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Title: Method and apparatus for recirculation with control of synchrotron radiation

Abstract

A method for controlling beam quality degradation from ISR and CSR and stabilizing the microbunching instability (.mu.BI) in a high brightness electron beam. The method includes providing a super-periodic second order achromat line with each super period being individually linearly achromatic and isochronous, setting individual superperiod tunes to rational fractions of an integer (such as 4.sup.th or 6.sup.th integers), setting individual bend angles to be as small as practical to reduce driving terms due to dispersion and dispersive angle, and setting bend radii as large enough to suppress ISR but not negatively affect the radial dependence of CSR. The method includes setting the structure of the individual superperiods to minimize bend plane beam envelope values in the dipoles to reduce betatron response to a CSR event at a dispersed location, increasing beam angular divergence, and creating dispersion nodes in the dipoles to similarly reduce response to CSR events, and limit R.sub.56 modulation in order to mitigate .mu.BI.

Inventors:
;
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1279738
Patent Number(s):
9,408,290
Application Number:
14/526,597
Assignee:
JEFFERSON SCIENCE ASSOCIATES, LLC (Newport News, VA) TJNAF
DOE Contract Number:
AC05-06OR23177
Resource Type:
Patent
Resource Relation:
Patent File Date: 2014 Oct 29
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; 42 ENGINEERING

Citation Formats

Douglas, David R., and Tennant, Christopher. Method and apparatus for recirculation with control of synchrotron radiation. United States: N. p., 2016. Web.
Douglas, David R., & Tennant, Christopher. Method and apparatus for recirculation with control of synchrotron radiation. United States.
Douglas, David R., and Tennant, Christopher. Tue . "Method and apparatus for recirculation with control of synchrotron radiation". United States. doi:. https://www.osti.gov/servlets/purl/1279738.
@article{osti_1279738,
title = {Method and apparatus for recirculation with control of synchrotron radiation},
author = {Douglas, David R. and Tennant, Christopher},
abstractNote = {A method for controlling beam quality degradation from ISR and CSR and stabilizing the microbunching instability (.mu.BI) in a high brightness electron beam. The method includes providing a super-periodic second order achromat line with each super period being individually linearly achromatic and isochronous, setting individual superperiod tunes to rational fractions of an integer (such as 4.sup.th or 6.sup.th integers), setting individual bend angles to be as small as practical to reduce driving terms due to dispersion and dispersive angle, and setting bend radii as large enough to suppress ISR but not negatively affect the radial dependence of CSR. The method includes setting the structure of the individual superperiods to minimize bend plane beam envelope values in the dipoles to reduce betatron response to a CSR event at a dispersed location, increasing beam angular divergence, and creating dispersion nodes in the dipoles to similarly reduce response to CSR events, and limit R.sub.56 modulation in order to mitigate .mu.BI.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 02 00:00:00 EDT 2016},
month = {Tue Aug 02 00:00:00 EDT 2016}
}

Patent:

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