Design and R&D progress of the Shanghai Deep UV(SDUV) FEL

Transcription

1 Design and R&D progress of the Shanghai Deep UV(SDUV) FEL Dong Wang for SDUV team, Shanghai Inst of Applied Physics (SINAP), Chinese Academy of Sciences, Shanghai, China FEL2009, August 24, 2009 Liverpool, UK

2 Shanghai Institute of Applied Physics (SINAP) : two campuses 1 hour drive SDUV is at old campus of SINAP. New campus hosts 3.5 GeV SSRF future X-ray FELs

3 Brief history of FEL activities at SINAP 1998: proposal of a medium energy light source, R&D starts (100 MeV prototype linac, etc) 2001: SSRF project pending, proposal for a DUV FEL test bed : FEL activities slowed due to the 3.5 GeV light source construction : photo-injector commissioning. location of a soft X-ray FEL decided to be at SINAP 2009: installation of FEL components. SDUV is starting to run now

4 Located in old campus DUV FEL test bed in SINAP Based on an existing proto-type linac injector for the light source Photo-injector and linac ready for beam Now most hardware ready for single stage HGHG. First FEL in 2009

5 100 MeV linac prototype for light source Parameters Unit Single bunch Multi bunch Energy MeV Energy spread (rms) Normlized emittance (rms) Pulse length(fwhm) % /0.5 mm mrad /80 ns /175 Beam current (rms) ma 1280 (peak) 323/292 (peak) Linac was commissioned in running Compton backscattering experiments, etc.

6 Main parameters for Shanghai Deep UV FEL Electron beam: E = 160 MeV, Ip > 300 A,ε < 6.0 mm-mrad, energy spread< 0.02%, bunch length: 2~3 ps Seed laser: λs=786nm(1047nm),τ=100fs(a few ps), Ps : 1~100 MW Modulators: stage-1 stage-2 λu (mm) a u Lm (m) Radiators: stage-1 stage-2 λu (mm) a u Lr(m) 9 9 β (m) 3 3 λ-fel(nm)

7 SDUV, Phase-I I and phase-ii Phase-I: SASE, Single-stage HGHG, EEHG 262nm R 1047nm M Phase-II: Cascaded two-stage HGHG 131nm R 262nm M 262nm R nm M

8 Upgrade to 160 MeV 100kV-ns grid gun and 15 MeV buncher of the existing 100MeV Linac replaced by a 40MeV injector consisting of photo-cathode rf gun and an accelerating section. RF photo injector

9 Drive Laser system for photocathode RF gun Jaguar-QCW-1000 Laser (+FHG) and Synchronizer CLX-1100 (Switzerland Time-Bandwidth Products,Inc) has been chosen Commissioning since 2007 Main parameters Laser medium Nd:YLF Wavelength: 1047nm/262nm Pulse length: 10ps/8ps Repetition frequency: 0~100Hz Energy/pulse: 1mJ/0.25mJ Energy stability(p-p): 1%rms Time stability: <0.5ps rms

10 Seed laser parameters Drive laser (as seed laser too) Dedicated seed laser (by end of 2009) Type Nd-YLF Ti:Sa Wavelength 1047 / 262 nm 786 / 262 nm Pulse energy 1.2mJ / 0.2mJ 4mJ / 0.4mJ Pulse duration 8-10 ps 1ps/100fs/30fs Power as IR seed ~20MW(split) 3~100 GW Company Time-bandwidth Coherent Repetition rate_max. 100 Hz 100 Hz Bandwidth ~0.1nm ~10nm Pulse shapes Gaussian Gaussian Energy stability <2% <2%

11 Photo-injector on test bench at 2008

12 光 Photo gun commissioning 固定靶, 外形尺寸由束测组提供 分析磁铁 四极磁铁 OTR/ YAG, 外形尺寸由束测组提供 Grad.: 100 MV/m, E: ~4 MeV, Bunch Charge: emit: ~ 5mm.mrad Charge(pC) peak(pc) 30deg(pC) E_cath(MV/m)

13 Bunch compressor Main parameters Beam energy: 100 MeV Bunch length: 8~9 / 2~3ps Compression ratio:2~3 Bend angle: 7 ~ 14 Maximum field:4000 Gs R 56 (Max.): -100 mm Installed in linac this summer

14 FEL layout (August, 2009) Laser seeds are 1047nm in nm/262nm seeds come soon. Seed 2 Seed 1 Radiator Modulator 2 Modulator 1 Chicane 2 Chicane 1

15 Newly designed dual-modulator section Dispersion section Dispersion R56_max: section ~5mm Laser inj. chicane R56_max: ~40mm Laser injection 1 e- beam PM modulator 5cm, variable gap Laser injection 2 EM modulator 6.5cm, under construction Goals: Double modulators Double chicanes(r56) Double lasers, etc. Capabilities of doing a set of FEL experiments: dual-modulator type, dual-laser type, etc. E. Allaria and G. De Ninno, PRL 99, (2007) Q. Jia, APL 93, (2008) G. Stupakov, PRL (2009)

16 Undulator System: Radiator: 6x1.5m sections are made and installed Main parameters Period length 25mm Gap 10mm Peak Field 0.6T K 1.4 Type hybrid/nd-fe-b Segment length mm Space between segments 250mm Segment number 6 First field integral 0.1T-mm Second field integral 10T-mm*mm

17 New 10x6.5cm EM undulator as 2nd modulator (1st modulator is 5cm PM)

18 August 2009 Injector + linac: RF conditioning. Ready for beam. Photo injector Linac FEL Radiator FEL section: Installations continue.

19 Experiment programs on SDUV SASE at 262 nm HGHG at 262 nm. other FEL experiments (ECHO etc.) cascaded HGHG (262 nm 131 nm, need new undulators) Schedule: 2008: commissioning of photo gun 2009: Sept.-Oct., accelerator commissioning, Since Nov.?, FEL experiments : cascading HG

20 Summary The Free Electron Laser will be the next focus in SINAP after the 3.5GeV light source. The DUV FEL test bed starts commissioning, ready for FEL experiments in late 2009, capable of running HGHG and EEHG, etc. Acknowledgement: Z.T. Zhao, Z.M. Dai, M.H. Zhao, Q. Gu, Q.G. Zhou, K.R. Ye, J.H. Chen Y.Z. Chen, H.X. Deng, X. F. Zhao, D.H. He*, Q.K. Jia*, S. C. Zhang*, S.Y. Chen#, J. P. Dai#, J.R. Zhang#, G.. X. Pei#, C.X. W. H. D.C. Shanghai Institute of Applied Physics, Shanghai , *University of Science and Technology of China, Hefei #Instittue of High Energy Physics, Beijing University, Beijing ,

21 Thanks for your attention!

22 Shanghai Soft- and Hard X-ray X FEL: layout