Constraints on the CKM Angle Alpha in the B to Rho Rho Decays

Download or read book Constraints on the CKM Angle Alpha in the B to Rho Rho Decays written by H. Li and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using a data sample of 122 million {Upsilon}(4S) {yields} B{bar B} decays collected with BABAR detector at the PEP-II asymmetric B factory at SLAC, we measure the time-dependent-asymmetry parameters of the longitudinally polarized component in the B{sup 0} {yields} {rho}{sup +}{rho}{sup -} decay as C{sub L} = -0.23 {+-} 0.24(stat) {+-} 0.14(syst) and S{sub L} = -0.19 {+-} 0.33(stat) {+-} 0.11(syst). The B{sup 0} {yields} {rho}{sup 0}{rho}{sup 0} decay mode is also searched for in a data sample of about 227 million B{bar B} pairs. No significant signal is observed, and an upper limit of 1.1 x 10{sup -6} (90% C.L.) on the branching fraction is set. The penguin contribution to the CKM angle {alpha} uncertainty is measured to be 11{sup o}. All results are preliminary.