Preble, J.
(Joe Preble)

THBOC04 Ampere Average Current Photoinjector and Energy Recovery Linac
Ilan Ben-Zvi, A. Burrill, R. Calaga, P. Cameron, X. Chang, D. Gassner, H. Hahn, A. Hershcovitch, H.C. Hseuh, P. Johnson, D. Kayran, J. Kewisch, R. Lambiase, Vladimir N. Litvinenko, G. McIntyre, A. Nicoletti, J. Rank, T. Roser, J. Scaduto, K. Smith, T. Srinivasan-Rao, K.-C. Wu, A. Zaltsman, Y. Zhao (BNL, Upton, Long Island, New York), H. Bluem, A. Burger, Mike Cole, A. Favale, D. Holmes, John Rathke, Tom Schultheiss, A. Todd (AES, Medford, NY), J. Delayen, W. Funk, L. Phillips, Joe Preble (Jefferson Lab, Newport News, Virginia)

High-power Free-Electron Lasers were made possible by advances in superconducting linac operated in an energy-recovery mode, as demonstrated by the spectacular success of the Jefferson Laboratory IR-Demo. In order to get to much higher power levels, say a fraction of a megawatt average power, many technological barriers are yet to be broken. BNL’s Collider-Accelerator Department is pursuing some of these technologies for a different application, that of electron cooling of high-energy hadron beams. I will describe work on CW, high-current and high-brightness electron beams. This will include a description of a superconducting, laser-photocathode RF gun employing a new secondary-emission multiplying cathode and an accelerator cavity, both capable of producing of the order of one ampere average current.

TUBOS02 Longitudinal Space Charge Effects in the JLAB IR FEL SRF Linac
Carlos Hernandez-Garcia, Kevin Beard, Chris Behre, Stephen Vincent Benson, George Herman Biallas, James Boyce, David Douglas, Fred Dylla, Richard Evans, Al Grippo, Joe Gubeli, David Hardy, Kevin Jordan, Lia Merminga, George Neil, Joe Preble, Michelle D. Shinn, Tim Siggins, Richard Walker, Gwyn Williams, Byung Yunn, Shukui Zhang (Jefferson Lab, Newport News, Virginia)

Observations of energy spread asymmetry when operating the Linac on either side of crest and longitudinal emittance growth have been confirmed by extending PARMELA simulations from the injector to the end of the first SRF Linac module. The asymmetry can be explained by the interaction of the accelerating electric field with that from longitudinal space charge effects within the electron bunch. This can be a major limitation to performance in FEL accelerators.

TUCOS02 High Power Lasing in the IR Upgrade FEL at Jefferson Lab
Stephen Vincent Benson, Kevin Beard, Chris Behre, George Herman Biallas, James Boyce, David Douglas, Fred Dylla, Richard Evans, Al Grippo, Joe Gubeli, David Hardy, Carlos Hernandez-Garcia, Kevin Jordan, Lia Merminga, George Neil, Joe Preble, Michelle D. Shinn, Tim Siggins, Richard Walker, Gwyn Williams, Byung Yunn, Shukui Zhang (Jefferson Lab, Newport News, Virginia), Hiroyuki Toyokawa (KEK, Ibaraki)

We report on progress in commissioning the IR Upgrade facility at Jefferson Lab. Operation at high power has been demonstrated at 5.7 microns with over 4 kW of continuous power output and a recirculated electron beam power of up to 800 kW. We report on the features and limitations of the present design and on efforts to increase the power to over 10 kW.

TUPOS64 High Current Energy Recovery Linac at BNL
Vladimir N. Litvinenko, Donald Barton, D. Beavis, Ilan Ben-Zvi, Michael Blaskiewicz, J.M. Brennan, A. Burrill, R. Calaga, P. Cameron, X. Chang, Roger Connolly, D. Gassner, H. Hahn, A. Hershcovitch, H.C. Hseuh, P. Johnson, D. Kayran, J. Kewisch, R. Lambiase, G. McIntyre, W. Meng, T. C. Nehring, A. Nicoletti, D. Pate, J. Rank, T. Roser, T. Russo, J. Scaduto, K. Smith, T. Srinivasan-Rao, N. Williams, K.-C. Wu, Vitaly Yakimenko, K. Yip, A. Zaltsman, Y. Zhao (BNL, Upton, Long Island, New York), H. Bluem, A. Burger, Mike Cole, A. Favale, D. Holmes, John Rathke, Tom Schultheiss, A. Todd (AES, Medford, NY), J. Delayen, W. Funk, L. Phillips, Joe Preble (Jefferson Lab, Newport News, Virginia)

We present the design, the parameters of a small test Energy Recovery Linac (ERL) facility, which is under construction at Collider-Accelerator Department, BNL. This R&D facility has goals to demonstrate CW operation of ERL with average beam current in the range of 0.1 - 1 ampere, combined with very high efficiency of energy recovery. A possibility for future up-grade to a two-pass ERL is considered. The heart of the facility is a 5-cell 700 MHz super-conducting RF linac with HOM damping. Flexible lattice of ERL provides a test-bed for testing issues of transverse and longitudinal instabilities and diagnostics of intense CW e-beam. ERL is also perfectly suited for a far-IR FEL. We present the status and our plans for construction and commissioning of this facility.