IPAC2021 - List of Authors (Liu, B.)

Paper	Title	Page
TUPAB072	The Status of a Grating Monochromator for Soft X-Ray Self-Seeding Experiment at SHINE	1532
	K.Q. Zhang SSRF, Shanghai, People’s Republic of China H.X. Deng, C. Feng, B. Liu, T. Liu SARI-CAS, Pudong, Shanghai, People’s Republic of China
	The research status of a grating monochromator for soft X-ray self-seeding experiment at SHINE has been presented in this paper. The monochromator system includes the vacuum cavity, optical elements, and mechanical movement devices. Until now, the vacuum cavity has finished the manufactured process completely, the optical mirrors have finished machining and measured by the longitudinal trace profiler (LTP) and atomic force microscope (AFM). To make sure the monochromator system can achieve an optical resolution of 1/10000 at the photon energy of 700-1300eV, the system has been integrated and tested recently. In this year, the previous online experiment will be performed in the shanghai soft X-ray free-electron laser (FEL) user facility.
	Poster TUPAB072 [0.717 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB072
About •	paper received ※ 11 May 2021 paper accepted ※ 09 June 2021 issue date ※ 01 September 2021
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TUPAB073	The Design of EEHG Cascaded Harmonic Lasing for SXFEL User Facility	1536
	K.Q. Zhang, C. Feng SSRF, Shanghai, People’s Republic of China H.X. Deng, B. Liu, T. Liu SARI-CAS, Pudong, Shanghai, People’s Republic of China
	The preliminary design and simulation results of EEHG cascaded harmonic lasing for the SXFEL user facility have been presented in this paper. Using the basic seeded beamline of the SXFEL user facility, the designed parameters are optimized to obtain full coherent FEL output at the 90th harmonic of a 265 nm seed laser. According to the designed parameters and the layout of the SXFEL user facility, the detailed simulations are carried out, the results show that the seeded beamline of the SXFEL user facility can generate 2.93 nm full coherent radiation by the proposed method, which indicates that the method can extend the photon energy range of a seeded FEL and the method can be achieved at the SXFEL user facility.
	Poster TUPAB073 [0.955 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB073
About •	paper received ※ 11 May 2021 paper accepted ※ 10 June 2021 issue date ※ 27 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAB078	Relative Timing Jitter Effects on Two-stage Seeded FEL at SHINE	1551
	H.X. Yang SINAP, Shanghai, People’s Republic of China H.X. Deng, B. Liu, D. Wang, K.S. Zhou SARI-CAS, Pudong, Shanghai, People’s Republic of China
	Funding: The National Key Research and Development Program of China (Grants No. 2016YFA0401901, No. 2018YFE0103100) and the National Natural Science Foundation of China (Grants No. 11935020, No. 11775293). The synchronization between the ultrashort electron beam and external seed laser is essential for seeded FELs, especially for a multi-stage one. In this paper, we demonstrate a simple method to obtain the correlations between the pulse energy and relative timing jitter for evaluating the corresponding effects. In this method, the sensitivity of the output FEL performance against electron beam properties is demonstrated by scanning the electron beam and seed lasers, and the fitted curve is used to predict the pulse energy in different timing jitter by random sampling. The results indicate that the pulse energy of the first-stage EEHG is more stable than the second-stage HGHG. Meanwhile, the rise of bunch charge from 100 pC to 300 pC can reduce the timing control requirement by a factor of least 3 for the RMS timing jitter in our numerical simulations based on the parameters of Shanghai High-Repetition-Rate XFEL and Extreme Light Facility. The timing jitter study can demonstrate the feasibility of the EEHG-HGHG cascading scheme in different current profiles for generating Fourier-transform-limited soft X-ray FEL.
	Poster TUPAB078 [0.866 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB078
About •	paper received ※ 11 May 2021 paper accepted ※ 11 June 2021 issue date ※ 21 August 2021
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TUPAB080	Design and Status of the Beam Switchyard of the Shanghai Soft X-Ray FEL User Facility	1559
	S. Chen, R. Wang SSRF, Shanghai, People’s Republic of China H.X. Deng, C. Feng, X. Fu, B. Liu SARI-CAS, Pudong, Shanghai, People’s Republic of China
	SXFEL-UF, a soft X-ray FEL user facility located in Shanghai, has been upgraded from the existing test facility. Electron energy increases from 840 MeV to 1.5 GeV and a SASE FEL line will be added besides the existing seeding FEL line. It has started commissioning since early this year. In order for simultaneous operation of the two FEL lines, a beam switchyard is built between the linac and the two FEL lines. In this paper, the physics design of the beam switchyard is described.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB080
About •	paper received ※ 19 May 2021 paper accepted ※ 11 June 2021 issue date ※ 20 August 2021
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TUPAB089	Proof-of-Principle Experiment Design for PEHG-FEL in SXFEL User Facility	1589
	Z. Qi, H.X. Deng, C. Feng, B. Liu SARI-CAS, Pudong, Shanghai, People’s Republic of China S. Chen, Z.T. Zhao SSRF, Shanghai, People’s Republic of China
	In this paper, we demonstrate a proof-of-principle experimental design for phase-merging enhanced harmonic generation (PEHG) free electron laser (FEL) in Shanghai Soft X-ray Free Electron Laser (SXFEL) user facility. The simulation results indicate that, taking advantage of the beam switchyard, the normal modulator and the seeded FEL line in SXFEL user facility, together with an oblique incident seed laser, we can perform the phase-merging effect in PEHG and finally get an 8.86nm FEL radiation through the undulator, which is the 30th harmonic of the seed laser.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB089
About •	paper received ※ 19 May 2021 paper accepted ※ 17 June 2021 issue date ※ 02 September 2021
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TUPAB121	Photoinjector Drive Laser Temporal Shaping for Shanghai Soft X-Ray Free Electron Laser	1674
	C.L. Li, X.T. Wang, W.Y. Zhang Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China X.L. Dai SSRF, Shanghai, People’s Republic of China H.X. Deng, L. Feng, B. Liu, J.G. Wang SARI-CAS, Pudong, Shanghai, People’s Republic of China
	Shanghai soft X ray free electron laser (SXFEL) initial designed shape of the photocathode driver laser is flattop produced by α-BBO stacking. The advantage of this design is attractive in producing electron bunch with low initial emittance and high uniformity along the electron bunch. However, some unavoidable modulations are generated along the laser pulse which trigger the electron bunch modulation generated at the source, which is due to the fast response time (tens of femtosecond) of copper cathode. In order to eliminate the modulation of electron bunch, temporal Gaussian driver laser was designed and tested, measurement results show the electron bunch longitudinal modulation was removed. In this paper, we present two kinds of driver laser pulse temporal shaping methods based on α-BBO stacking and UV grating pair shaping. Moreover, corresponding electron bunch temporal profile are also presented.
	Poster TUPAB121 [2.469 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB121
About •	paper received ※ 19 May 2021 paper accepted ※ 02 June 2021 issue date ※ 25 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPAB285	High Resolution Arrival Time Measurement of the Seed Laser	3320
	J.G. Wang, H.X. Deng, L. Feng, C.L. Li, B. Liu SARI-CAS, Pudong, Shanghai, People’s Republic of China X.T. Wang, W.Y. Zhang Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China
	The Shanghai soft X-ray Free-Electron Laser facility (SXFEL) is a fourth-generation linac-based light source, capable of producing X-ray pulses with a duration of tens of femtosecond. The seed laser for external seeding FEL, therefore, has tight requirements for relative arrival time to the electron bunch. To reach the required energy and wavelength for external seeding FEL, further optical amplification and frequency conversion is needed. These include reflection and propagation in different material and in air, in addition, also include the long laser transport beamline to the undulator, make the laser pulses arrival time influenced by environmental variation. To reach the required specification, high-resolution measurement of the laser arrival time is necessary. In this paper, we present a general concept for the measurement of the laser arrival time.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB285
About •	paper received ※ 19 May 2021 paper accepted ※ 12 July 2021 issue date ※ 12 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPAB286	Design of the Laser-to-RF Synchronization at 1.3 GHz for SHINE	3323
	J.G. Wang, H.X. Deng, L. Feng, C.L. Li, B. Liu SARI-CAS, Pudong, Shanghai, People’s Republic of China X.T. Wang, W.Y. Zhang Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China
	A next-generation photo-science facility like Shanghai HIgh repetition rate XFEL aNd Extreme light facility (SHINE) is aiming to generate femtosecond X-ray pulses with unprecedented brightness to film chemical and physical reactions with sub-atomic level spatio-temporal resolution. To fulfill this scientific goal, high-precision timing synchronization is essential. The pulsed optical synchronization has become an indispensable scheme for femtosecond precision synchronization of X-ray free-electron lasers. One of the critical tasks of pulsed optical synchronization is to synchronize various microwave sources. For the future SHINE, ultralow-noise pulses generated by a mode-locked laser are distributed over large distances via stabilized fiber links to all critical facility end-stations. In order to achieve low timing jitter and long-term stability of 1.3 GHz RF reference signal for the accuracy Low-Level RF(RF) field control, an Electro-optical intensity Modulator (EOM) based scheme is being developed at SHINE. In this paper, we present the progress on the design of the optical part and the integrated electronics of the laser-to-RF synchronization.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB286
About •	paper received ※ 20 May 2021 paper accepted ※ 12 July 2021 issue date ※ 28 August 2021
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THPAB313	Drive Laser System for Shanghai Soft X-Ray Free Electron Laser	4403
	L. Feng, C.L. Li, B. Liu, J.G. Wang SARI-CAS, Pudong, Shanghai, People’s Republic of China X. Lu ANL, Lemont, Illinois, USA X.T. Wang, W.Y. Zhang Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China
	In this paper, we introduce the design and layout of the drive laser of Shanghai Soft X-ray Free Electron Laser (SXFEL). It is known that the temporal and spatial distribution of the drive laser is crucial for high-quality electron beams. The drive laser provides the laser pulse of 266nm wavelength and 8ps pulse duration for the photocathode, as well as 400nm wavelength, 2-20ps tunable pulse duration for the laser heater. For this purpose, there are mainly four parts in such system, including a third-harmonic generation device, pulse stretcher, image transmitted system, and laser optical module for laser heater. Finally, the measured results of the electron beam under this drive laser system are presented and discussed.
	Poster THPAB313 [0.691 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB313
About •	paper received ※ 20 May 2021 paper accepted ※ 15 July 2021 issue date ※ 24 August 2021
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THPAB314	Development of the Femtosecond Timing Distribution System for the Shanghai Soft X-Ray Free Electron Laser	4406
	L. Feng, C.L. Li, B. Liu, J.G. Wang SARI-CAS, Pudong, Shanghai, People’s Republic of China X.T. Wang, W.Y. Zhang Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China
	High accuracy timing and synchronization system on femtosecond timescale play an important role for free-electron laser projects such as Shanghai Soft X-ray free-electron laser facility (SXFEL), and future Shanghai high repetition rate XFEL and Extreme light facility (SHINE). To meet the high precision synchronization requirements for both facilities, an optical-based timing distribution system is absolutely necessary. Such a system distributes the laser pulse train from a locked optical master oscillator through the fiber links, which stabilized by a balance optical cross-correlator based on a periodical-poled KTiOPO4 crystal. In this paper, the recent progress and experimental results of SXFEL and SHINE timing distribution system will be reported.
	Poster THPAB314 [0.351 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB314
About •	paper received ※ 20 May 2021 paper accepted ※ 15 July 2021 issue date ※ 22 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

The Status of a Grating Monochromator for Soft X-Ray Self-Seeding Experiment at SHINE

1532

K.Q. Zhang
SSRF, Shanghai, People’s Republic of China
H.X. Deng, C. Feng, B. Liu, T. Liu
SARI-CAS, Pudong, Shanghai, People’s Republic of China

The research status of a grating monochromator for soft X-ray self-seeding experiment at SHINE has been presented in this paper. The monochromator system includes the vacuum cavity, optical elements, and mechanical movement devices. Until now, the vacuum cavity has finished the manufactured process completely, the optical mirrors have finished machining and measured by the longitudinal trace profiler (LTP) and atomic force microscope (AFM). To make sure the monochromator system can achieve an optical resolution of 1/10000 at the photon energy of 700-1300eV, the system has been integrated and tested recently. In this year, the previous online experiment will be performed in the shanghai soft X-ray free-electron laser (FEL) user facility.

Poster TUPAB072 [0.717 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB072

About •

paper received ※ 11 May 2021 paper accepted ※ 09 June 2021 issue date ※ 01 September 2021

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

TUPAB073

The Design of EEHG Cascaded Harmonic Lasing for SXFEL User Facility

1536

K.Q. Zhang, C. Feng
SSRF, Shanghai, People’s Republic of China
H.X. Deng, B. Liu, T. Liu
SARI-CAS, Pudong, Shanghai, People’s Republic of China

The preliminary design and simulation results of EEHG cascaded harmonic lasing for the SXFEL user facility have been presented in this paper. Using the basic seeded beamline of the SXFEL user facility, the designed parameters are optimized to obtain full coherent FEL output at the 90th harmonic of a 265 nm seed laser. According to the designed parameters and the layout of the SXFEL user facility, the detailed simulations are carried out, the results show that the seeded beamline of the SXFEL user facility can generate 2.93 nm full coherent radiation by the proposed method, which indicates that the method can extend the photon energy range of a seeded FEL and the method can be achieved at the SXFEL user facility.

Poster TUPAB073 [0.955 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB073

About •

paper received ※ 11 May 2021 paper accepted ※ 10 June 2021 issue date ※ 27 August 2021

Export •

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

TUPAB078

Relative Timing Jitter Effects on Two-stage Seeded FEL at SHINE

1551

H.X. Yang
SINAP, Shanghai, People’s Republic of China
H.X. Deng, B. Liu, D. Wang, K.S. Zhou
SARI-CAS, Pudong, Shanghai, People’s Republic of China

Funding: The National Key Research and Development Program of China (Grants No. 2016YFA0401901, No. 2018YFE0103100) and the National Natural Science Foundation of China (Grants No. 11935020, No. 11775293).
The synchronization between the ultrashort electron beam and external seed laser is essential for seeded FELs, especially for a multi-stage one. In this paper, we demonstrate a simple method to obtain the correlations between the pulse energy and relative timing jitter for evaluating the corresponding effects. In this method, the sensitivity of the output FEL performance against electron beam properties is demonstrated by scanning the electron beam and seed lasers, and the fitted curve is used to predict the pulse energy in different timing jitter by random sampling. The results indicate that the pulse energy of the first-stage EEHG is more stable than the second-stage HGHG. Meanwhile, the rise of bunch charge from 100 pC to 300 pC can reduce the timing control requirement by a factor of least 3 for the RMS timing jitter in our numerical simulations based on the parameters of Shanghai High-Repetition-Rate XFEL and Extreme Light Facility. The timing jitter study can demonstrate the feasibility of the EEHG-HGHG cascading scheme in different current profiles for generating Fourier-transform-limited soft X-ray FEL.

Poster TUPAB078 [0.866 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB078

About •

paper received ※ 11 May 2021 paper accepted ※ 11 June 2021 issue date ※ 21 August 2021

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

TUPAB080

Design and Status of the Beam Switchyard of the Shanghai Soft X-Ray FEL User Facility

1559

S. Chen, R. Wang
SSRF, Shanghai, People’s Republic of China
H.X. Deng, C. Feng, X. Fu, B. Liu
SARI-CAS, Pudong, Shanghai, People’s Republic of China

SXFEL-UF, a soft X-ray FEL user facility located in Shanghai, has been upgraded from the existing test facility. Electron energy increases from 840 MeV to 1.5 GeV and a SASE FEL line will be added besides the existing seeding FEL line. It has started commissioning since early this year. In order for simultaneous operation of the two FEL lines, a beam switchyard is built between the linac and the two FEL lines. In this paper, the physics design of the beam switchyard is described.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB080

About •

paper received ※ 19 May 2021 paper accepted ※ 11 June 2021 issue date ※ 20 August 2021

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TUPAB089

Proof-of-Principle Experiment Design for PEHG-FEL in SXFEL User Facility

1589

Z. Qi, H.X. Deng, C. Feng, B. Liu
SARI-CAS, Pudong, Shanghai, People’s Republic of China
S. Chen, Z.T. Zhao
SSRF, Shanghai, People’s Republic of China

In this paper, we demonstrate a proof-of-principle experimental design for phase-merging enhanced harmonic generation (PEHG) free electron laser (FEL) in Shanghai Soft X-ray Free Electron Laser (SXFEL) user facility. The simulation results indicate that, taking advantage of the beam switchyard, the normal modulator and the seeded FEL line in SXFEL user facility, together with an oblique incident seed laser, we can perform the phase-merging effect in PEHG and finally get an 8.86nm FEL radiation through the undulator, which is the 30th harmonic of the seed laser.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB089

About •

paper received ※ 19 May 2021 paper accepted ※ 17 June 2021 issue date ※ 02 September 2021

Export •

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

TUPAB121

Photoinjector Drive Laser Temporal Shaping for Shanghai Soft X-Ray Free Electron Laser

1674

C.L. Li, X.T. Wang, W.Y. Zhang
Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China
X.L. Dai
SSRF, Shanghai, People’s Republic of China
H.X. Deng, L. Feng, B. Liu, J.G. Wang
SARI-CAS, Pudong, Shanghai, People’s Republic of China

Shanghai soft X ray free electron laser (SXFEL) initial designed shape of the photocathode driver laser is flattop produced by α-BBO stacking. The advantage of this design is attractive in producing electron bunch with low initial emittance and high uniformity along the electron bunch. However, some unavoidable modulations are generated along the laser pulse which trigger the electron bunch modulation generated at the source, which is due to the fast response time (tens of femtosecond) of copper cathode. In order to eliminate the modulation of electron bunch, temporal Gaussian driver laser was designed and tested, measurement results show the electron bunch longitudinal modulation was removed. In this paper, we present two kinds of driver laser pulse temporal shaping methods based on α-BBO stacking and UV grating pair shaping. Moreover, corresponding electron bunch temporal profile are also presented.

Poster TUPAB121 [2.469 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB121

About •

paper received ※ 19 May 2021 paper accepted ※ 02 June 2021 issue date ※ 25 August 2021

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

WEPAB285

High Resolution Arrival Time Measurement of the Seed Laser

3320

J.G. Wang, H.X. Deng, L. Feng, C.L. Li, B. Liu
SARI-CAS, Pudong, Shanghai, People’s Republic of China
X.T. Wang, W.Y. Zhang
Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China

The Shanghai soft X-ray Free-Electron Laser facility (SXFEL) is a fourth-generation linac-based light source, capable of producing X-ray pulses with a duration of tens of femtosecond. The seed laser for external seeding FEL, therefore, has tight requirements for relative arrival time to the electron bunch. To reach the required energy and wavelength for external seeding FEL, further optical amplification and frequency conversion is needed. These include reflection and propagation in different material and in air, in addition, also include the long laser transport beamline to the undulator, make the laser pulses arrival time influenced by environmental variation. To reach the required specification, high-resolution measurement of the laser arrival time is necessary. In this paper, we present a general concept for the measurement of the laser arrival time.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB285

About •

paper received ※ 19 May 2021 paper accepted ※ 12 July 2021 issue date ※ 12 August 2021

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

WEPAB286

Design of the Laser-to-RF Synchronization at 1.3 GHz for SHINE

3323

J.G. Wang, H.X. Deng, L. Feng, C.L. Li, B. Liu
SARI-CAS, Pudong, Shanghai, People’s Republic of China
X.T. Wang, W.Y. Zhang
Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China

A next-generation photo-science facility like Shanghai HIgh repetition rate XFEL aNd Extreme light facility (SHINE) is aiming to generate femtosecond X-ray pulses with unprecedented brightness to film chemical and physical reactions with sub-atomic level spatio-temporal resolution. To fulfill this scientific goal, high-precision timing synchronization is essential. The pulsed optical synchronization has become an indispensable scheme for femtosecond precision synchronization of X-ray free-electron lasers. One of the critical tasks of pulsed optical synchronization is to synchronize various microwave sources. For the future SHINE, ultralow-noise pulses generated by a mode-locked laser are distributed over large distances via stabilized fiber links to all critical facility end-stations. In order to achieve low timing jitter and long-term stability of 1.3 GHz RF reference signal for the accuracy Low-Level RF(RF) field control, an Electro-optical intensity Modulator (EOM) based scheme is being developed at SHINE. In this paper, we present the progress on the design of the optical part and the integrated electronics of the laser-to-RF synchronization.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB286

About •

paper received ※ 20 May 2021 paper accepted ※ 12 July 2021 issue date ※ 28 August 2021

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

THPAB313

Drive Laser System for Shanghai Soft X-Ray Free Electron Laser

4403

L. Feng, C.L. Li, B. Liu, J.G. Wang
SARI-CAS, Pudong, Shanghai, People’s Republic of China
X. Lu
ANL, Lemont, Illinois, USA
X.T. Wang, W.Y. Zhang
Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China

In this paper, we introduce the design and layout of the drive laser of Shanghai Soft X-ray Free Electron Laser (SXFEL). It is known that the temporal and spatial distribution of the drive laser is crucial for high-quality electron beams. The drive laser provides the laser pulse of 266nm wavelength and 8ps pulse duration for the photocathode, as well as 400nm wavelength, 2-20ps tunable pulse duration for the laser heater. For this purpose, there are mainly four parts in such system, including a third-harmonic generation device, pulse stretcher, image transmitted system, and laser optical module for laser heater. Finally, the measured results of the electron beam under this drive laser system are presented and discussed.

Poster THPAB313 [0.691 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB313

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paper received ※ 20 May 2021 paper accepted ※ 15 July 2021 issue date ※ 24 August 2021

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

THPAB314

Development of the Femtosecond Timing Distribution System for the Shanghai Soft X-Ray Free Electron Laser

4406

L. Feng, C.L. Li, B. Liu, J.G. Wang
SARI-CAS, Pudong, Shanghai, People’s Republic of China
X.T. Wang, W.Y. Zhang
Shanghai Advanced Research Institute, Pudong, Shanghai, People’s Republic of China

High accuracy timing and synchronization system on femtosecond timescale play an important role for free-electron laser projects such as Shanghai Soft X-ray free-electron laser facility (SXFEL), and future Shanghai high repetition rate XFEL and Extreme light facility (SHINE). To meet the high precision synchronization requirements for both facilities, an optical-based timing distribution system is absolutely necessary. Such a system distributes the laser pulse train from a locked optical master oscillator through the fiber links, which stabilized by a balance optical cross-correlator based on a periodical-poled KTiOPO4 crystal. In this paper, the recent progress and experimental results of SXFEL and SHINE timing distribution system will be reported.

Poster THPAB314 [0.351 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB314

About •

paper received ※ 20 May 2021 paper accepted ※ 15 July 2021 issue date ※ 22 August 2021

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