A New Search for the Neutron Electric Dipole Moment nEDM

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A New Search for theNeutron Electric Dipole
Moment (nEDM)
Martin Cooper, Los Alamos Co-spokesperson Contract
or Project Manager for the nEDM Project for
presentation to Pre-town Meeting on Fundamental
Symmetries and Neutrons Pasadena,
California December 7, 2006
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Collaboration
R. Alarcon, L. Baron-Palos Arizona State
University, Tempe, AZ, USA D. Budker, A.
Sushkov University of California at Berkeley,
Berkeley, CA 94720, USA R. Carr, B. Filippone, R.
McKeown, B. Plaster, R. Schmid California
Institute of Technology, Pasadena, CA 91125,
USA W. Chen, D. Dutta, H. Gao, K. Kramer, X.
Qian, Q. Ye, X. F. Zhu, X. Zong Duke University,
Durham NC 27708, USA F. Mezei Hahn-Meitner
Institut, D-14109 Berlin, Germany C.-Y. Liu, J.
Long, H.-O. Meyer, M. Snow Indiana University,
Bloomington, IN 47405, USA D. Beck, A. Esler, D.
Hertzog, P. Kammel, J.-C. Peng, S. Williamson, J.
Yoder University of Illinois, Urbana-Champaign,
IL 61801, USA W. Korsch University of Kentucky,
Lexington KY 40506, USA P. Barnes, J. Boissevain,
M. Cooper, M. Espy, T. Ito, A. Matlachov, W.
Sondheim, J. Torgerson, S. Wilburn Los Alamos
National Laboratory, Los Alamos, NM 87545, USA K.
Dow, D. Hassel, E. Ihloff, J. Kelsey, R. Milner,
R. Redwine Massachusetts Institute of Technology,
Cambridge, MA 02139, USA F. Dubose, R. Golub, C.
Gould, D. Haase, P. Huffman, E. Korobkina, C.
Swank, A. Young North Carolina State University,
Raleigh, NC 27695, USA V. Cianciolo, S.
Penttila Oak Ridge National Laboratory, Oak
Ridge, TN 37831, USA M. Hayden Simon-Fraser
University, Burnaby, BC, Canada V5A 1S6 C.
Crawford, G. Greene The University of Tennessee,
Knoxville, TN 37996, USA S. Lamoreaux, D.
McKinsey Yale University, New Haven, CT 06520, USA
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Goal
The overarching goal of the EDM project is to
construct an apparatus that will search for a
neutron EDM with a statistical sensitivity and
systematic uncertainty of 2 x 10-28 ecm (90
CL). The collaboration has selected the
cryogenic method of Golub and Lamoreaux and sited
the experiment on the UCN beam line of the FNPB
at ORNL.
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Fundamental Question Origin of Matter-Antimatter
Asymmetry in the Universe
¹ 0

WMAP CMB DATA
The cosmic microwave background implies the
universe has mostly unseen matter. A search for
dn will indicated whether that matter could be
supersymmetric particles.
Matter plus anti-matter are not balanced,
fortunately. A sensitive search for dn
may explain why the universe has more matter than
anti-matter.
Neutron EDM Microscopic effect with cosmic
significance!
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Supersymmetry
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Theory and Experiment
'50 '68 '84 '06 '16
? excluded ILL SNS
10-20 10-22 10-24 10-26 10-28
10-30 10-32 10-34 10-36
10-38 e-cm
Electromagnetic
Standard model
Theory as distributions EDM rules out theories SM
leaves room for discovery
Cosmology
SUSY f a/p
Left-right symmetric
Strong CP q parameter SUSY GUT Electro-weak
Baryogenesis
Multi-Higgs
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EDM Experiment - Vertical Section View
Dilution Refrigerator (DR 1 of 2)
He Purifier Assembly
3He Polarized Source
Upper Cryostat Services Port
Central LHe Volume (300mK, 1000 Liters)
Upper Cryostat
DR LHe Volume 450 Liters
Re-entrant Insert for Neutron Guide
5.6m
3He Injection Volume
Lower Cryostat
3He Injection Volume cos? Magnet
4 Layer µ-metal Shield
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Critical Path and Cost
Cost Range 17.6 19.8M Request 18.5M