Searching for new physics in the b -> d FCNC using B-s(0)(t) ->phi K-S andB-d(0)(t) -> K-0(K-0)over-bar

Time-dependent measurements of the decays B-s(0)(t) --> phi K-S and B-d(0)( t) --> K-0<(K-0)over bar> can be used to compare the weak phases of B-d(0)- <(B-d(0))over bar> mixing and the t-quark contribution to the b --> d pengu in. Since these two phases are equal in the standard model, any discrepancy would be a sign of new physics, specifically in the b --> d flavour-changi ng neutral current (FCNC). The method can be applied to other pairs of deca ys, such as B-s(0)(t) --> J/Psi K-S and B-d(0)(t) --> J/Psi pi(0). (C) 1999 Elsevier Science B.V. All rights reserved.