IPAC2011 - List of Authors (Jongewaard, E.N.)

Paper	Title	Page
MOPC067	X-Band Test Station at Lawrence Livermore National Laboratory	235
	R.A. Marsh, F. Albert, S.G. Anderson, C.P.J. Barty, G.K. Beer, R.R. Cross, G.A. Deis, C.A. Ebbers, D.J. Gibson, F.V. Hartemann, T.L. Houck LLNL, Livermore, California, USA C. Adolphsen, A.E. Candel, T.S. Chu, E.N. Jongewaard, Z. Li, C. Limborg-Deprey, T.O. Raubenheimer, S.G. Tantawi, A.E. Vlieks, F. Wang, J.W. Wang, F. Zhou SLAC, Menlo Park, California, USA
	Funding: This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. An X-band multi-bunch test station is being built at LLNL to investigate the science and technology paths required to boost the current mono-energetic gamma-ray (MEGa-Ray) brightness by orders of magnitude. The test station will consist of a 5.5 cell X-band RF photoinjector, single accelerator section, and beam diagnostics. Beam quality must be exceedingly high in order to produce narrow-bandwidth gamma-rays, requiring a robust state of the art photoinjector. The photoinjector will be a high gradient (200 MV/m peak surface field on the cathode) standing wave structure, featuring a dual feed racetrack coupler, elliptical irises, and an optimized first cell length. A solid-state Scandinova modulator will power a single SLAC XL4 11.424 GHz 50 MW klystron. RF distribution will allow for full powering of the photoinjector with the balance of the RF powering a single accelerator section so that the electron parameters can be measured. The status of the facility will be presented including commissioning schedule and first experiment plans. Future experimental programs pertinent to Compton scattering R&D, high gradient structure testing, and light source development will be discussed.

MOPC142	25 Year Performance Review of the SLAC 5045 S-Band Klystron	409
	A. Jensen, A.S. Beebe, M.V. Fazio, A.A. Haase, E.N. Jongewaard, C. Pearson, D.W. Sprehn, A.E. Vlieks, L.E. Whicker SLAC, Menlo Park, California, USA
	Funding: This work was supported by the U.S. Department of Energy under contract DE-AC03-76SF00515. The SLAC 5045 S-band klystron has proven to be a remarkably reliable high peak power tube. Originally developed in the 1980’s as an upgraded RF power source for the Stanford Linear Collider, it has continually powered the SLAC linac in support of numerous programs in particle physics and photon science. The large number of tubes built and operated (more than 800) coupled with accumulated running statistics over the last 25+ years represents an unprecedented wealth of operational experience for high pulse power klystrons in accelerator applications. Mean time between failures has continued to rise during this period and is frequently in excess of 100,000 hours during the last several years. Lifetime statistics as well as some important failure modes are presented and examined here.

MOPC143	A Reduced Gradient Output Design for SLAC's XL4 X-Band Klystron	412
	A. Jensen, C. Adolphsen, A.E. Candel, M.V. Fazio, E.N. Jongewaard, D.W. Sprehn, A.E. Vlieks, F. Wang SLAC, Menlo Park, California, USA
	Funding: This work was supported by the U.S. Department of Energy under contract DE-AC03-76SF00515. X-band klystron work began at SLAC in the mid to late 1980's to develop high frequency (4 times the SLAC S-band klystron), high power RF sources for the linear collider designs under consideration at that time. This work culminated in the current workhorse X-band RF source, the XL4. To date 26 XL4 tubes have been built. The XL4 4-cell disk loaded traveling wave output structure has a high operating gradient. A new 6-cell structure has been designed to reduce breakdown and to further improve the klystron's robustness. Initial simulations show the 6-cell design reduces the gradient roughly 25% and that the structure is stable. A physical XL4 will be retrofitted with the new output cavity and hot tested in the near future.

TUPO024	Precision X-band Linac Technologies for Nuclear Photonics Gamma-ray Sources	1491
	F.V. Hartemann, F. Albert, S.G. Anderson, C.P.J. Barty, A.J. Bayramian, R.R. Cross, G.A. Deis, C.A. Ebbers, D.J. Gibson, T.L. Houck, R.A. Marsh, M. J. Messerly, S.S.Q. Wu LLNL, Livermore, California, USA C. Adolphsen, A.E. Candel, T.S. Chu, M.V. Fazio, E.N. Jongewaard, Z. Li, C. Limborg-Deprey, T.O. Raubenheimer, S.G. Tantawi, A.E. Vlieks, F. Wang, J.W. Wang, F. Zhou SLAC, Menlo Park, California, USA D. Cutoiu Horia Hulubei National Institute for Physics and Nuclear Engineering, Bucharest, Romania D. Ighigeanu, M. Toma INFLPR, Bucharest - Magurele, Romania V.A. Semenov UCB, Berkeley, California, USA
	Funding: This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Nuclear photonics is an emerging field of research requiring new tools, including high spectral brightness, tunable gamma-ray sources; high photon energy, ultrahigh-resolution crystal spectrometers; and novel detectors. This presentation focuses on the precision linac technology required for Compton scattering gamma-ray light sources, and on the optimization of the laser and electron beam pulse format to achieve unprecedented spectral brightness. Within this context, high-gradient X-band technology will be shown to offer optimal performance in a compact package, when used in conjunction with the appropriate pulse format, and photocathode illumination and interaction laser technologies.

Paper

Title

Page

X-Band Test Station at Lawrence Livermore National Laboratory

235

R.A. Marsh, F. Albert, S.G. Anderson, C.P.J. Barty, G.K. Beer, R.R. Cross, G.A. Deis, C.A. Ebbers, D.J. Gibson, F.V. Hartemann, T.L. Houck
LLNL, Livermore, California, USA
C. Adolphsen, A.E. Candel, T.S. Chu, E.N. Jongewaard, Z. Li, C. Limborg-Deprey, T.O. Raubenheimer, S.G. Tantawi, A.E. Vlieks, F. Wang, J.W. Wang, F. Zhou
SLAC, Menlo Park, California, USA

Funding: This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
An X-band multi-bunch test station is being built at LLNL to investigate the science and technology paths required to boost the current mono-energetic gamma-ray (MEGa-Ray) brightness by orders of magnitude. The test station will consist of a 5.5 cell X-band RF photoinjector, single accelerator section, and beam diagnostics. Beam quality must be exceedingly high in order to produce narrow-bandwidth gamma-rays, requiring a robust state of the art photoinjector. The photoinjector will be a high gradient (200 MV/m peak surface field on the cathode) standing wave structure, featuring a dual feed racetrack coupler, elliptical irises, and an optimized first cell length. A solid-state Scandinova modulator will power a single SLAC XL4 11.424 GHz 50 MW klystron. RF distribution will allow for full powering of the photoinjector with the balance of the RF powering a single accelerator section so that the electron parameters can be measured. The status of the facility will be presented including commissioning schedule and first experiment plans. Future experimental programs pertinent to Compton scattering R&D, high gradient structure testing, and light source development will be discussed.

MOPC142

25 Year Performance Review of the SLAC 5045 S-Band Klystron

409

A. Jensen, A.S. Beebe, M.V. Fazio, A.A. Haase, E.N. Jongewaard, C. Pearson, D.W. Sprehn, A.E. Vlieks, L.E. Whicker
SLAC, Menlo Park, California, USA

Funding: This work was supported by the U.S. Department of Energy under contract DE-AC03-76SF00515.
The SLAC 5045 S-band klystron has proven to be a remarkably reliable high peak power tube. Originally developed in the 1980’s as an upgraded RF power source for the Stanford Linear Collider, it has continually powered the SLAC linac in support of numerous programs in particle physics and photon science. The large number of tubes built and operated (more than 800) coupled with accumulated running statistics over the last 25+ years represents an unprecedented wealth of operational experience for high pulse power klystrons in accelerator applications. Mean time between failures has continued to rise during this period and is frequently in excess of 100,000 hours during the last several years. Lifetime statistics as well as some important failure modes are presented and examined here.

MOPC143

A Reduced Gradient Output Design for SLAC's XL4 X-Band Klystron

412

A. Jensen, C. Adolphsen, A.E. Candel, M.V. Fazio, E.N. Jongewaard, D.W. Sprehn, A.E. Vlieks, F. Wang
SLAC, Menlo Park, California, USA

Funding: This work was supported by the U.S. Department of Energy under contract DE-AC03-76SF00515.
X-band klystron work began at SLAC in the mid to late 1980's to develop high frequency (4 times the SLAC S-band klystron), high power RF sources for the linear collider designs under consideration at that time. This work culminated in the current workhorse X-band RF source, the XL4. To date 26 XL4 tubes have been built. The XL4 4-cell disk loaded traveling wave output structure has a high operating gradient. A new 6-cell structure has been designed to reduce breakdown and to further improve the klystron's robustness. Initial simulations show the 6-cell design reduces the gradient roughly 25% and that the structure is stable. A physical XL4 will be retrofitted with the new output cavity and hot tested in the near future.

TUPO024

Precision X-band Linac Technologies for Nuclear Photonics Gamma-ray Sources

1491

F.V. Hartemann, F. Albert, S.G. Anderson, C.P.J. Barty, A.J. Bayramian, R.R. Cross, G.A. Deis, C.A. Ebbers, D.J. Gibson, T.L. Houck, R.A. Marsh, M. J. Messerly, S.S.Q. Wu
LLNL, Livermore, California, USA
C. Adolphsen, A.E. Candel, T.S. Chu, M.V. Fazio, E.N. Jongewaard, Z. Li, C. Limborg-Deprey, T.O. Raubenheimer, S.G. Tantawi, A.E. Vlieks, F. Wang, J.W. Wang, F. Zhou
SLAC, Menlo Park, California, USA
D. Cutoiu
Horia Hulubei National Institute for Physics and Nuclear Engineering, Bucharest, Romania
D. Ighigeanu, M. Toma
INFLPR, Bucharest - Magurele, Romania
V.A. Semenov
UCB, Berkeley, California, USA

Funding: This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
Nuclear photonics is an emerging field of research requiring new tools, including high spectral brightness, tunable gamma-ray sources; high photon energy, ultrahigh-resolution crystal spectrometers; and novel detectors. This presentation focuses on the precision linac technology required for Compton scattering gamma-ray light sources, and on the optimization of the laser and electron beam pulse format to achieve unprecedented spectral brightness. Within this context, high-gradient X-band technology will be shown to offer optimal performance in a compact package, when used in conjunction with the appropriate pulse format, and photocathode illumination and interaction laser technologies.