years without success since nature does not provide systems with the huge scattering lengths necessary. Credit: Illustration: Alan Stonebraker, vitaly Efimov predicted in 1970 1 that three particles can have an infinity of bound states even when no two of the three are separately bound together. Physics, The Pennsylvania State University, 1974,.S. 7 was carried out at essentially zero energy by fixing the scattering length a to some negative value and measuring the four-body recombination rate (the rate at which the system recombined into a lower-energy configuration). During her stay at jila as a postdoctoral associate in Chris Greene's group, she explored the behaviors of van der Waals clusters and Bose-Einstein condensates using Monte Carlo techniques. As a is tuned away from infinity, Efimov states are converted to four free atoms for a 0 and into B2BB for. Polyzou, university of Iowa. It was not only the low temperatures, which are essential for observing features related to the very weakly bound Efimov states, but also the ability to control the two-body s-wave scattering length that proved critical since Efimov states only appear in the limit of very. I like the idea of such meetings, and I like the idea of being able to encourage such interactions through this topical group.
Even more confounding to our intuition is the fact that making the underlying interactions between the three particles stronger decreases the number of three-body bound states from infinity to a finite value. The experiment that probably most captures the imagination, though, is producing and trapping these intriguing Efimov trimers for direct study. Although my training and degrees are in Chemistry my research is by nature interdisciplinary, and cuts across the boundaries between physics and chemistry. This line of experimentation has taken me in recent years to the GeV energy range at Jefferson Lab, the realm where three-body forces are about as strong as two-body forces, for wavelengths of the order of a few tenths of a Fermi, and to the. Positive a thus finds two lower thresholds for B2BB and B2B2. Associate Professor in the. Using ultracold cesium atoms as in their previous experiment, they have not only measured the four-body recombination rate, but also determined its dependence on the cesium-cesium scattering length. Starting from well-characterized two-body potentials, my goal is to develop and apply treatments that describe these systems accurately in terms of a few key quantities. National Science Summer School Darwin' - Biology Stream) now the National Youth Science Forum sponsored by Rotary Club Darwin - encouraged by my chemistry teacher Anne Donnelly. School of Mathematics and Physics at, the University of Queensland.