IMPLICATIONS OF THE TOP-QUARK MASS MEASUREMENT FOR THE CKM PARAMETERS, X(S) AND CP ASYMMETRIES

Motivated by the recent determination of the top quark mass by the CDF collaboration, m(t) = 174 +/- 10(-12)(+13) GeV, we review and update the constraints on the parameters of the quark flavour mixing matrix V-CKM in the standard model. In performing our fits, we use inputs from the measurements of the following quantities: (i) \epsilon\, the CP-violating parameter in K decays, (ii) Delta M(d), the mass difference due to the B-d(0)-<(B-d(0))over bar> mixing, (iii) the matrix elements \V-cb\ and \V-ub\, and (iv) B-hadron lifetimes. We find that the allowed region of the unitarity triangle is very large, mostly due to theoretical uncertainties. (This emphasizes the importance of measurements of CP-violating rate asymmetries in the B system.) Nevertheless, the present data do somewhat restrict the allowed values of the coupling constant product f(Bd)root (B) over cap(Bd) and the renormalization-scale-invariant bag constant (B) over cap(K). With the updated CKM matrix we present the currently-allowed range of the ratio /V-td/V-ts/, as well as the standard model predictions for the B-s(o)-<(B-s(0))over bar> mixing parameter x(s) and the quantities sin 2 alpha, sin2 beta and sin2 gamma, which characterize the CP-asymmetries in B-decays. The ALEPH collaboration has recently reported a significant improvement on the lower limit on the B-s(o)-<(B-s(0))over bar> mass difference, Delta M(s)/Delta M(d) > 11.3 (95% C.L.). This has interesting consequences for the CKM parameters which are also worked out.