Characterization of elastic scattering near a Feshbach resonance in 87Rb -: art. no. 010702

The s-wave scattering length for elastic collisions between Rb-87 atoms in the state \f,m(f)>=\1,1> is measured in the vicinity of a Feshbach resonance near 1007 G. Experimentally, the scattering length is determined from the mean-field-driven expansion of a Bose-Einstein condensate in a homogeneous magnetic field. The scattering length is measured as a function of the magnetic field and agrees with the theoretical expectation. The width of the resonance is determined to be 0.20(3) G, the position of the zero crossing of the scattering length is found at 1007.60(3) G.