The atom trapping team at Los Alamos has developed an efficient method of trapping radioactive atoms for both fundamental and applied research. This project makes use of advances in atomic physics that allows us to cool, trap and manipulate neutral atoms.
Our system uses a high-efficiency magneto-optical trap (MOT) that is coupled to an off-line mass separator. Once the desired atoms are trapped they can be detected with high sensitivity or transferred to another trap where a variety of experiments are performed. We are presently pursuing the following research areas:
Parity violation in beta-decay
We have recently demonstrated the trapping of polarized 82Rb (t1/2=75 s) to observe the parity-violating beta-nuclear spin correlation (setup and data). A 1% measurement of this correlation is planned to further test the maximal parity violating nature of the weak interaction and to search for new physics beyond the Standard Model.
For nonproliferation and environmental/dating applications, we are using the high selectivity and sensitivity of the mass separator–MOT system to detect small numbers of selected radioisotopes. To date we have trapped 135Cs (t1/2=2 x 10^6 y) and 137Cs (t1/2=30 y) and measured their isotopic ratio for the first time in a MOT with sensitivities as small as 10^7 atoms per sample.
Ultracold atoms / quantum degenerate matter
The ability to trap and cool different isotopes (both radioactive and stable) enables us to explore mixed fermionic and bosonic systems. In particular, we are working to produce a Bose-Einstein condensate of 87Rb and overlap it with a magnetically trapped cloud of fermionic 84Rb (t1/2=33 d) to investigate cold inter-isotopic collisions, explore sympathetic (i.e., collisional) cooling, and produce/study Fermi degenerate matter.
Updated 9/05 under LALP 05-096
Near-infrared picture of a fluorescing cloud of Cs atoms trapped in a MOT.