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Title: Emittance growth due to Tevatron flying wires

Abstract

During Tevatron injection, Flying Wires have been used to measure the transverse beam size after each transfer from the Main Injector in order to deduce the transverse emittances of the proton and antiproton beams. This amounts to 36 + 9 = 45 flies of each of 3 wire systems, with an individual wire passing through each beam bunch twice during a single ''fly''. below they estimate the emittance growth induced by the interaction of the wires with the particles during these measurements. Changes of emittance from Flying Wire measurements conducted during three recent stores are compared with the estimations.

Authors:
;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
15017291
Report Number(s):
FERMILAB-BEAMS-DOC-1199 FERMILAB-EXP-204
TRN: US0604910
DOE Contract Number:
AC02-76CH03000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ANTIPROTON BEAMS; FERMILAB TEVATRON; FLIES; PROTONS; Accelerators

Citation Formats

Syphers, M, and Eddy, Nathan. Emittance growth due to Tevatron flying wires. United States: N. p., 2004. Web. doi:10.2172/15017291.
Syphers, M, & Eddy, Nathan. Emittance growth due to Tevatron flying wires. United States. doi:10.2172/15017291.
Syphers, M, and Eddy, Nathan. 2004. "Emittance growth due to Tevatron flying wires". United States. doi:10.2172/15017291. https://www.osti.gov/servlets/purl/15017291.
@article{osti_15017291,
title = {Emittance growth due to Tevatron flying wires},
author = {Syphers, M and Eddy, Nathan},
abstractNote = {During Tevatron injection, Flying Wires have been used to measure the transverse beam size after each transfer from the Main Injector in order to deduce the transverse emittances of the proton and antiproton beams. This amounts to 36 + 9 = 45 flies of each of 3 wire systems, with an individual wire passing through each beam bunch twice during a single ''fly''. below they estimate the emittance growth induced by the interaction of the wires with the particles during these measurements. Changes of emittance from Flying Wire measurements conducted during three recent stores are compared with the estimations.},
doi = {10.2172/15017291},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2004,
month = 6
}

Technical Report:

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  • Emittance growth due to noise from a transverse beam feedback system are discussed. A theory for calculating emittance growth rate as a function of the feedback system's measured open loop transfer function is derived. A simple feedback system was installed, measured, and tested in the Fermilab Tevatron, and the emittance growth rate results agree very closely with the theory.
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