title: Electronic interaction anisotropy between open-shell lanthanide atoms and helium from cold collision experiment.
abstract: Based on measurements of the Zeeman relaxation in a cold gas of (3)He [C. I. Hancox, S. C. Doret, M. I. Hummon, L. Luo, and J. M. Doyle, Nature (London) 431, 281 (2004)], we show that the electronic interaction anisotropy between rare-earth atoms with nonzero electronic orbital angular momenta and helium is extremely small. The interaction of the rare-earth atoms with He gives rise to several adiabatic potentials with different electronic symmetries. It is demonstrated that the energy splitting between these potentials does not exceed 0.09 cm(-1) at interatomic distances larger than the turning point for collisions at 0.8 K, including the region of the van der Waals interaction minima.
authors.affiliation: Harvard-Massachusetts Institute of Technology Center for Ultracold Atoms, Department of Physics, Harvard University, Cambridge, 02138, USA. rkrems@chem.ubc.ca
authors.forename: R V
authors.initials: RV
authors.lastname: Krems
authors.forename: A A
authors.initials: AA
authors.lastname: Buchachenko