Beams Document 2988-v1

DocDB Home ]  [ Search ] [ Last 20 Days ] [ List Authors ] [ List Topics ] [ List Events ]

Impact of Electric Current Fluctuations Arising from Power Supplies on Charged-Particle Beams

Document #:
Beams-doc-2988-v1
Document type:
Publication
Submitted by:
Phil S. Yoon
Updated by:
Phil S. Yoon
Document Created:
24 Jan 2008, 10:35
Contents Revised:
24 Jan 2008, 10:35
Metadata Revised:
24 Jan 2008, 10:35
Viewable by:
  • Public document
Modifiable by:

Quick Links:
Latest Version

Abstract:
Electric current fluctuations are
one type of unavoidable machine imperfections,
and induce magnetic-field perturbations
as a source of instabilities in accelerators.
This paper presents measurement-based methodology
of modeling the fluctuating electric current
arising from the power system of Fermilab's Booster
synchrotron to discuss the ramifications of
the presence of ripple current and space-charge
defocusing effects. We also present the method of
generating stochastic noise and the measurement
and analysis methods of ripple current and
offending electromagnetic interferences residing in
the Booster power system. This stochastic noise model,
accompanied by a suite of beam diagnostic calculations,
manifests that the fluctuating power-supply current,
when coupled to space charge and impinging upon a beam,
can substantially enhance beam degradation
phenomena---such as emittance growth and
halo formation---during the Booster injection period.
With idealized and uniform charge-density distribution,
fractional growth of rms emittances due to ripple current
under space charge turn out to be about 8 ~ 9
in both transverse planes over the injection period of
2.2 ms prior to beam acceleration.
Files in Document:
Authors:
DocDB Home ]  [ Search ] [ Last 20 Days ] [ List Authors ] [ List Topics ] [ List Events ]

DocDB Version 8.8.9, contact Beams Document Database Administrators