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A high-field adiabatic fast passage ultracold neutron spin flipper for the UCNA experiment

Holley, A. T. and Broussard, L. J. and Davis, J. L. and Hickerson, K. and Ito, T. M. and Liu, C.-Y. and Lyles, J. T. M. and Makela, M. and Mammei, R. R. and Mendenhall, M. P. and Morris, C. L. and Mortensen, R. and Pattie, R. W. and Rios, R. and Saunders, A. and Young, A. R. (2012) A high-field adiabatic fast passage ultracold neutron spin flipper for the UCNA experiment. Review of Scientific Instruments, 83 (7). Art. No. 073505. ISSN 0034-6748.

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The UCNA collaboration is making a precision measurement of the β asymmetry (A) in free neutron decay using polarized ultracold neutrons (UCN). A critical component of this experiment is an adiabatic fast passage neutron spin flipper capable of efficient operation in ambient magnetic fields on the order of 1 T. The requirement that it operate in a high field necessitated the construction of a free neutron spin flipper based, for the first time, on a birdcage resonator. The design, construction, and initial testing of this spin flipper prior to its use in the first measurement of A with UCN during the 2007 run cycle of the Los Alamos Neutron Science Center's 800 MeV proton accelerator is detailed. These studies determined the flipping efficiency of the device, averaged over the UCN spectrum present at the location of the spin flipper, to be ϵ(overbar) = 0.9985(4).

Item Type:Article
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Ito, T. M.0000-0003-3494-6796
Morris, C. L.0000-0003-2141-0255
Additional Information:© 2012 American Institute of Physics. Received 14 May 2012; accepted 18 June 2012; published online 18 July 2012. We are indebted to the wonderful machinists in the NCSU PAMS machine shop as well as to Scott Currie and Henning Back. This work was supported in part by the National Science Foundation (NSF-0700491, NSF-0100689, NSF-0354970, NSF-0653222).
Funding AgencyGrant Number
Subject Keywords:neutron decay; neutron sources; proton accelerators; ultracold neutrons
Issue or Number:7
Classification Code:PACS: 29.25.Dz; 13.30.Ce; 14.20.Dh; 25.85.-w
Record Number:CaltechAUTHORS:20120925-150216625
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Official Citation:A high-field adiabatic fast passage ultracold neutron spin flipper for the UCNA experiment A. T. Holley, L. J. Broussard, J. L. Davis, K. Hickerson, T. M. Ito, C.-Y. Liu, J. T. M. Lyles, M. Makela, R. R. Mammei, M. P. Mendenhall, C. L. Morris, R. Mortensen, R. W. Pattie, R. Rios, A. Saunders, and A. R. Young, Rev. Sci. Instrum. 83, 073505 (2012), DOI:10.1063/1.4732822
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34366
Deposited By: Jason Perez
Deposited On:25 Sep 2012 23:23
Last Modified:09 Mar 2020 13:19

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