Preparation of an ultra-cold sample of ammonia molecules for precision   measurements
  We present experiments in which an ultra-cold sample of ammonia molecules is released from an electrostatic trap and recaptured after a variable time. It is shown that, by performing adiabatic cooling before releasing the molecules and adiabatic re-compression after they are recaptured, we are able to observe molecules even after more than 10 ms of free expansion. A coherent measurement performed during this time will have a statistical uncertainty that decreases approximately as the inverse of the square root of the expansion time. This offers interesting prospects for high-resolution spectroscopy and precision tests of fundamental physics theories. 
Marina Quintero-P\'erez, Thomas E. Wall, Steven Hoekstra, Hendrick L.   Bethlem
physics.chem-ph physics.atom-ph