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Title: Longitudinal instability studies at the SURF II storage ring at NIST.

Abstract

Measurements of the longitudinal instability observed in the storage ring at the Synchrotrons Ultraviolet Radiation Facility (SURF II) at the National Institute of Standards and Technology (NET) were performed to understand the mechanism driving the instability. The instability, studied in depth by Ralcowsky and others, manifests itself in broad resonance features in the horizontal and vertical motion spectrum of the synchrotrons light from DC to a few kHz. Also observed are multiple synchrotrons harmonics that modulate the revolution harmonics; these are characteristic of longitudinal phase oscillations. These spectral features of the motion are found to be correlated with the periodic lengthening and shortening of the bunch length on time scales from {approximately}0.1 ms to 20 ms, depending on machine and radio-frequency (rf) system parameters. In this report, the growth rate of the instability is determined from measurements using an rf pickup electrode. The measured growth rates are compared to computed growth rates from an analytical model. Recommendations are made regarding options to control or mitigate the instability. In light of upgrade plans for SURF III, a few comments are presented about the beam lifetime.

Authors:
;
Publication Date:
Research Org.:
Argonne National Lab., IL (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
12093
Report Number(s):
LS-268
TRN: US0102355
DOE Contract Number:  
W-31109-ENG-38
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 27 Aug 1998
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; HARMONICS; INSTABILITY; PHASE OSCILLATIONS; RECOMMENDATIONS; SURF II STORAGE RING; ULTRAVIOLET RADIATION; BEAM BUNCHING; MITIGATION

Citation Formats

Harkay, K.C., and Sereno, N.S. Longitudinal instability studies at the SURF II storage ring at NIST.. United States: N. p., 1998. Web. doi:10.2172/12093.
Harkay, K.C., & Sereno, N.S. Longitudinal instability studies at the SURF II storage ring at NIST.. United States. doi:10.2172/12093.
Harkay, K.C., and Sereno, N.S. Thu . "Longitudinal instability studies at the SURF II storage ring at NIST.". United States. doi:10.2172/12093. https://www.osti.gov/servlets/purl/12093.
@article{osti_12093,
title = {Longitudinal instability studies at the SURF II storage ring at NIST.},
author = {Harkay, K.C. and Sereno, N.S.},
abstractNote = {Measurements of the longitudinal instability observed in the storage ring at the Synchrotrons Ultraviolet Radiation Facility (SURF II) at the National Institute of Standards and Technology (NET) were performed to understand the mechanism driving the instability. The instability, studied in depth by Ralcowsky and others, manifests itself in broad resonance features in the horizontal and vertical motion spectrum of the synchrotrons light from DC to a few kHz. Also observed are multiple synchrotrons harmonics that modulate the revolution harmonics; these are characteristic of longitudinal phase oscillations. These spectral features of the motion are found to be correlated with the periodic lengthening and shortening of the bunch length on time scales from {approximately}0.1 ms to 20 ms, depending on machine and radio-frequency (rf) system parameters. In this report, the growth rate of the instability is determined from measurements using an rf pickup electrode. The measured growth rates are compared to computed growth rates from an analytical model. Recommendations are made regarding options to control or mitigate the instability. In light of upgrade plans for SURF III, a few comments are presented about the beam lifetime.},
doi = {10.2172/12093},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1998},
month = {8}
}