Radio frequency association of heteronuclear Feshbach molecules
  We present a detailed analysis of the production efficiency of weakly bound heteronuclear KRb-Feshbach molecules using radio frequency association in a harmonic trap. The efficiency was measured in a wide range of temperatures, binding energies and radio frequencies. A comprehensive analytical model is presented, explaining the observed asymmetric spectra and achieving good quantitative agreement with the measured production rates. This model provides a deep understanding of the molecule association process and paves the way for future experiments which rely on Feshbach molecules e.g. for the production of deeply bound molecules. 
C. Klempt, T. Henninger, O. Topic, M. Scherer, L.Kattner, E. Tiemann,   W. Ertmer and J. Arlt