IBIC2012 - List of Authors (Frisch, J.C.)

Paper	Title	Page
TUPA41	Ultra-short Electron Bunch and X-ray Temporal Diagnostics with an X-band Transverse Deflecting Cavity	441
	P. Krejcik, Y. Ding, J.C. Frisch, Z. Huang, H. Loos, J.W. Wang, M.-H. Wang SLAC, Menlo Park, California, USA C. Behrens DESY, Hamburg, Germany P. Emma LBNL, Berkeley, California, USA
	Funding: This work was supported by Department of Energy Contract No. DE-AC0276SF00515 The technique of streaking an electron bunch with a RF deflecting cavity to measure its bunch length is being applied in a new way at the Linac Coherent Light Source with the goal of measuring the femtosecond temporal profile of the FEL photon beam. A powerful X-band deflecting cavity is being installed downstream of the FEL undulator and the streaked electron beam will be observed at an energy spectrometer screen at the beam dump. The single-shot measurements will reveal which time slices of the streaked beam have contributed to the FEL process by virtue of their greater energy loss and energy spread relative to the non-lasing portions of the electron bunch. Since the diagnostic is located downstream of the undulator it can be operated continuously without interrupting the beam to the users. The resolution of the new X-band system will be compared to the existing S-band RF deflecting diagnostic systems at SLAC and consideration is given to the required RF phase stability tolerances required for acceptable beam jitter on the monitor. Simulation studies show that about 1 fs (rms) time resolution is achievable in the LCLS over a wide range of FEL wavelengths and pulse lengths.

TUPA44	Status of the LCLS Experiment Timing System	453
	J.C. Frisch, C. Bostedt, R.N. Coffee, A.R. Fry, N. Hartmann, J. May, D.J. Nicholson, S. Schorb, S.R. Smith SLAC, Menlo Park, California, USA
	Funding: Work Supported by Department of Energy Contract DE AC03 76SF00515 X-ray / optical laser pump - probe experiments are used for a significant fraction of the scientific work performed at LCLS. The experimental laser systems are locked to the timing of the electron beam through a combination of RF and optical fiber based systems. The remaining ~100 femtosecond RMS jitter of the X-rays relative to the optical laser is measured shot-to-shot by both a RF timing detector, and by direct X-ray to optical cross-correlation, and the result is used to correct the experiment timing to 10s of femtoseconds. We present the present status of the system and plans for future upgrades.

TUPA47	Middle-infrared Prism Spectrometer for Single-shot Bunch Length Diagnostics at the LCLS	463
	T.J. Maxwell, Y. Ding, A.S. Fisher, J.C. Frisch, H. Loos SLAC, Menlo Park, California, USA C. Behrens DESY, Hamburg, Germany
	Funding: Work supported in part by US Department of Energy contract number DE-AC02-76SF00515. Modern high-brightness accelerators such as laser plasma wakefield and free-electron lasers continue the drive to ever-shorter bunches. At low-charge (< 20 pC), bunches as short as 10 fs are reported at the Linac Coherent Light Source (LCLS). Advanced time-resolved diagnostics approaching the fs-level have been proposed requiring the support of rf-deflectors, modern laser systems, or other complex systems. Though suffering from a loss of phase information, spectral diagnostics remain appealing by comparison as compact, low-cost systems suitable for deployment in beam dynamics studies and operations instrumentation. Progress in mid-IR imaging and detection of the corresponding micrometer-range power spectrum has led to the continuing development of a single-shot, 1.2 - 40 micrometer prism spectrometer for ultra-short bunch length monitoring. In this paper we report further analysis and experimental progress on the spectrometer installation at LCLS.

Paper

Title

Page

Ultra-short Electron Bunch and X-ray Temporal Diagnostics with an X-band Transverse Deflecting Cavity

441

P. Krejcik, Y. Ding, J.C. Frisch, Z. Huang, H. Loos, J.W. Wang, M.-H. Wang
SLAC, Menlo Park, California, USA
C. Behrens
DESY, Hamburg, Germany
P. Emma
LBNL, Berkeley, California, USA

Funding: This work was supported by Department of Energy Contract No. DE-AC0276SF00515
The technique of streaking an electron bunch with a RF deflecting cavity to measure its bunch length is being applied in a new way at the Linac Coherent Light Source with the goal of measuring the femtosecond temporal profile of the FEL photon beam. A powerful X-band deflecting cavity is being installed downstream of the FEL undulator and the streaked electron beam will be observed at an energy spectrometer screen at the beam dump. The single-shot measurements will reveal which time slices of the streaked beam have contributed to the FEL process by virtue of their greater energy loss and energy spread relative to the non-lasing portions of the electron bunch. Since the diagnostic is located downstream of the undulator it can be operated continuously without interrupting the beam to the users. The resolution of the new X-band system will be compared to the existing S-band RF deflecting diagnostic systems at SLAC and consideration is given to the required RF phase stability tolerances required for acceptable beam jitter on the monitor. Simulation studies show that about 1 fs (rms) time resolution is achievable in the LCLS over a wide range of FEL wavelengths and pulse lengths.

TUPA44

Status of the LCLS Experiment Timing System

453

J.C. Frisch, C. Bostedt, R.N. Coffee, A.R. Fry, N. Hartmann, J. May, D.J. Nicholson, S. Schorb, S.R. Smith
SLAC, Menlo Park, California, USA

Funding: Work Supported by Department of Energy Contract DE AC03 76SF00515
X-ray / optical laser pump - probe experiments are used for a significant fraction of the scientific work performed at LCLS. The experimental laser systems are locked to the timing of the electron beam through a combination of RF and optical fiber based systems. The remaining ~100 femtosecond RMS jitter of the X-rays relative to the optical laser is measured shot-to-shot by both a RF timing detector, and by direct X-ray to optical cross-correlation, and the result is used to correct the experiment timing to 10s of femtoseconds. We present the present status of the system and plans for future upgrades.

TUPA47

Middle-infrared Prism Spectrometer for Single-shot Bunch Length Diagnostics at the LCLS

463

T.J. Maxwell, Y. Ding, A.S. Fisher, J.C. Frisch, H. Loos
SLAC, Menlo Park, California, USA
C. Behrens
DESY, Hamburg, Germany

Funding: Work supported in part by US Department of Energy contract number DE-AC02-76SF00515.
Modern high-brightness accelerators such as laser plasma wakefield and free-electron lasers continue the drive to ever-shorter bunches. At low-charge (< 20 pC), bunches as short as 10 fs are reported at the Linac Coherent Light Source (LCLS). Advanced time-resolved diagnostics approaching the fs-level have been proposed requiring the support of rf-deflectors, modern laser systems, or other complex systems. Though suffering from a loss of phase information, spectral diagnostics remain appealing by comparison as compact, low-cost systems suitable for deployment in beam dynamics studies and operations instrumentation. Progress in mid-IR imaging and detection of the corresponding micrometer-range power spectrum has led to the continuing development of a single-shot, 1.2 - 40 micrometer prism spectrometer for ultra-short bunch length monitoring. In this paper we report further analysis and experimental progress on the spectrometer installation at LCLS.