Measurement of the magnetic field profile in the atomic fountain clock   FoCS-2 using Zeeman spectroscopy
  We report the evaluation of the second order Zeeman shift in the continuous atomic fountain clock FoCS-2. Because of the continuous operation and of its geometrical constraints, the methods used in pulsed fountains are not applicable. We use here time-resolved Zeeman spectroscopy to probe the magnetic field profile in the clock. The pulses of ac magnetic excitation allow us to spatially resolve the Zeeman frequency and to evaluate the Zeeman shift with a relative uncertainty smaller than 10E-16. 
Devenoges Laurent, Di Domenico Gianni, Stefanov Andr\'e, Jallageas   Antoine, Morel Jacques, S\"udmeyer Thomas, Thomann Pierre
physics.atom-ph