Improving extraction efficiency of the third integer resonant extraction using higher order multipoles
Abstract
The new accelerator complex at JPARC will operate with both high energy and very high intensity proton beams. With a design slow extraction efficiency of greater than 99% this facility will still be depositing significant beam power onto accelerator components [2]. To achieve even higher efficiencies requires some new ideas. The design of the extraction system and the accelerator lattice structure leaves little room for improvement using conventional techniques. In this report we will present one method for improving the slow extraction efficiency at JPARC by adding duodecapoles or octupoles to the slow extraction system. We will review the theory of resonant extraction, describe simulation methods, and present the results of detailed simulations. From our investigations we find that we can improve extraction efficiency and thereby reduce the level of residual activation in the accelerator components and surrounding shielding.
 Authors:
 Brookhaven National Lab. (BNL), Upton, NY (United States)
 High Energy Accelerator Research Organization (KEK), Tsukuba (Japan)
 Publication Date:
 Research Org.:
 Brookhaven National Laboratory (BNL), Upton, NY (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Nuclear Physics (NP) (SC26)
 OSTI Identifier:
 1349573
 Report Number(s):
 BNL1137082017IR
R&D Project: KBCH139; KB0202011
 DOE Contract Number:
 SC00112704
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 43 PARTICLE ACCELERATORS
Citation Formats
Brown, K. A., Schoefer, V., and Tomizawa, M. Improving extraction efficiency of the third integer resonant extraction using higher order multipoles. United States: N. p., 2017.
Web. doi:10.2172/1349573.
Brown, K. A., Schoefer, V., & Tomizawa, M. Improving extraction efficiency of the third integer resonant extraction using higher order multipoles. United States. doi:10.2172/1349573.
Brown, K. A., Schoefer, V., and Tomizawa, M. Thu .
"Improving extraction efficiency of the third integer resonant extraction using higher order multipoles". United States.
doi:10.2172/1349573. https://www.osti.gov/servlets/purl/1349573.
@article{osti_1349573,
title = {Improving extraction efficiency of the third integer resonant extraction using higher order multipoles},
author = {Brown, K. A. and Schoefer, V. and Tomizawa, M.},
abstractNote = {The new accelerator complex at JPARC will operate with both high energy and very high intensity proton beams. With a design slow extraction efficiency of greater than 99% this facility will still be depositing significant beam power onto accelerator components [2]. To achieve even higher efficiencies requires some new ideas. The design of the extraction system and the accelerator lattice structure leaves little room for improvement using conventional techniques. In this report we will present one method for improving the slow extraction efficiency at JPARC by adding duodecapoles or octupoles to the slow extraction system. We will review the theory of resonant extraction, describe simulation methods, and present the results of detailed simulations. From our investigations we find that we can improve extraction efficiency and thereby reduce the level of residual activation in the accelerator components and surrounding shielding.},
doi = {10.2172/1349573},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Mar 09 00:00:00 EST 2017},
month = {Thu Mar 09 00:00:00 EST 2017}
}

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