Measurement of

The goal of this new experiment is the observation and study of the CP violating decay if it occurs within the range of branching ratios predicted by the Standard Model (SM) centered on . Measurement of allows a clear test of the SM origin of CP violation and unambiguous determination of the complex phase parameter ( in the Wolfenstein parameterization) in the quark mixing matrix. Unlike other CP violating observables in the K system, only direct CP violation is involved and the decay rate can be calculated precisely in the SM. is also free of long-distance complications down to the level, so that short distance contributions, either SM or new physics, can be identified. The high intensity beam and special time structure expected to be available at the AGS make clean observation of potentially feasible.

• Proposed Agenda