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Title: Relaxation Oscillations of the Synchrotron Motion Caused by Narrow-Band Impedances

Abstract

Although the linearized theory of small amplitude synchrotron oscillations and the instability thresholds derived from it have long been understood, there is no satisfactory description of the large amplitude highly non-linear synchrotron motion of a bunched beam. With an appropriate tuning of the RF cavity impedance, large amplitude, low frequency, self-sustained relaxation oscillations of this synchrotron motion are generated. This paper presents detailed experimental data of such behavior, tracking code results that reproduce the important characteristics, and a simple analytical model that explains the key features of the relaxation oscillation: growth of the instability, saturation of the oscillation, breakup of the bunch, and subsequent damping of the system back to the beginning of the next cycle of the relaxation oscillation.

Authors:
Publication Date:
Research Org.:
Stanford Linear Accelerator Center, Menlo Park, CA (US)
Sponsoring Org.:
USDOE Office of Energy Research (ER) (US)
OSTI Identifier:
15074
Report Number(s):
SLAC-PUB-8268
TRN: US0204532
DOE Contract Number:
AC03-76SF00515
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 4 Oct 1999
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; AMPLITUDES; DAMPING; ENERGY; IMPEDANCE; INSTABILITY; OSCILLATIONS; RELAXATION; SATURATION; SYNCHROTRON OSCILLATIONS; SYNCHROTRONS; TUNING

Citation Formats

Limborg, Cecile. Relaxation Oscillations of the Synchrotron Motion Caused by Narrow-Band Impedances. United States: N. p., 1999. Web. doi:10.2172/15074.
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Limborg, Cecile. Relaxation Oscillations of the Synchrotron Motion Caused by Narrow-Band Impedances. United States. doi:10.2172/15074.
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Limborg, Cecile. Mon . "Relaxation Oscillations of the Synchrotron Motion Caused by Narrow-Band Impedances". United States. doi:10.2172/15074. https://www.osti.gov/servlets/purl/15074.
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@article{osti_15074,
title = {Relaxation Oscillations of the Synchrotron Motion Caused by Narrow-Band Impedances},
author = {Limborg, Cecile},
abstractNote = {Although the linearized theory of small amplitude synchrotron oscillations and the instability thresholds derived from it have long been understood, there is no satisfactory description of the large amplitude highly non-linear synchrotron motion of a bunched beam. With an appropriate tuning of the RF cavity impedance, large amplitude, low frequency, self-sustained relaxation oscillations of this synchrotron motion are generated. This paper presents detailed experimental data of such behavior, tracking code results that reproduce the important characteristics, and a simple analytical model that explains the key features of the relaxation oscillation: growth of the instability, saturation of the oscillation, breakup of the bunch, and subsequent damping of the system back to the beginning of the next cycle of the relaxation oscillation.},
doi = {10.2172/15074},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Oct 04 00:00:00 EDT 1999},
month = {Mon Oct 04 00:00:00 EDT 1999}
}
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DOI:  10.2172/15074
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