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arXiv · 0711.0337

Linear Stark Shifts to Measure the Fr Weak Nuclear Charge with Small Atom Samples

Marie-Anne Bouchiat
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Abstract

We study the chirality of ground-state alkali atoms in E and B fields, dressed with a circularly-polarized laser beam close-detuned from an E-field-assisted forbidden transition, such as 7S-8S in Fr. We predict a parity violating energy shift of their sublevels, linear in E, and the weak nuclear charge Q_W$. A dressing beam of 10 kW/cm$^2$ at 506 nm produces a shift of $\sim100 μ$Hz at E=100 V/cm, B $\gtrsim$30 mG. It should be observable with $\sim 10^4$ Fr atoms confined in an optical dipole trap. We discuss optimal conditions, parameter reversals and a calibration procedure to measure $Q_W$.

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Marie-Anne Bouchiat. 2007-11-05. Linear Stark Shifts to Measure the Fr Weak Nuclear Charge with Small Atom Samples. https://doi.org/10.1103/physrevlett.100.123003

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