Echo spectroscopy of atomic dynamics in a Gaussian trap via phase imprintsD. Oblak, J. Appel, P. J. Windpassinger, U. B. Hoff, N. Kjærgaard and E. S. PolzikEur. Phys. J. D, 50 1 (2008) 67-73DOI: https://doi.org/10.1140/epjd/e2008-00192-1