MEASUREMENT OF THE B{sup 0} LIFETIME USING PARTIAL RECONSTRUCTION

Abstract

We present here the first measurement of the B{sup 0} lifetime using partial reconstruction in B{sup 0} {yields} D*{sup -} {rho}{sup +} decay. A sample of approximately 5500 B{sup 0} {yields} D*{sup -} {rho}{sup +} events were identified among 22.7 million B{bar B} pairs collected by the BABAR experiment during the years 1999-2000. With this data, the B{sup 0} lifetime is measured to be 1.616 {+-} 0.064 {+-} 0.075 ps, in good agreement with the world average. This measurement demonstrates that is it possible to use this technique to perform time-dependent B{sup 0} decay analysis that is central to the measurement of the charge-parity (CP) asymmetries. Investigation of CP observables through measurements of the decays of B{sup 0} mesons is the primary goal of the BABAR experiment at the PEP-II storage ring located at Stanford Linear Accelerator Center (SLAC). As the B{sup 0} particle decays to final states that are directly sensitive to the CP parameter {gamma} are highly suppressed, a promising alternative approach is to use the final state B{sup 0} {yields} D*h. Using the partial event reconstruction analysis method it is possible to compensate for the small CP asymmetries in this decay.