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Title: A search for the electric dipole of the electron

Abstract

We report a new upper limit on the electric dipole moment (EDM) of the electron of d{sub e} = 0.1 {plus minus} 3.2 {times} 10{sup {minus}26} e-cm. This precision is one hundred times better than any previously published limit and a factor of two better than that of unofficial reports. Recently there has been a great deal of theoretical interest in the possibility of a non-zero electron EDM. Models such as the left-right-symmetric Standard Model and an off-standard'' model with new heavy neutrinos are constrained by the new limit on d{sub e}. A non-zero electron EDM would violate the time reversal and parity space-time symmetries. T-violation was observed in neutral kaon decay and is still not fully explained by the Standard Model. Our experimental technique involves searching for an energy shift, linear in applied electric field, between the m{sub F} = 1 and m{sub F} = {minus}1 magnetic sublevels of the F=1 hyperfine level of the 6{sup 2}P{sub 1/2} ground state of atomic thallium. If the electron has a non-zero EDM, this thallium state will exhibit an atomic electric dipole moment that is roughly 600 times larger. The energy shift is detected with the technique of magnetic resonance spectroscopy, employingmore » separated oscillating fields, applied to an atomic beam of thallium. In the approach, any relative phase-shift between the m{sub F} = {plus minus}1 components of the F=1 wavefunction acquired by the atom as it travels through an electric field is detected through interference with two separate oscillating magnetic fields located on either side of the electric field. The new level of precision is achieved through several improvements on previous experiments including employment of a vertical apparatus, two opposing atomic beams, and optical pumping for atomic state selection and analysis.« less

Authors:
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
DOE/ER
OSTI Identifier:
5540639
Report Number(s):
LBL-27723
ON: DE90001572; TRN: 89-028701
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Technical Report
Resource Relation:
Other Information: Thesis (Ph.D.)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 74 ATOMIC AND MOLECULAR PHYSICS; ELECTRONS; ELECTRIC DIPOLE MOMENTS; CP INVARIANCE; ELECTRIC FIELDS; MAGNETIC FIELDS; MEASURING METHODS; OPTICAL PUMPING; POLARIZATION; STANDARD MODEL; WAVE FUNCTIONS; DIPOLE MOMENTS; ELECTRIC MOMENTS; ELEMENTARY PARTICLES; FERMIONS; FUNCTIONS; INVARIANCE PRINCIPLES; LEPTONS; MATHEMATICAL MODELS; PARTICLE MODELS; PUMPING; UNIFIED GAUGE MODELS; 645102* - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties; 640302 - Atomic, Molecular & Chemical Physics- Atomic & Molecular Properties & Theory

Citation Formats

Abdullah, K F. A search for the electric dipole of the electron. United States: N. p., 1989. Web. doi:10.2172/5540639.
Abdullah, K F. A search for the electric dipole of the electron. United States. https://doi.org/10.2172/5540639
Abdullah, K F. 1989. "A search for the electric dipole of the electron". United States. https://doi.org/10.2172/5540639. https://www.osti.gov/servlets/purl/5540639.
@article{osti_5540639,
title = {A search for the electric dipole of the electron},
author = {Abdullah, K F},
abstractNote = {We report a new upper limit on the electric dipole moment (EDM) of the electron of d{sub e} = 0.1 {plus minus} 3.2 {times} 10{sup {minus}26} e-cm. This precision is one hundred times better than any previously published limit and a factor of two better than that of unofficial reports. Recently there has been a great deal of theoretical interest in the possibility of a non-zero electron EDM. Models such as the left-right-symmetric Standard Model and an off-standard'' model with new heavy neutrinos are constrained by the new limit on d{sub e}. A non-zero electron EDM would violate the time reversal and parity space-time symmetries. T-violation was observed in neutral kaon decay and is still not fully explained by the Standard Model. Our experimental technique involves searching for an energy shift, linear in applied electric field, between the m{sub F} = 1 and m{sub F} = {minus}1 magnetic sublevels of the F=1 hyperfine level of the 6{sup 2}P{sub 1/2} ground state of atomic thallium. If the electron has a non-zero EDM, this thallium state will exhibit an atomic electric dipole moment that is roughly 600 times larger. The energy shift is detected with the technique of magnetic resonance spectroscopy, employing separated oscillating fields, applied to an atomic beam of thallium. In the approach, any relative phase-shift between the m{sub F} = {plus minus}1 components of the F=1 wavefunction acquired by the atom as it travels through an electric field is detected through interference with two separate oscillating magnetic fields located on either side of the electric field. The new level of precision is achieved through several improvements on previous experiments including employment of a vertical apparatus, two opposing atomic beams, and optical pumping for atomic state selection and analysis.},
doi = {10.2172/5540639},
url = {https://www.osti.gov/biblio/5540639}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 01 00:00:00 EDT 1989},
month = {Tue Aug 01 00:00:00 EDT 1989}
}