12/28-29/2004ILC Workshop/ PAL General Idea on ILC Beam Diagnostics Jung Yun Huang Heung-Sik Kang PALPOSTECH

12/28-29/2004ILC Workshop/ PAL Tesla parameters

12/28-29/2004ILC Workshop/ PAL Tesla IP parameters

12/28-29/2004ILC Workshop/ PAL Most critical measurements for Linear Collider  nanometer beam position measurement near IP (σ z ~ nm) -best cavity BPM (cBPM) ~ 25 nm -best stripline BPMs (sBPM)~ 1 μm  nanometer beam size measurement at IP - best laser wire scan ~100 nm - best metal wire scan ~ 5 μm - laser interference slit scan ~ 50 nm (Shintake) resolution limited by wavelength  fs bunch length measurement - electro-optic/ CSR, CTR/ rf deflector ~30 fs  Various techniques for PAL XFEL will be also applicable for ILC Requirements and Status of ILC Diagnostics

12/28-29/2004ILC Workshop/ PAL BPM reqiuements -Resolution relates with - beam pipe diameter (smaller, better signal/noise) cold system  larger diameter - bunch charge -1 - environmental factors (temperature, vibrations, …) - ILC Resolution requirements ~ 5 main linac ~ < BDS -Stability requirements - offset drift ~100 nm for many minutes - special support system - temperature and vibration control

12/28-29/2004ILC Workshop/ PAL Cavity BPM 1 -Pill-box shaped cavity BPM model - δx ~ dipole mode field V 110 (δx)

12/28-29/2004ILC Workshop/ PAL Cavity BPM 2 -TM010 monopole field : subtraction of pickup antenna signals or magnetic coupler for damping - For single bunch measurement, lower Q<1000 for faster response Nano-alignment setup With resolution of ~ few nm M. Ross, et. al (SLAC, BINP, KEK) 1.6mV/μm/nC

12/28-29/2004ILC Workshop/ PAL BPM signal processor -Digital Signal processing -Digital processor developed in Swiss Light Source -Maximum signal/noise by removing active/passive analog devices -Full software processing (I/Q) : easy tunability

12/28-29/2004ILC Workshop/ PAL Beam size (Nano wire) ~120nm resolution Laser wire scan in ATF

12/28-29/2004ILC Workshop/ PAL Nano wire monitor Schematic compact nano wire setup for ILC: M. Ross (SLAC)

12/28-29/2004ILC Workshop/ PAL  In ILC/XFEL electron beam duration down to femto second (fs) scale  use secondary photon for bunch length measurements (interferometry) -Coherent transition radiation (CTR): < FIR -Coherent synchrotron radiation (CSR): < FIR  use transverse rf kick for beam streaking -rf zero-phasing -Rf deflecting cavity (rf streak camera) fs electron-beam measurement

12/28-29/2004ILC Workshop/ PAL  Transition radiation -Radiation emitted when e-beam crosses dielectric boundary -Backward and forward TR (mm  ~ plasma freq.) -Coherent TR when bunch length  wavelength (FIR) Transition Radiation I max at  ~ 1/ 

12/28-29/2004ILC Workshop/ PAL Rf Deflector - Use fast rf deflector for e-beam streaking - resolution down to femto-second range

12/28-29/2004ILC Workshop/ PAL Rf stretcher (0-phasing)  zero-phasing -Energy chirping by rf (cf: Fast streak by electric pulse) -Dispersion in bending magnet -dE  dX  dT -Resolution ~ 10fs possible

12/28-29/2004ILC Workshop/ PAL Rf stretcher II  Example: microbunching at BNL DUVFEL (50fs micro bunches)

12/28-29/2004ILC Workshop/ PAL Electro-Optic method  EO effect -Large electric field enhances higher order refractive index -e.g. Pockels effect: n(E), Kerr effect: n(E 2 ) - use probe laser to detect polarization modulation

12/28-29/2004ILC Workshop/ PAL Electro-optic method I  Example application in accelerator: single shot with chirped beam FELIX in Netherland + CCD

12/28-29/2004ILC Workshop/ PAL Electro-Optic method II  snapshot of bunch shape : proposed in collaboration with BNL-ATF

12/28-29/2004ILC Workshop/ PAL Electro-optic method III  Cross-correlation method : proposed in collaboration with BNL-ATF

12/28-29/2004ILC Workshop/ PAL Quantity of ILC Monitors BPM Beam Profile(size) Bunch Length Beam sources Linac220024? Damping Ring Beam Delivery system 300?8

12/28-29/2004ILC Workshop/ PAL Laser wire collaboration

12/28-29/2004ILC Workshop/ PAL Suggestion for successful contribution to ILC PAL-XFEL diagnostic technology can be extended for ILC with appropriate research supports from PAL-XFEL Collaboration with advanced Labs (KEK, TESLA, SLAC) Support graduate students (multidisciplinary graduate school in PAL?) PAL XFEL as a test facility for ILC Existing nanoBPM collaboration

12/28-29/2004ILC Workshop/ PAL Major parameters InjectorBCUndulatorRemarks Beam Energy150 MeV442 MeV3,000 MeV Beam Charge1.0 nC 0.1% 1 pC Bunch Length900 μm (3 ps)110 μm (300 fs)25 μm (80 fs) σ z rms 3μm (10fs) Beam Size(135, 125) μm(115, 100) μm(68, 62) μm (σ x, σ y ) 5μm Beam Emittance1.0 μm ~1.0 μm10% Beam position ∓ 10 μm ∓ 2 μm Beam parameters for PAL-XFEL diagnostics

12/28-29/2004ILC Workshop/ PAL MonitorQuantityLocationRemarks Bunch length I ( >1ps) 3Injector, BC1, BC2Streak Camera Bunch length II (< 1ps) 5 BC1, BC2 1.2GeV Linac, 3GeV Linac CTR/CSR, EO crystal rf deflector Beam size30XFEL Linac / UndulatorOTR, SR, wire monitor Beam emittance7 injector, BC1, BC2 1.2GeV Linac, 3GeV Linac OTR + Quad. Magnet 0-phasing (Slice emittance) Beam charge16XFEL Linac / UndulatorICT Beam energy Energy spread 8 BC1, BC2 1.2GeV Linac FEL 1, FEL 2 3GeV Linac, FEL 3 OTR at dispersive section Beam position60 +XFEL Linac / UndulatorStripline, Cavity BPM, OTR screen X-ray intensity10UndulatorCrystal diffractor + PIN diode Diagnostic Monitors for PAL XFEL