Z.G. He, Q.K. Jia, W.W. Li, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China D. He Anhui Electrical Engineering Professional Technique College, Hefei, People's Republic of China
	Funding: Supported by National Nature Science Foundation of China(11705198, 11775216) In this paper, a new radiation scheme, which adopts the high order harmonic of modulated electron beam from dielectric loaded waveguide to excite the Smith-Purcell terahertz (THz) radiation, is proposed and in-vestigated by numerical simulations. The results show that the radiation with frequency close to 1.0 THz is generated, while, the fundamental bunching frequency of electron beam is 0.28 THz. Thus, this scheme offer a new method to get the higher frequency THz radiation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK127
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THPMK138	Power Enhancement of Free-Electron Lasers Oscillators With the Natural Gradient of a Planar Undulators	4632
SUSPF012	use link to see paper's listing under its alternate paper code
	Z. Zhao, L.J. Chen, Q.K. Jia, H.T. Li USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Work supported by National Natural Science Foundation of China (No. 21327901, 11205156) Transverse Gradient Undulator (TGU) has been proposed with the initial purpose of mitigating the gain degradation in free electron laser (FEL) oscillators driven by beams with a large energy spread. However, a special-designed TGU with a fixed transverse gradient is required to enhance the gain. In this paper, we investigate using the natural field gradient of a normal planar undulator instead of a TGU to enhance the FEL oscillator (FELO) power. In this method, the beam is first vertically dispersed by a dogleg and then the dispersed beam passes through a normal undulator with a vertical off-axis orbit. Theoretical analysis and numerical simulation based on parameters of FELiChEM are presented. It demonstrates that this scheme can enhance the FEL power with careful optimization of dispersion strength and vertical beam orbit offset, especially when the energy spread is relatively large.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK138
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Paper

Title

Page

Initial Design on the High Quality Electron Beam for the Hefei Advanced Light Source

4605

R. Huang, Z.G. He, Q.K. Jia, Y. Lu, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Work is supported by China Postdoctoral Science Foundation (Grant No. 51627901) and Chinese Universities Scientific Fund (Contract WK2310000063)
The Hefei Advanced Light Source (HALS) was proposed as a future soft X-ray diffraction-limited storage ring with a Free Electron Laser (FEL) at National Synchrotron Radiation Laboratory (NSRL). We present a design for a high brightness electron source as an injector of a 2.4 GeV linac-based diffraction limited storage ring and a free electron laser. The electron beams with low emittance and high peak current will be generated from a photoinjector and designed to fulfill the requirement of the HALS. To compress the bunch length and enhance the pulse current, velocity bunching scenario by a deceleration injection phase is designed. Owing to a linear compression, the electron beam is expected to be extremely short with a further magnetic compression.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK123

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THPMK124

The Radiation Source for a Pre-Bunched THz Free Electron Laser

4608

R. Huang, Z.G. He, Q.K. Jia, H.T. Li, W.W. Li, Y. Lu, L. Wang, Z. Zhao
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Work is supported by National Natural Science Foundation of China (Grant No. 51627901)
Electron beam, generated in a photoinjector and bunched at terahertz (THz) frequency, will excite the coherent THz radiation when entering an undulator. We present a scheme of the radiation source for the pre-bunched THz free electron laser (FEL). The physical design of electron source is described in detail. The radiation frequency is widely tunable by both the pulse train tuning and the undulator gap tuning. It is simulation proved that the radiation power is greatly enhanced in our scheme.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK124

Export •

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

THPMK126

Numerical Method for Longitudinal Dynamics of a Terahertz Cherenkov Free Electron Laser Driven by a Mev Picosecond Electron Beam

4614

W.W. Li, Z.G. He, Q.K. Jia, S.M. Jiang, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China
D. He
Anhui Electrical Engineering Professional Technique College, Hefei, People's Republic of China

Funding: Natural Science Foundation of China (11705198, 11775216) China Postdoctoral Science Foundation (2017M622023) Fundamental Research Funds for the Central Universities (WK2310000061)
Corrugated or dielectric structures have been widely used for producing electron bunch train or THz radiation source. Recently, a novel scheme of sub-terahertz free electron laser (FEL) from a metallic pipe with corrugated walls driven by a non-ultra-relativistic (<10 MeV) picosecond electron beam was proposed and analyzed using the Vlasov-Maxwell equations. In this paper, we use the dielectric loaded waveguide instead, and a numerical method for the longitudinal beam dynamics and electromagnetics of the FEL interaction is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK126

Export •

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

THPMK127

Terahertz Smith-Purcell Radiation From the High-Harmonic Component of Modulated Electron Beam From Dielectric Structure

4617

S.M. Jiang, Z.G. He, Q.K. Jia, W.W. Li, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China
D. He
Anhui Electrical Engineering Professional Technique College, Hefei, People's Republic of China

Funding: Supported by National Nature Science Foundation of China(11705198, 11775216)
In this paper, a new radiation scheme, which adopts the high order harmonic of modulated electron beam from dielectric loaded waveguide to excite the Smith-Purcell terahertz (THz) radiation, is proposed and in-vestigated by numerical simulations. The results show that the radiation with frequency close to 1.0 THz is generated, while, the fundamental bunching frequency of electron beam is 0.28 THz. Thus, this scheme offer a new method to get the higher frequency THz radiation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK127

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THPMK138

Power Enhancement of Free-Electron Lasers Oscillators With the Natural Gradient of a Planar Undulators

4632

SUSPF012

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

Z. Zhao, L.J. Chen, Q.K. Jia, H.T. Li
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Work supported by National Natural Science Foundation of China (No. 21327901, 11205156)
Transverse Gradient Undulator (TGU) has been proposed with the initial purpose of mitigating the gain degradation in free electron laser (FEL) oscillators driven by beams with a large energy spread. However, a special-designed TGU with a fixed transverse gradient is required to enhance the gain. In this paper, we investigate using the natural field gradient of a normal planar undulator instead of a TGU to enhance the FEL oscillator (FELO) power. In this method, the beam is first vertically dispersed by a dogleg and then the dispersed beam passes through a normal undulator with a vertical off-axis orbit. Theoretical analysis and numerical simulation based on parameters of FELiChEM are presented. It demonstrates that this scheme can enhance the FEL power with careful optimization of dispersion strength and vertical beam orbit offset, especially when the energy spread is relatively large.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK138

Export •

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