The LCLS LCLS X X- -Ray FEL and Ray FEL and The Related R&D - PowerPoint PPT Presentation

The LCLS LCLS X X- -Ray FEL and Ray FEL and The Related R&D at the SPPS Related R&D at the SPPS TJNAF TJNAF January 30, 2004 January 30, 2004 P. Emma, SLAC P. Emma, SLAC Sub- -Picosecond Pulse Source Picosecond Pulse Source Sub Sub-Picosecond Pulse Source

Linac Coherent Light Source ( LCLS LCLS ) ) Linac Coherent Light Source ( new RF- new RF -gun at 2 gun at 2- -km point km point new RF-gun at 2-km point th - 4 th -Generation Generation X -ray SASE ray SASE 4 X - FEL Based on SLAC SLAC Linac Linac FEL Based on new bunch compressors new bunch compressors new bunch compressors SASE radiation at 1.5 Å SASE radiation at 1.5 Å SASE radiation at 1.5 Å • 14 • 14- -GeV electrons GeV electrons µ m emittance - µ • 1.2 1.2- m emittance • • 200 200- -fsec FWHM pulse fsec FWHM pulse • 33 peak brightness × 10 2 × * • 2 10 33 peak brightness * • 120- -m undulator in research yard m undulator in research yard 120 120-m undulator in research yard * photons/sec/mm 2 2 /mrad /mrad 2 2 /0.1% /0.1%- -BW BW * photons/sec/mm

Stanford Synchrotron Radiation Laboratory Linac Coherent Light Source Stanford Linear Accelerator Center LCLS - - Estimated Cost, Schedule Estimated Cost, Schedule LCLS LCLS - Estimated Cost, Schedule $220M-$260M Total Estimated Cost range $265M-$315M Total Project Cost range FY2005 Long-lead purchases for injector, undulator FY2006 Construction begins FY2007 FEL Commissioning begins September 2008 Construction complete – operations begins CD- -2b 2b XFEL XFEL CD Title I Title I CD- -1 1 CD CD- -2a 2a CD CD- CD -0 0 CD- -3b 3b CD Commissioning Commissioning Design Design Complete Complete FY2001 FY2002 FY2003 2002 2003 FY2004 2004 FY2005 2005 FY2006 2006 FY2007 FY2008 FY2009 FY2001 FY2002 FY2003 2002 2003 FY2004 2004 FY2005 2005 FY2006 2006 FY2007 FY2008 FY2009 Construction Operation Operation CD- -3a 3a CD CD- -4 4 CD J. Galayda J. Galayda

LCLS – – Current Layout and Future Expansion Capacity Current Layout and Future Expansion Capacity LCLS LCLS – Current Layout and Future Expansion Capacity Transport Transport Undulator Undulator Hall A Hall A Tunnel Tunnel Hall B Hall B 3 Beams/mirror 3 Beams/mirror Expansion Expansion J. Galayda J. Galayda

Coulomb Explosion of Lysozyme (50 fs) Coulomb Explosion of Lysozyme (50 fs) Atomic and Atomic and molecular molecular dynamics occur dynamics occur at the fsec -scale scale at the fsec - J. Hajdu J. Hajdu

− bunch at Chicane Center Exploit Position Time Correlation on Correlation on e e − bunch at Chicane Center Exploit Position- -Time 0.1 mm (300 fs) rms 0.1 mm (300 fs) rms , horizontal pos. (mm) x , horizontal pos. (mm) 50 µ µ m m 50 2.6 mm rms 2.6 mm rms Access to time Access to time coordinate coordinate along bunch along bunch x , longitudinal position (mm) z , longitudinal position (mm) z LCLS BC2 bunch compressor chicane BC2 bunch compressor chicane LCLS (similar in other machines) (similar in other machines)

Add thin slotted foil in center of chicane Add thin slotted foil in center of chicane y y coulomb coulomb − e − scattered e scattered − e − − e − e unspoiled e unspoiled coulomb coulomb − e − scattered e scattered 2∆ x 2∆ x ∝ ∝ ∆ ∆ E ∝ t E ∝ x / E E / t x µ m thick Be foil - µ 15- m thick Be foil 15 P. Emma, M. Cornacchia, K. Bane, Z. Huang, H. Schlarb (DESY), G. Stupakov, D. Walz, Stupakov, D. Walz, PRL P. Emma, M. Cornacchia, K. Bane, Z. Huang, H. Schlarb (DESY), G. PRL

Track 200k macro- Track 200k macro -particles through entire particles through entire LCLS LCLS up to 14.3 GeV up to 14.3 GeV 200 fs 200 fs ∆ E ∆ / E E / E

≈ 60 m 60 m z ≈ z 2 fs fwhm 2 fs fwhm Power Power -ray ray x - x Genesis 1.3 FEL code FEL code Genesis 1.3 Power (GW) Power (GW)

Micro- -Bunching Instabilities Bunching Instabilities Micro − beams (small e − ε and beams (small ε ” e FEL instability needs very “ cold cold ” and E -spread) spread) FEL instability needs very “ E - Such a cold beam is subject to other “undesirable” instabilities in the Such a cold beam is subject to other “undesirable” instabilities in the accelerator ( CSR CSR , Longitudinal Space , Longitudinal Space- -Charge= Charge= LSC LSC , wakefields) , wakefields) accelerator ( current modulation current modulation Gain=10 Gain=10 1% 10% 1% 10% Z ( k ) t t LCLS simulations simulations LCLS (M. Borland) (M. Borland) Saldin, Saldin, Saldin, Schneidmiller, Schneidmiller, Schneidmiller, Yurkov Yurkov Yurkov

How cold is the photo- -injector beam? injector beam? How cold is the photo Parmela Simulation Parmela Simulation TTF measurement TTF measurement 3 keV 3 keV H. Schlarb, M. Huening H. Schlarb, M. Huening E / E E / ∆ E simulation ∆ simulation measured measured ∆ t ∆ t (sec) (sec) × 36 ⇒ 3 keV, accelerated to 14 GeV, and compressed × 36 ⇒ 3 keV, accelerated to 14 GeV, and compressed × 10 × 36 < × 10 3/14 × 10 6 6 × 36 < 1 1 × 10 − − 5 3/14 5 × 10 1 × − 4 10 − 4 ) Too small to be useful in FEL (no effect on FEL gain when < 1 ) Too small to be useful in FEL (no effect on FEL gain when <

Laser Heater for Landau Damping Laser Heater for Landau Damping 800 nm, 1.2 MW 800 nm, 1.2 MW 50 cm 50 cm 10 cm 10 cm 2 cm 2 cm θ ≈ ≈ 5.7 θ 10 per. undulator 10 per. undulator 5.7º º 10 cm 10 cm ~120 cm ~120 cm Laser- -electron interaction in undulator induces energy electron interaction in undulator induces energy Laser ⇒ 40 keV rms modulation (at 800 nm) ⇒ 40 keV rms modulation (at 800 nm) Inside weak chicane for laser access and time- -coordinate coordinate Inside weak chicane for laser access and time smearing (Emittance growth negligible) smearing (Emittance growth negligible) Z. Huang, M. Borland (ANL), P. Emma, J. Wu, R. Carr, Z. Huang, M. Borland (ANL), P. Emma, J. Wu, R. Carr, C. Limborg, G. Stupakov, J. Welch C. Limborg, G. Stupakov, J. Welch

− spot − spot e − e − laser spot much bigger than e spot laser spot similar to e spot laser spot much bigger than laser spot similar to = 37 MW P 0 0 = 37 MW 0 = 1.2 MW = 1.2 MW P P 0 P +60 keV +60 keV ≈ 3 mm 0 ≈ µ m = 350 µ 3 mm m w 0 w w 0 0 = 350 w large laser spot large laser spot matched spot matched spot σ x ≈ 200 µ m σ y ≈ 200 µ σ x σ y ≈ ≈ 200 200 µ µ m m m x , , y x , , y 800 nm 800 nm − 60 keV − 60 keV In Chicane In Chicane In Chicane ∆ σ σ z ≈ 〈 〈 x 〉 1/2 η x nm structure then gets smeared by chicane: ∆ z ≈ 2 〉 | η � >> � 1/2 | 800- -nm structure then gets smeared by chicane: ' 2 | >> 800 x ' x | large spot large spot 0.015 1 0.01 keV small spot small spot 0.005 V 40 keV rms 40 keV rms 0 50 0 50 0 mc 2 keV

µ m, = 350 µ The GOOD ( ( w m, P = 1.2 MW), the BAD ( ( w = 3 mm, P = 37 MW), The GOOD w 0 0 = 350 P 0 0 = 1.2 MW), the BAD 0 = 3 mm, 0 = 37 MW), w 0 P 0 small spot double- -horn horn small spot double Final long. phase Final long. phase no heater no heater space at 14 GeV for space at 14 GeV for µ m, 1% seed - µ initial 15- m, 1% seed initial 15 and and the UGLY (no heater) the UGLY (no heater)

Sliced final Sliced final FEL Power Gain Length 6 energy spread in energy spread in FEL at 14 GeV FEL at 14 GeV 5 λ 0 µ m, ∆ I/I λ = 15 µ m, ∆ = 1% 0 = 15 I/I 0 0 = 1% Ming Xie scaling Ming Xie scaling 4 18 0 1 2 3 4 18 Σ ∆ f � 10 4 16 16 14 14 (a) No heater No heater (a) σ E / E 0 ( × 10 4 ) 12 σ E / E 0 ( × 10 4 ) 12 (a) (a) 10 10 (b) w = 3 mm, (b) 0 = 3 mm, w 0 8 8 = 37 MW P 0 0 = 37 MW P 6 6 4 µ m, = 350 µ 4 (c) w m, (c) 0 = 350 w 0 (b) 2 (b) 2 = 1.2 MW 0 = 1.2 MW P 0 P (c) (c) 0 0 −40 −20 0 20 40 −40 −20 0 20 40 z ( µ m) to be published in PRSTAB to be published in PRSTAB z ( µ m)

Short Bunch Generation in the SLAC Linac Short Bunch Generation in the SLAC Linac Damping Ring Damping Ring γε ≈ ≈ 30 µ m) ( γε 30 µ m) ( σ z σ z ≈ ≈ 6 mm 6 mm RTL SLAC Linac RTL SLAC Linac FFTB FFTB σ z ≈ 50 µ m σ z ≈ 50 µ 1.1 mm m 1.1 mm 1 GeV 30 GeV σ z ≈ 12 µ m 1 GeV 30 GeV σ z ≈ 12 µ m add 14- -meter chicane compressor meter chicane compressor add 14 add 14-meter chicane compressor in linac at 1/3- -point (9 GeV) point (9 GeV) in linac at 1/3 in linac at 1/3-point (9 GeV) 〈 E 〉 = 28.493 GeV, N e = 2.133 × 10 10 ppb σ E / 〈 E 〉 =1.51% (FWHM: 4.33%) 40 fsec Existing bends compress to 40 fsec 4 4 Existing bends compress to 2 2 ∆ E / 〈 E 〉 /% ∆ E / 〈 E 〉 /% 0 0 ~1.5 Å ~1.5 Å −2 −2 0 0.5 1 1.5 2 0.1 0.2 0.3 n /10 3 z /mm 30 kA 30 kA σ z = 28.0 µ m (FWHM: 24.6 µ m, Gauss: 11.0 µ m) I pk = 30.631 kA 30 25 80 fsec FWHM 80 fsec compression by factor of 500 500 20 compression by factor of FWHM I /kA 15 10 5 0 0.1 0.2 0.3 z /mm P. Emma et al. , PAC’01 P. Emma et al. , PAC’01