4 papers

title:	Status and initial commissioning of a high gain 800 nm SASE FEL
format:	conference procceeding
conference:	21st International Free Electron Laser Conference
year:	2000
22 authors:	A. Tremaine | Pedro Frigola | A. Murokh | P. Musumeci | C. Pellegrini | J. B. Rosenzweig | M. Babzien | Ben-Zvi, I. | E. Johnson | R. Malone | G. Rakowsky | Skaritka, J. | X. J. Wang | Yu, L. H. | Van Bibber, K. A. | J. M. Hill | Le Sage, G. P. | R. Carr | M. Cornacchia | Nuhn, H. D. | Ruland, R. | D. C. Nguyen
abstract:	We describe the status and initial commissioning of the visible to infrared SASE amplifier (VISA) experiment. VISA uses a strong focusing 4 m undulator, the Brookhaven National Laboratory ATF linac with an energy of 72 MeV, and a photoinjector electron source. The VISA fundamental radiation wavelength is near 800 nm and the power expected at saturation is near 60 MW. Power, angular and spectral measurements are planned for the VISA radiation and these results will be analyzed and compared with SASE FEL theory and computer simulation. In addition, the induced electron beam micro-bunching will be measured using coherent transition radiation. (12 References).
keywords:
Download | View | Details | edit | delete

title:	Photon beam diagnostics for VISA FEL
format:	conference procceeding
conference:	1999 Particle Accelerator Conference
year:	1999
17 authors:	A. Murokh | C. Pellegrini | J. B. Rosenzweig | Pedro Frigola | P. Musumeci | A. Tremaine | M. Babzien | Ben-Zvi, I. | Doyuran, A. | E. Johnson | Skaritka, J. | X. J. Wang | Van Bibber, K. A. | J. M. Hill | Le Sage, G. P. | D. Nguyen | M. Cornacchia
abstract:	The VISA (Visible to Infrared SASE Amplifier) project is designed to be a SASE-FEL driven to saturation in the sub-micron wavelength region. Its goal is to test various aspects of the existing theory of self-amplified spontaneous emission, as well as numerical codes. Measurements include: angular and spectral distribution of the FEL light at the exit and inside of the undulator; electron beam micro-bunching using CTR; single-shot time resolved measurements of the pulse profile, using an auto-correlation technique and FROG algorithm. The diagnostics are designed to provide maximum information on the physics of the SASE-FEL process, to ensure a close comparison of the experimental results with theory and simulations. (9 References).
keywords:
Download | View | Details | edit | delete

title:	Synchronization of sub-picosecond electron and laser pulses
format:	conference procceeding
conference:	8th Advanced Accelerator Concepts Workshop
year:	1999
2 authors:	J. B. Rosenzweig | Le Sage, G. P.
abstract:	Pulse-compression techniques apply a longitudinal restoring force which improves synchronization between electron bunches and the RF drive, partially or completely correcting errors in the exit time from the injector. While this feature is beneficial in terms of linac related phase matching issues and jitter in the photocathode laser system, laser jitter with respect to the RF clock is in fact worsened in terms of the final interaction of laser and electron pulses. That is, if one attempts to synchronize the electron bunch to an external laser, deriving external laser timing from, say, the photocathode drive laser oscillator, the relative timing of electron and the external laser will be mismatched, because the electron beam is pulled toward a given phase of the RF clock. Thus, if one wishes to take advantage of the locking of the electron beam to the (assumed stable) RF clock, then an equivalent mechanism must be found for locking the external laser to the RF clock as well.
keywords:
Download | View | Details | edit | delete

title:	Time and frequency domain analysis of superradiant coherent synchrotron radiation in a waveguide free-electron laser
format:	unknown
year:	1994
6 authors:	A. Gover | F. V. Hartemann | Le Sage, G. P. | Luhmann, N. C., Jr. | R. S. Zhang | C. Pellegrini
abstract:	The coherent synchrotron radiation process in a waveguide is theoretically investigated. A single, short bunch propagating through a wiggler is considered. In a waveguide, two very distinct regimes are possible. At grazing, where the beam velocity matches the wave group velocity, the bunch emits a single, ultrashort chirped pulse whose duration is determined by the interaction bandwidth and the waveguide dispersion. Away from grazing, where slippage dominates, two distinct pulses are radiated at the Doppler upshifted and downshifted frequencies. Both the time and frequency domain expressions for the radiation characteristics are derived. (13 References).
keywords:
Download | View | Details | edit | delete