Search For Scalar Contributions To The K-38m Beta(+)-Nu Correlation In A Magneto-Optic Trap

We have begun a program to test weak interaction symmetries by trapping in a Magneto-optic trap (MOT) isotopes produced at the TRIUMF cyclotron's on-line separator TISOL. We are searching for non-Standard Model scalar contributions to the beta(+) - nu correlation in the 0(+) --> 0(+) Fermi decay of K-38m. We have trapped K-38m and K-37 in a vapor-cell MOT, arid transferred them to a second MOT which houses the nuclear detectors. The recoiling nuclei freely escape the trap and are detected in a microchannel plate; simultaneous detection of the beta(+) momentum allows reconstruction of the nu momentum. Approximately 500,000 beta(+)-recoil coincidences have been observed in June 1998; analysis is proceeding.