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Title: IMPEDANCE AND INSTABILITIES IN THE NLC DAMPING RINGS

Abstract

We report on impedance calculations and single-bunch and multi-bunch instabilities in the NLC damping rings. Preliminary designs of vacuum chambers and major components have addressed beam impedance issues, with the desire to increase instability current thresholds and reducing growth rates. MAFIA calculations of short-range and long-range wakefields have allowed computations of growth rates and thresholds, which are presented here. Resistive wall instability dominates long-range effects, and requires a broadband feedback system to control coupled-bunch motion. Growth rates are within the range addressable by current feedback system technologies. Single-bunch instability thresholds are safely above nominal operating current.

Authors:
Publication Date:
Research Org.:
Stanford Linear Accelerator Center, Menlo Park, CA (US)
Sponsoring Org.:
USDOE Office of Energy Research (ER) (US)
OSTI Identifier:
800042
Report Number(s):
SLAC-PUB-9424
TRN: US200308%%388
DOE Contract Number:
AC03-76SF00515
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 20 Aug 2002
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; LINEAR COLLIDERS; DAMPING; FEEDBACK; IMPEDANCE; INSTABILITY; BEAM BUNCHING

Citation Formats

Novokhatski, Alexander. IMPEDANCE AND INSTABILITIES IN THE NLC DAMPING RINGS. United States: N. p., 2002. Web. doi:10.2172/800042.
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Novokhatski, Alexander. IMPEDANCE AND INSTABILITIES IN THE NLC DAMPING RINGS. United States. doi:10.2172/800042.
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Novokhatski, Alexander. Tue . "IMPEDANCE AND INSTABILITIES IN THE NLC DAMPING RINGS". United States. doi:10.2172/800042. https://www.osti.gov/servlets/purl/800042.
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@article{osti_800042,
title = {IMPEDANCE AND INSTABILITIES IN THE NLC DAMPING RINGS},
author = {Novokhatski, Alexander},
abstractNote = {We report on impedance calculations and single-bunch and multi-bunch instabilities in the NLC damping rings. Preliminary designs of vacuum chambers and major components have addressed beam impedance issues, with the desire to increase instability current thresholds and reducing growth rates. MAFIA calculations of short-range and long-range wakefields have allowed computations of growth rates and thresholds, which are presented here. Resistive wall instability dominates long-range effects, and requires a broadband feedback system to control coupled-bunch motion. Growth rates are within the range addressable by current feedback system technologies. Single-bunch instability thresholds are safely above nominal operating current.},
doi = {10.2172/800042},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 20 00:00:00 EDT 2002},
month = {Tue Aug 20 00:00:00 EDT 2002}
}
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DOI:  10.2172/800042
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  • ; ; ; ...
    We report on impedance calculations and single-bunch and multi-bunch instabilities in the NLC damping rings. Preliminary designs of vacuum chambers and major components have addressed beam impedance issues, with the desire to increase instability current thresholds and reducing growth rates. MAFIA calculations of short-range and long-range wakefields have allowed computations of growth rates and thresholds, which are presented here. Resistive wall instability dominates long-range effects, and requires a broadband feedback system to control coupled-bunch motion. Growth rates are within the range addressable by current feedback system technologies. Single-bunch instability thresholds are safely above nominal operating current.

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