Eur. Phys. J. A (2007) 32: 525-529
https://doi.org/10.1140/epja/i2006-10433-9

PAVI 2006

Pump-probe measurement of atomic parity violation in cesium with a precision of 2.6%

Département de Physique de l'Ecole Normale Supérieure, Laboratoire Kastler Brossel, 24 Rue Lhomond, 75231, Paris cedex 05, France

^* e-mail: michel.lintz@oca.eu.

Received: 31 August 2006
Accepted: 18 March 2007
Published online: 13 July 2007

Abstract

We present the atomic parity violation measurements made in Cs vapour using a pump-probe scheme. After pulsed excitation of the 6S -7S forbidden transition in the presence of a longitudinal electric field, a laser beam resonant with one of the 7S -6P transitions stimulates the 7S atom emission for a duration of 20ns. The polarisation of the amplified probe beam is analysed. A seven-fold signature allows discrimination of the parity-violating linear dichroism, and real-time calibration by a similar, known, parity-conserving linear dichroism. The zero-field linear dichroism signal due to the magnetic dipole transition moment is observed for the first time, and used for in situ determination of the electric field. The result, ImE ₁ ^pv = (- 808±21)×10^-14 ea ₀ , is in perfect agreement with the corresponding, more precise measurement obtained by the Boulder group. A transverse field configuration with large probe amplification could bring atomic parity violation measurements to the 0.1% accuracy level.