B-FACTORY CONSTRAINTS ON ISOSINGLET DOWN QUARK MIXING, AND PREDICTIONS FOR OTHER CP-VIOLATING EXPERIMENTS

In the main part of this paper are project forward to having B factory determinations of sin(2 beta) and sin(2 alpha), for which we take sev eral values. First, we use a joint chi(2) analysis of CKM experiments to constrain CKM matrix elements in the standard model, and experiment s on the angles alpha, beta and gamma, and on x(s) and null CP asymmet ries. Then we invoke mixing to a new isosinglet down quark (as in E(6) ) which induces FCNC's that allow a Z(0) mediated contribution to B - (B) over bar mixing and which brings in new phases. We then repeat the chi(2) analysis, now including experimental constraints from FCNC's a s well, finding much larger ranges of prediction for the B factory. We then add projected B factory results on sin(2 beta) and sin(2 alpha) and repeat both analyses. In (rho, eta) and (x(s), sin(gamma)) plots f or the extra isosinglet down quark model, we find multiple regions tha t will require experiments on sin(gamma) and/or x(s) to decide between , and possibly to effectively bound out the extra down quark contribut ion.