LINAC2014 - List of Keywords (network)

Paper	Title	Other Keywords	Page
MOPP055	RF Tests of Dressed 325 MHz Single-Spoke Resonators at 2 K	cavity, operation, LLRF, resonance	180
	A. Hocker, E. Cullerton, B.M. Hanna, W. Schappert, A.I. Sukhanov Fermilab, Batavia, Illinois, USA
	Funding: United States Department of Energy, Contract No.DE- AC02-07CH11359 Fermilab has recently completed an upgrade to its spoke resonator test cryostat to enable testing of cavities in superfluid helium. Two single-spoke resonators with differing helium vessel designs have been tested in this new configuration. Gradient and Q0 performance was studied along with microphonics control and sensitivity of the resonant frequency to pressure variations. A description of the testing and the results obtained are presented.
	Poster MOPP055 [0.437 MB]

THPP023	Affordable Short Pulse Marx Modulator	high-voltage, controls, flattop, linear-collider	886
	R.A. Phillips, G. DelPriore, M.P.J. Gaudreau, M.K. Kempkes Diversified Technologies, Inc., Bedford, Massachusetts, USA J.A. Casey Rockfield Research Inc., Las Vegas, Nevada, USA
	High energy, short-pulse modulators are being re-examined for the Compact Linear Collider (CLIC) and numerous X-Band accelerator designs. At the very high voltages required for these systems, all of the existing designs are based on pulse transformers, which significantly limit their performance and efficiency. There is not a fully optimized, transformer-less modulator design capable of meeting the demanding requirements of very high voltage pulses at short pulse widths. Under a U.S. Department of Energy grant, Diversified Technologies, Inc. (DTI) is developing a short pulse, solid-state Marx modulator. The modulator is designed for high efficiency in the 100 kV to 500 kV range, for currents up to 250 A, pulse lengths of 0.2 to 5.0 μs, and risetimes <300 ns. Key objectives of the development effort are modularity and scalability, combined with low cost and ease of manufacture. For short-pulse modulators, this Marx topology provides a means to achieve fast risetimes and flattop control that are not available with hard switch or transformer-coupled topologies. The system is in the final stages of testing prior to installation at Yale University.

THPP140	High Transparent Matched Window for Standing Wave Linear Accelerators	linac, electron, vacuum, coupling	1192
	A. Leggieri, F. Di Paolo, D. Passi Università degli Studi di Roma "Tor Vergata", Roma, Italy A. Ciccotelli, G. Felici S.I.T., Aprilia, Italy
	This paper proposes a particular Dielectric Window (DW) for Standing Wave (SW) Linear Accelerators (LINAC’s). This study investigates the in-frequency return loss behavior of the LINAC, in order to improve matching and transmitting conditions while maintaining the optimum coupling between LINAC and High Power Microwave (HPMW) source. Device design is single-frequency based and considers the DW interface as an Input Matching Network (IMN) at the LINAC Normal Mode (NM) working frequency. Thus, design formulas are provided and Computer Aided Design (CAD) techniques are proposed. A prototype has been made and tested by performing cold S-parameter and Percentage Depth Dose (PDD) measurements of a LINAC with the proposed DW and with a traditional DW. The proposed device offers more energy transport attitude over the traditional DW, as shown by a return loss increase of 167% and an output electron energy increase of 5.5% while maintaining the same LINAC input power settings. This solution can offer a decrease of power line size, weight and cost. An after brazing global improvement of the accelerator figures of merit is also possible, as this study have demonstrated. [1]Hiroyuki Arai, 1986 [2]K. Hirano, 1995 [3]Y. Otake, 1995 [5]A. Leggieri, 2014 [6]A. C. Ugural, 2003 [7]A. Leggieri, 2014 [8]F. Di Paolo, 2000 [9]N. Marcuvitz, 1951

Paper

Title

Other Keywords

Page

MOPP055

RF Tests of Dressed 325 MHz Single-Spoke Resonators at 2 K

cavity, operation, LLRF, resonance

180

A. Hocker, E. Cullerton, B.M. Hanna, W. Schappert, A.I. Sukhanov
Fermilab, Batavia, Illinois, USA

Funding: United States Department of Energy, Contract No.DE- AC02-07CH11359
Fermilab has recently completed an upgrade to its spoke resonator test cryostat to enable testing of cavities in superfluid helium. Two single-spoke resonators with differing helium vessel designs have been tested in this new configuration. Gradient and Q0 performance was studied along with microphonics control and sensitivity of the resonant frequency to pressure variations. A description of the testing and the results obtained are presented.

Poster MOPP055 [0.437 MB]

THPP023

Affordable Short Pulse Marx Modulator

high-voltage, controls, flattop, linear-collider

886

R.A. Phillips, G. DelPriore, M.P.J. Gaudreau, M.K. Kempkes
Diversified Technologies, Inc., Bedford, Massachusetts, USA
J.A. Casey
Rockfield Research Inc., Las Vegas, Nevada, USA

High energy, short-pulse modulators are being re-examined for the Compact Linear Collider (CLIC) and numerous X-Band accelerator designs. At the very high voltages required for these systems, all of the existing designs are based on pulse transformers, which significantly limit their performance and efficiency. There is not a fully optimized, transformer-less modulator design capable of meeting the demanding requirements of very high voltage pulses at short pulse widths. Under a U.S. Department of Energy grant, Diversified Technologies, Inc. (DTI) is developing a short pulse, solid-state Marx modulator. The modulator is designed for high efficiency in the 100 kV to 500 kV range, for currents up to 250 A, pulse lengths of 0.2 to 5.0 μs, and risetimes <300 ns. Key objectives of the development effort are modularity and scalability, combined with low cost and ease of manufacture. For short-pulse modulators, this Marx topology provides a means to achieve fast risetimes and flattop control that are not available with hard switch or transformer-coupled topologies. The system is in the final stages of testing prior to installation at Yale University.

THPP140

High Transparent Matched Window for Standing Wave Linear Accelerators

linac, electron, vacuum, coupling

1192

A. Leggieri, F. Di Paolo, D. Passi
Università degli Studi di Roma "Tor Vergata", Roma, Italy
A. Ciccotelli, G. Felici
S.I.T., Aprilia, Italy

This paper proposes a particular Dielectric Window (DW) for Standing Wave (SW) Linear Accelerators (LINAC’s). This study investigates the in-frequency return loss behavior of the LINAC, in order to improve matching and transmitting conditions while maintaining the optimum coupling between LINAC and High Power Microwave (HPMW) source. Device design is single-frequency based and considers the DW interface as an Input Matching Network (IMN) at the LINAC Normal Mode (NM) working frequency. Thus, design formulas are provided and Computer Aided Design (CAD) techniques are proposed. A prototype has been made and tested by performing cold S-parameter and Percentage Depth Dose (PDD) measurements of a LINAC with the proposed DW and with a traditional DW. The proposed device offers more energy transport attitude over the traditional DW, as shown by a return loss increase of 167% and an output electron energy increase of 5.5% while maintaining the same LINAC input power settings. This solution can offer a decrease of power line size, weight and cost. An after brazing global improvement of the accelerator figures of merit is also possible, as this study have demonstrated.
[1]Hiroyuki Arai, 1986
[2]K. Hirano, 1995
[3]Y. Otake, 1995
[5]A. Leggieri, 2014
[6]A. C. Ugural, 2003
[7]A. Leggieri, 2014
[8]F. Di Paolo, 2000
[9]N. Marcuvitz, 1951