https://doi.org/10.1007/s100530170177
An atomic linear Stark shift violating P but not T arising from the electroweak nuclear anapole moment
1
Laboratoire Kastler Brossel (Laboratoire de l'Université Pierre et Marie
Curie et de l'École Normale Supérieure, associé au CNRS (UMR 8552).) , 24 rue
Lhomond, 75231 Paris Cedex 05, France
2
Laboratoire de Physique Théorique de l'École Normale Supérieure (UMR 8549: Unité Mixte du Centre National de la Recherche Scientifique
et de l'École Normale Supérieure.) ,
24 rue Lhomond, 75231 Paris Cedex 05, France
Received:
20
December
2000
Published online: 15 July 2001
We propose a direct method of detection of the nuclear anapole moment. It is
based on the existence of a linear Stark shift for alkali atoms in
their ground state perturbed by a quadrupolar interaction of uniaxial symmetry
around a direction 
and a magnetic field. This shift is characterized by the T-even
pseudoscalar 
. It involves on the one hand the anisotropy of the hyperfine interaction induced by the quadrupolar interaction and, on the other, the static electric dipole moment arising from electroweak interactions inside the nucleus. The case of ground state Cs atoms trapped in a uniaxial (hcp) phase of solid 4He is examined. From an explicit evaluation of both the hyperfine structure anisotropy and the static dipole deduced from recent empirical data about
the Cs nuclear anapole moment, we predict the Stark shift. It is three times the experimental upper bound to be set on the T-odd Stark shift of free Cs atoms in order to improve the present limit on the electron EDM.
PACS: 11.30.Er – Charge conjugation, parity, time reversal, and other discrete symmetries / 21.90.+f – Other topics in nuclear structure / 67.80.Mg – Defects, impurities, and diffusion / 31.15.Ct – Semi-empirical and empirical calculations (differential overlap, Hückel, PPP methods, etc.)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001
