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Title: Determination of Field Amplitude and Synchronous Phase Using the Beam-Induced Signal in an Unpowered Superconducting Cavity

Abstract

At the Spallation Neutron Source superconducting linear accelerator, RF fields excited by a pulsed, high-intensity drifting beam in an unpowered superconducting cavity are measured with the cavity control circuit, in order to determine the synchronous phase and to calibrate the pickup probe of the cavity. Measurement errors arising from noise and from the excitation of other pass-band modes in the cavity are analyzed. The phase change due to beam acceleration as well as due to cavity detuning is computed with a model which is described in this paper. Simulation results show excellent agreement with measurements performed in drifting beam experiments. The measured cavity synchronous phase and accelerating gradient determined from the drifting beam measurements are in good agreement with those obtained from a time-of-flight based technique.

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931442
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment; Journal Volume: 571; Journal Issue: 3
Country of Publication:
United States
Language:
English

Citation Formats

Zhang, Yan, Campisi, Isidoro E, Chu, Paul C, Galambos, John D, and Henderson, Stuart D. Determination of Field Amplitude and Synchronous Phase Using the Beam-Induced Signal in an Unpowered Superconducting Cavity. United States: N. p., 2007. Web. doi:10.1016/j.nima.2006.10.397.
Zhang, Yan, Campisi, Isidoro E, Chu, Paul C, Galambos, John D, & Henderson, Stuart D. Determination of Field Amplitude and Synchronous Phase Using the Beam-Induced Signal in an Unpowered Superconducting Cavity. United States. doi:10.1016/j.nima.2006.10.397.
Zhang, Yan, Campisi, Isidoro E, Chu, Paul C, Galambos, John D, and Henderson, Stuart D. Mon . "Determination of Field Amplitude and Synchronous Phase Using the Beam-Induced Signal in an Unpowered Superconducting Cavity". United States. doi:10.1016/j.nima.2006.10.397.
@article{osti_931442,
title = {Determination of Field Amplitude and Synchronous Phase Using the Beam-Induced Signal in an Unpowered Superconducting Cavity},
author = {Zhang, Yan and Campisi, Isidoro E and Chu, Paul C and Galambos, John D and Henderson, Stuart D},
abstractNote = {At the Spallation Neutron Source superconducting linear accelerator, RF fields excited by a pulsed, high-intensity drifting beam in an unpowered superconducting cavity are measured with the cavity control circuit, in order to determine the synchronous phase and to calibrate the pickup probe of the cavity. Measurement errors arising from noise and from the excitation of other pass-band modes in the cavity are analyzed. The phase change due to beam acceleration as well as due to cavity detuning is computed with a model which is described in this paper. Simulation results show excellent agreement with measurements performed in drifting beam experiments. The measured cavity synchronous phase and accelerating gradient determined from the drifting beam measurements are in good agreement with those obtained from a time-of-flight based technique.},
doi = {10.1016/j.nima.2006.10.397},
journal = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment},
number = 3,
volume = 571,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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