"(a) shows an image in which the atom cloud has an e-1 radius of 36 µm in the trap x-y direction, and a peak absorption of 22%. These values correspond to 1.2 x 10 5 atoms with a temperature of 590 nK, giving N/Nc = 0.2. (b) shows the result of a separate load-evaporate cycle, giving N/Nc > 1, in which a distinct ringlike halo surrounding the absorption peak is observed."
The figure is from:
"Evidence of Bose-Einstein Condensation in an Atomic Gas with Attractive Interactions"
C. C. Bradley, C. A. Sackett, J. J. Tollett, and R. G. Hulet
Phys. Rev. Lett. 75, 1687 (1995).
Erratum published in 1997
C.C. Bradley, C.A. Sackett, J.J. Tollett, and R.G. Hulet,
Phys. Rev. Lett. 79, 1170 (1997)