Realisation of a Frequency Standard Using an Atomic Fountain
  We report the realisation and preliminary study of a frequency standard using a fountain of laser cooled caesium atoms. Our apparatus uses a magneto-optical trap as a source of cold atoms and optical pumping to prepare the atoms in the correct state before they enter the microwave cavity. 
A. Michaud, M. Chowdhury, K. P. Zetie, C. J. Cooper, G. Hillenbrand,   V. Lorent, A. Steane and C. J. Foot