Measurement of B{sup 0}/Bbar{sup 0} {right arrow}J/{psi} K(0 over s) decay asymmetry using same-side b-flavor tagging

We present a measurement of the time-dependent asymmetry in the rate for {anti B}{sup 0} versus B{sup 0} decays to J/{psi}K{sup 0}{sub s}. The data sample consists of 198 {+-} 17 B{sup 0}/{anti B}{sup 0} decays collected by the CDF detector in p{anti p} collisions at the Fermilab Tevatron, where the initial b flavor has been determined by a same-side flavor tagging technique. This asymmetry is interpreted in the Standard Model as a measurement of the CP-violation parameter sin(2{beta}). Our analysis results in sin(2{beta}) = 1:8 {+-} 1:1(stat) {+-} 0:3(syst).