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Title: Modeling and Simulation of Longitudinal Dynamics for LER-HER PEP II Rings

Abstract

A time domain modeling and simulation tool for beam-cavity interactions in LER and HER rings at PEP II are presented. The motivation for this tool is to explore the stability margins and performance limits of PEP II RF systems at higher currents and upgraded RF configurations. It also serves as test bed for new control algorithms and can define the ultimate limits of the architecture. The time domain program captures the dynamical behavior of the beam-cavity interaction based on a reduced model. The ring current is represented by macro-bunches. Multiple RF station in the ring are represented via one or two macro-cavities. Each macro-cavity captures the overall behavior of all the 2 or 4 cavity RF station. Station models include nonlinear elements in the klystron and signal processing. This allows modeling the principal longitudinal impedance control loops interacting with the longitudinal beam model. Validation of simulation tool is in progress by comparing the measured growth rates for both LER and HER rings with simulation results. The simulated behavior of both machines at high currents are presented comparing different control strategies and the effect of non-linear klystrons in the growth rates.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
900593
Report Number(s):
SLAC-PUB-12375
TRN: US0702341
DOE Contract Number:
AC02-76SF00515
Resource Type:
Conference
Resource Relation:
Conference: Presented at European Particle Accelerator Conference (EPAC 06), Edinburgh, Scotland, 26-30 Jun 2006
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCELERATORS; ALGORITHMS; ARCHITECTURE; IMPEDANCE; KLYSTRONS; PERFORMANCE; PROCESSING; RF SYSTEMS; RING CURRENTS; SIMULATION; STABILITY; VALIDATION; Accelerators,ACCPHY, ACCSYS, ENG, INST

Citation Formats

Rivetta, Claudio, Mastorides, T., Fox, J.D., Teytelman, D., Van Winkle, D., and /SLAC. Modeling and Simulation of Longitudinal Dynamics for LER-HER PEP II Rings. United States: N. p., 2007. Web.
Rivetta, Claudio, Mastorides, T., Fox, J.D., Teytelman, D., Van Winkle, D., & /SLAC. Modeling and Simulation of Longitudinal Dynamics for LER-HER PEP II Rings. United States.
Rivetta, Claudio, Mastorides, T., Fox, J.D., Teytelman, D., Van Winkle, D., and /SLAC. Tue . "Modeling and Simulation of Longitudinal Dynamics for LER-HER PEP II Rings". United States. doi:. https://www.osti.gov/servlets/purl/900593.
@article{osti_900593,
title = {Modeling and Simulation of Longitudinal Dynamics for LER-HER PEP II Rings},
author = {Rivetta, Claudio and Mastorides, T. and Fox, J.D. and Teytelman, D. and Van Winkle, D. and /SLAC},
abstractNote = {A time domain modeling and simulation tool for beam-cavity interactions in LER and HER rings at PEP II are presented. The motivation for this tool is to explore the stability margins and performance limits of PEP II RF systems at higher currents and upgraded RF configurations. It also serves as test bed for new control algorithms and can define the ultimate limits of the architecture. The time domain program captures the dynamical behavior of the beam-cavity interaction based on a reduced model. The ring current is represented by macro-bunches. Multiple RF station in the ring are represented via one or two macro-cavities. Each macro-cavity captures the overall behavior of all the 2 or 4 cavity RF station. Station models include nonlinear elements in the klystron and signal processing. This allows modeling the principal longitudinal impedance control loops interacting with the longitudinal beam model. Validation of simulation tool is in progress by comparing the measured growth rates for both LER and HER rings with simulation results. The simulated behavior of both machines at high currents are presented comparing different control strategies and the effect of non-linear klystrons in the growth rates.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 06 00:00:00 EST 2007},
month = {Tue Mar 06 00:00:00 EST 2007}
}

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