Measurement of a false electric dipole moment signal from 199Hg atoms exposed to an inhomogeneous magnetic field
1 ETH Zürich, Institute for Particle
2 Paul Scherrer Institute (PSI), 5232 Villigen-PSI, Switzerland
3 Hans Berger Department of Neurology, Jena University Hospital, 07747 Jena, Germany
4 Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX, UK
5 LPC Caen, ENSICAEN, Université de Caen Basse-Normandie, CNRS/IN2P3, Caen, France
6 Marian Smoluchowski Institute of Physics, Jagiellonian University, 30–059 Cracow, Poland
7 Institut Laue-Langevin, Grenoble, France
8 Department of Physics and Astronomy, University of Sussex, Falmer, Brighton BN1 9QH, UK
9 Physics Department, University of Fribourg, 1700 Fribourg, Switzerland
10 Institut für Physik, Johannes–Gutenberg–Universität, 55128 Mainz, Germany
11 LPSC, Université Grenoble Alpes, CNRS/IN2P3, Grenoble, France
12 Henryk Niedwodniczański Institute for Nuclear Physics, 31–342 Cracow, Poland
13 Instituut voor Kern – en Stralingsfysica, University of Leuven, 3001 Leuven, Belgium
14 CSNSM, Université Paris Sud, CNRS/IN2P3, Orsay Campus, France
a Present address: University of Washington, Seattle WA, USA.
b Present address: Max-Planck-Institute of Quantum Optics, Garching, Germany.
c Present address: LPSC, Grenoble, France.
d Present address: Hauptstrasse 60, 4455 Zunzgen, Switzerland.
e On leave from INRNE, Sofia, Bulgaria.
f On leave from PNPI, St. Petersburg, Russia.
g e-mail: email@example.com
h Present address: Rilkeplatz 8/9, 1040 Vienna, Austria.
i Present address: Michigan State University, East-Lansing, USA.
k e-mail: firstname.lastname@example.org
Received in final form: 31 July 2015
Published online: 6 October 2015
We report on the measurement of a Larmor frequency shift proportional to the electric-field strength for 199Hg atoms contained in a volume permeated with aligned magnetic and electric fields. This shift arises from the interplay between the inevitable magnetic field gradients and the motional magnetic field. The proportionality to electric-field strength makes it apparently similar to an electric dipole moment (EDM) signal, although unlike an EDM this effect is P- and T-conserving. We have used a neutron magnetic resonance EDM spectrometer, featuring a mercury co-magnetometer and an array of external cesium magnetometers, to measure the shift as a function of the applied magnetic field gradient. Our results are in good agreement with theoretical expectations.
Key words: Atomic Physics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2015