IPAC2016 - List of Authors (Vrielink, A.R.)

Paper	Title	Page
MOPMY034	The Distributed Bunch Amplifier	573
	M.A. Franzi, A. Jensen, S.G. Tantawi, F. Toufexis, A.R. Vrielink SLAC, Menlo Park, California, USA
	The Distributed Bunch Amplifier (DBA) is a high efficiency RF source that utilizes a phase locked deflecting cavity and output circuit to produce a synchronous beam-wave interaction. The DBA improves on the design of previous embodiments of this technology, such as the Gyrocon, by implementing a modern decoupled output circuit design and conical PPM beam focusing array in order to scale to higher frequencies and efficiency than previously demonstrated. Presented is a proof-of-concept S-band, 2.856 GHz, device operating with a 60 kV, 8 Amp, electron beam. Each stage of the three-cavity decoupled output circuit is optimized based on complex amplitude and shunt impedance to achieve an electronic efficiency of greater than 90%. Initial numerical analysis of this design indicates that an overall operating efficiency of greater than 70% is feasible. Detailed simulated results of the S-band model and designs to scale this technology to higher power and frequency will be discussed. Budker, G. I., et al. "The Gyrocon: An Efficient Relativistic High Power VHF Generator." Part. Accel. 10 (1979): 41-59.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY034
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MOPMY035	Theoretical Analysis and Simulation of a Compact Frequency Multiplier for High Power Millimeter and Terahertz Sources	576
SUPSS098	use link to see paper's listing under its alternate paper code
	A.R. Vrielink, S.G. Tantawi, F. Toufexis SLAC, Menlo Park, California, USA
	As the demands on accelerating gradients and the temporal resolution of beam diagnostics and manipulation schemes grow, millimeter-wave and terahertz (THz) accelerator structures may present a natural solution. The recent advent of a radiofrequency undulator and the development of a 0.45 THz accelerator demonstrate growing interest in this frequency regime; however, growth in this area is limited by the lack of efficient, compact high power sources. We present a novel vacuum electronic device featuring an interaction between a radially bunched electron beam and azimuthally traveling waves. The use of an inward traveling radial sheet beam mitigates space charge effects at the low operating energy of 10-30 keV and allows for a high input beam current of approximately 0.5-10 A. Based on preliminary calculations, these devices could operate from 50 GHz to 250 GHz with tens of kiloWatts of output power, while the expected efficiency would scale from 60% at 80 GHz to 15% at 230 GHz. Here we present the underlying theory, possible structure design, and preliminary results from analytical calculations and simulation. Tantawi, S. et al. Phys. Rev. Lett. 112, 164802 (April, 2014) Nanni, E. et al. Nat. Commun. 6, 8486 (October, 2015)
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY035
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MOPMY036	High-harmonic mm-Wave Frequency Multiplication using a Gyrocon-like Device	579
	F. Toufexis, V.A. Dolgashev, M.V. Fazio, A. Jensen, S.G. Tantawi, A.R. Vrielink SLAC, Menlo Park, California, USA P. Borchard Dymenso LLC, San Francisco, USA
	Funding: This project was funded by U.S. Department of Energy under Contract No. DE-AC02-76SF00515, and the National Science Foundation. Traditional linear interaction RF sources, such as Klystrons and Traveling Wave Tubes, fail to produce significant power levels at millimeter wavelengths. This is because their critical dimensions are small compared to the wavelength, and the output power scales as the square of the wavelength. We present a vacuum tube technology, where the device size is inherently larger than the operating wavelength. We designed a low–voltage mm–wave source, with an output interaction circuit based on a spherical sector cavity. This device was configured as a phased-locked frequency multiplier. We report the design and cold test results of a proof-of-principle fifth harmonic frequency multiplier with an output frequency of 57.12 GHz.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY036
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FRXBB01	Achieved Performance of an All X-band Photo-injector	4253
	C. Limborg, C. Adolphsen, M.P. Dunning, R.K. Jobe, H. Li, D.J. McCormick, T.O. Raubenheimer, T. Vecchione, A.R. Vrielink, F.Y. Wang, S.P. Weathersby SLAC, Menlo Park, California, USA
	Funding: Work funded by DOE/SU Contract DE-AC02-76-SF00515 Building more compact accelerators to deliver high brightness electron beams for the generation of high flux, highly coherent radiation is a priority for the photon science community. A relatively straightforward reduction in footprint can be achieved by using high-gradient X-Band (11.4 GHz) RF technology. This talk presents the all X-band photo-injector facility at SLAC, covering the benefits of using this technology and highlighting the performance achieved.
	Slides FRXBB01 [40.418 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-FRXBB01
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Paper

Title

Page

The Distributed Bunch Amplifier

573

M.A. Franzi, A. Jensen, S.G. Tantawi, F. Toufexis, A.R. Vrielink
SLAC, Menlo Park, California, USA

The Distributed Bunch Amplifier (DBA) is a high efficiency RF source that utilizes a phase locked deflecting cavity and output circuit to produce a synchronous beam-wave interaction. The DBA improves on the design of previous embodiments of this technology, such as the Gyrocon*, by implementing a modern decoupled output circuit design and conical PPM beam focusing array in order to scale to higher frequencies and efficiency than previously demonstrated. Presented is a proof-of-concept S-band, 2.856 GHz, device operating with a 60 kV, 8 Amp, electron beam. Each stage of the three-cavity decoupled output circuit is optimized based on complex amplitude and shunt impedance to achieve an electronic efficiency of greater than 90%. Initial numerical analysis of this design indicates that an overall operating efficiency of greater than 70% is feasible. Detailed simulated results of the S-band model and designs to scale this technology to higher power and frequency will be discussed.
* Budker, G. I., et al. "The Gyrocon: An Efficient Relativistic High Power VHF Generator." Part. Accel. 10 (1979): 41-59.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY034

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMY035

Theoretical Analysis and Simulation of a Compact Frequency Multiplier for High Power Millimeter and Terahertz Sources

576

SUPSS098

use link to see paper's listing under its alternate paper code

A.R. Vrielink, S.G. Tantawi, F. Toufexis
SLAC, Menlo Park, California, USA

As the demands on accelerating gradients and the temporal resolution of beam diagnostics and manipulation schemes grow, millimeter-wave and terahertz (THz) accelerator structures may present a natural solution. The recent advent of a radiofrequency undulator and the development of a 0.45 THz accelerator demonstrate growing interest in this frequency regime; however, growth in this area is limited by the lack of efficient, compact high power sources. We present a novel vacuum electronic device featuring an interaction between a radially bunched electron beam and azimuthally traveling waves. The use of an inward traveling radial sheet beam mitigates space charge effects at the low operating energy of 10-30 keV and allows for a high input beam current of approximately 0.5-10 A. Based on preliminary calculations, these devices could operate from 50 GHz to 250 GHz with tens of kiloWatts of output power, while the expected efficiency would scale from 60% at 80 GHz to 15% at 230 GHz. Here we present the underlying theory, possible structure design, and preliminary results from analytical calculations and simulation.
Tantawi, S. et al. Phys. Rev. Lett. 112, 164802 (April, 2014)
Nanni, E. et al. Nat. Commun. 6, 8486 (October, 2015)

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY035

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MOPMY036

High-harmonic mm-Wave Frequency Multiplication using a Gyrocon-like Device

579

F. Toufexis, V.A. Dolgashev, M.V. Fazio, A. Jensen, S.G. Tantawi, A.R. Vrielink
SLAC, Menlo Park, California, USA
P. Borchard
Dymenso LLC, San Francisco, USA

Funding: This project was funded by U.S. Department of Energy under Contract No. DE-AC02-76SF00515, and the National Science Foundation.
Traditional linear interaction RF sources, such as Klystrons and Traveling Wave Tubes, fail to produce significant power levels at millimeter wavelengths. This is because their critical dimensions are small compared to the wavelength, and the output power scales as the square of the wavelength. We present a vacuum tube technology, where the device size is inherently larger than the operating wavelength. We designed a low–voltage mm–wave source, with an output interaction circuit based on a spherical sector cavity. This device was configured as a phased-locked frequency multiplier. We report the design and cold test results of a proof-of-principle fifth harmonic frequency multiplier with an output frequency of 57.12 GHz.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY036

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRXBB01

Achieved Performance of an All X-band Photo-injector

4253

C. Limborg, C. Adolphsen, M.P. Dunning, R.K. Jobe, H. Li, D.J. McCormick, T.O. Raubenheimer, T. Vecchione, A.R. Vrielink, F.Y. Wang, S.P. Weathersby
SLAC, Menlo Park, California, USA

Funding: Work funded by DOE/SU Contract DE-AC02-76-SF00515
Building more compact accelerators to deliver high brightness electron beams for the generation of high flux, highly coherent radiation is a priority for the photon science community. A relatively straightforward reduction in footprint can be achieved by using high-gradient X-Band (11.4 GHz) RF technology. This talk presents the all X-band photo-injector facility at SLAC, covering the benefits of using this technology and highlighting the performance achieved.

Slides FRXBB01 [40.418 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-FRXBB01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)