Resonant Five-body Recombination in an Ultracold Gas of Bosonic Atoms
  We combine theory and experiment to investigate five-body recombination in an ultracold gas of atomic cesium at negative scattering length. A refined theoretical model, in combination with extensive laboratory tunability of the interatomic interactions, enables the five-body resonant recombination rate to be calculated and measured. The position of the new observed recombination feature agrees with a recent theoretical prediction and supports the prediction of a family of universal cluster states at negative $a$ that are tied to an Efimov trimer. 
A. Zenesini, B. Huang, M. Berninger, S. Besler, H.-C. N\"agerl, F.   Ferlaino, R. Grimm, Chris H. Greene and J. von Stecher
cond-mat.quant-gas