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Title: CORRECT TRACKING IN FFAGS.

Abstract

Fixed field alternating gradient accelerators have many features which require careful modeling in simulation. They accept beams over an extremely large momentum range, generally at least a factor of 2. They often use magnets whose lengths are comparable to their apertures. The beam often makes large angles with respect to the magnet axis and pole face normal. In some applications (muons in particular), the beam occupies a substantial fraction of the magnet aperture. The longitudinal dynamics in these machines often differ significantly from what one finds in more conventional machines such as synchrotrons. These characteristics require that simulation codes be careful to avoid inappropriate approximations in describing particle motion in FFAGs. One must properly treat the coordinate system geometry independently from the magnetic fields. One cannot blindly assume that phase space variables are small. One must take magnet end fields properly into account. Finally, one must carefully consider what it means to have a ''matched'' distribution that is injected into these machines.

Authors:
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
DOE/SC
OSTI Identifier:
881259
Report Number(s):
BNL-75717-2006-CP
R&D Project: 08778; KA1502030; TRN: US0602903
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Conference
Resource Relation:
Conference: FFAG WORKSHOP '05; KYOTO UNIVERSITY RESEARCH REACTOR INSTITUTE, KYOTO, JAPAN; 20051205 through 20051209
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCELERATORS; APERTURES; DISTRIBUTION; GEOMETRY; MAGNETIC FIELDS; MAGNETS; MUONS; PHASE SPACE; RESEARCH REACTORS; SIMULATION; SYNCHROTRONS

Citation Formats

BERG, J.S. CORRECT TRACKING IN FFAGS.. United States: N. p., 2006. Web.
BERG, J.S. CORRECT TRACKING IN FFAGS.. United States.
BERG, J.S. Mon . "CORRECT TRACKING IN FFAGS.". United States. doi:. https://www.osti.gov/servlets/purl/881259.
@article{osti_881259,
title = {CORRECT TRACKING IN FFAGS.},
author = {BERG, J.S.},
abstractNote = {Fixed field alternating gradient accelerators have many features which require careful modeling in simulation. They accept beams over an extremely large momentum range, generally at least a factor of 2. They often use magnets whose lengths are comparable to their apertures. The beam often makes large angles with respect to the magnet axis and pole face normal. In some applications (muons in particular), the beam occupies a substantial fraction of the magnet aperture. The longitudinal dynamics in these machines often differ significantly from what one finds in more conventional machines such as synchrotrons. These characteristics require that simulation codes be careful to avoid inappropriate approximations in describing particle motion in FFAGs. One must properly treat the coordinate system geometry independently from the magnetic fields. One cannot blindly assume that phase space variables are small. One must take magnet end fields properly into account. Finally, one must carefully consider what it means to have a ''matched'' distribution that is injected into these machines.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 30 00:00:00 EST 2006},
month = {Mon Jan 30 00:00:00 EST 2006}
}

Conference:
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  • Abstract not provided.
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  • When large transverse and longitudinal emittances are to be transported through a circular machine, extremely rapid acceleration holds the advantage that the beam becomes immune to nonlinear resonances because there is insufficient time for amplitudes to build up. Uncooled muon beams exhibit large emittances and require fast acceleration to avoid decay losses and would benefit from this style of acceleration. The approach here employs a fixed-field alternating gradient or FFAG magnet structure and a fixed frequency acceleration system. Acceptance is enhanced by the use only of linear lattice elements, and fixed-frequency rf enables the use of cavities with large shuntmore » resistance and quality factor.« less
  • Muon acceleration is one of the more difficult stages to develop for a Neutrino Factory or Muon Collider. The large transverse and longitudinal admittances which must be designed into the system and the rapidity with which acceleration must take place because of muon decay preclude the use of conventional synchrotron design. The approach here employs fixed-field architectures for muon acceleration; specifically, a fixed-field alternating gradient or FFAG accelerator. This paper explores the FFAG option, in particular addressing an adjustment in the rf phase which, although characteristic of fixed-field machines, becomes problematic in the context of rapid acceleration.
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