skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Comment on 'Improved Experimental Limit on the Electric Dipole Moment of the Neutron'

Abstract

A Comment on the Letter by C. A. Baker et al., [Phys. Rev. Lett. 97, 131801 (2006)]. The authors of the Letter offer a Reply.

Authors:
;  [1];  [2]
  1. Yale University Department of Physics Box 208120 New Haven, Connecticut 06520-8120 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20951219
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 14; Other Information: DOI: 10.1103/PhysRevLett.98.149101; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRIC DIPOLE MOMENTS; MEASURING METHODS; NEUTRONS

Citation Formats

Lamoreaux, S. K., Golub, R., and North Carolina State University Department of Physics Campus Box 8202 Raleigh, North Carolina 27695-8202. Comment on 'Improved Experimental Limit on the Electric Dipole Moment of the Neutron'. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.149101.
Lamoreaux, S. K., Golub, R., & North Carolina State University Department of Physics Campus Box 8202 Raleigh, North Carolina 27695-8202. Comment on 'Improved Experimental Limit on the Electric Dipole Moment of the Neutron'. United States. doi:10.1103/PHYSREVLETT.98.149101.
Lamoreaux, S. K., Golub, R., and North Carolina State University Department of Physics Campus Box 8202 Raleigh, North Carolina 27695-8202. Fri . "Comment on 'Improved Experimental Limit on the Electric Dipole Moment of the Neutron'". United States. doi:10.1103/PHYSREVLETT.98.149101.
@article{osti_20951219,
title = {Comment on 'Improved Experimental Limit on the Electric Dipole Moment of the Neutron'},
author = {Lamoreaux, S. K. and Golub, R. and North Carolina State University Department of Physics Campus Box 8202 Raleigh, North Carolina 27695-8202},
abstractNote = {A Comment on the Letter by C. A. Baker et al., [Phys. Rev. Lett. 97, 131801 (2006)]. The authors of the Letter offer a Reply.},
doi = {10.1103/PHYSREVLETT.98.149101},
journal = {Physical Review Letters},
number = 14,
volume = 98,
place = {United States},
year = {Fri Apr 06 00:00:00 EDT 2007},
month = {Fri Apr 06 00:00:00 EDT 2007}
}
  • An experimental search for an electric dipole moment (EDM) of the neutron has been carried out at the Institut Laue-Langevin, Grenoble. Spurious signals from magnetic-field fluctuations were reduced to insignificance by the use of a cohabiting atomic-mercury magnetometer. Systematic uncertainties, including geometric-phase-induced false EDMs, have been carefully studied. The results may be interpreted as an upper limit on the neutron EDM of vertical bar d{sub n} vertical bar <2.9x10{sup -26}e cm (90% C.L.)
  • New results are reported in our search for the electric dipole moment [ital d][sub [ital e]] of the electron in the ground 6 [sup 2][ital P][sub 1/2] state of [sup 205]Tl. The atomic-beam magnetic resonance method is employed with separated oscillating fields. A magnetic field [bold B] defines the axis of quantization, and an electric field [bold E], parallel to [bold B], is applied in the region between the oscillating fields. Laser optical pumping is used for state selection and analysis, and the signal is fluorescence accompanying the decay of excited atoms in the analyzer region. The signature of amore » nonzero electric dipole moment is a dependence of the signal on the [ital P],[ital T]-odd rotational invariant [bold E][center dot][bold B] ([ital P] and [ital T] denote parity and time reversal, respectively). Two counterpropagating atomic beams are employed to reduce a systematic effect due to the motional magnetic field [bold E][times][bold v]/[ital c]. Auxiliary experiments are performed to isolate and eliminate residual sources of systematic error. The result is [ital d][sub [ital e]]=[1.8[plus minus]1.2(statistical)[plus minus]1.0(systematic)][times]10[sup [minus]27] e cm. A detailed discussion is given of the experimental method, sources of systematic error and their elimination, and results.« less
  • An experimental measurement of the electric dipole moment of the neutron by a neutron-beam magnetic resonance method is described. The result of the experiment is that the electric dipole moment of the neutron equals the charge of the electron multiplied by a distance D - ( --0.1 of 2.4) x 10/sup -20/ cm. Consequently, if an electric dipole moment of the neutron exists and is associated with the spin angular momentum, its magnitude almost certainly corresponds to a value of D less than 5 x 10/sup -20/ cm. (auth)