Summary of Related Topics from the Miniworkshop on XFEL Short Bunch Measurement and Timing John Arthur LCLS September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected].
Download ReportTranscript Summary of Related Topics from the Miniworkshop on XFEL Short Bunch Measurement and Timing John Arthur LCLS September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected].
Summary of Related Topics from the Miniworkshop on XFEL Short Bunch Measurement and Timing John Arthur LCLS September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] ICFA Future Light Sources Subpanel Miniworkshop on XFEL Short Bunch Measurement and Timing Stanford Linear Accelerator Center, July 26 - 30, 2004 Organizers: J. Hastings, P. Krejcik, H. Schlarb, J. Wu http://www-ssrl.slac.stanford.edu/lcls/xfel2004/index.html September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] This workshop will focus on the issues of measuring and synchronizing ultra-short bunches in linac-based FELs. Three primary themes will be addressed at the workshop: Measurement techniques for the determining the electron bunch length and arrival time. Measurement techniques, theory and simulation for diagnosing spontaneous undulator and XFEL radiation to determine its temporal profile. Issues of timing and synchronization of ultra-fast lasers to the electron bunch and RF. September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] The workshop featured a concise, eccentric history of American baseball P. Emma September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] X-ray diagnostics of FEL performance September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] Simulations show development of FEL beam in undulator W. Fawley September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] Distinctive spectral fluctuations of FEL pulses Typical single-shot spectrum long bunch Average spectrum short bunch V. Sajaev September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] To resolve LCLS spectrum, need single-shot x-ray spectrometer with resolution of 10-6 At 8 keV, Range of dE/E >10-3 possible Resolution of 10-5 possible September 22, 2004 LCLS Diagnostics and Commissioning Workshop D. Peter Siddons Resolution of 10-6 possible with backscattering and asymmetric reflections, but range would be reduced John Arthur [email protected] Discussions of x-ray diagnostics and radiation properties Focused on diagnostics which will help FEL performance Intensity, propagation of pulse shape, spectrum are all important Spectral measurement needs dE/E<10-6 to see spikes Ability to turn off undulator sections is vital Questions: Effect of reflections/aperturing by beam pipe How chirp helps or hurts How to organize data How best to correlate x-ray with optical laser How coherent (spatially) will the LCLS be September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] Electron diagnostics for XFELs September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] Electro-Optic Sampling encodes electron pulse shape on a laser pulse EO Crystal k k k v September 22, 2004 LCLS Diagnostics and Commissioning Workshop v v John Arthur [email protected] time polarizing beamsplitter integrated intensity time time; space klaser integrated intensity September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] 200 m EOS data from SPPS A. Cavalieri Single-Shot w/ high frequency filtering Timing Jitter Data (20 Successive Shots) shot iCCD counts time (ps) color representation September 22, 2004 LCLS Diagnostics and Commissioning Workshop time (ps) John Arthur [email protected] Talks on EOS were given by A. Cavalieri, S. Düsterer, H. Loos, A. Winter, D. Reis, and S. Jamison September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] An interferometer can be used to autocorrelate Coherent Transition Radiation, giving a measure of electron bunch length P. Muggli September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] Electron bunch measurements using a transverse RF deflector P. Emma 2.44 m V(t) e- RF ‘streak’ sy S-band sz V0 20 MV sz 50 m, E 28 GeV bc September 22, 2004 LCLS Diagnostics and Commissioning Workshop D 90° bp John Arthur [email protected] Many other talks discussed aspects of timing jitter measurement and control September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected] General Conclusions Electron diagnostics seem to be more advanced than x-ray diagnostics Need to sharpen the requirements for diagnostics Need to coordinate/share results of experiments Simulations will play a large role What’s up with these Cub fans? September 22, 2004 LCLS Diagnostics and Commissioning Workshop John Arthur [email protected]