Vtd from hadronic two-body B decays

Certain hadronic two-body decays of B mesons are dominated by penguin diagrams. The ratios of rates for several such decays, including Λ(B0 → K∗0K0)Λ(B0 → φK0), Λ(B0 → K∗0K∗0)Λ(B0 → φK∗0), Λ(B+ → K∗0K+)Λ(B+ → φK+), and Λ(B+ → K∗0K∗+)Λ(B+ → φK∗+), can provide information on the ratio of Cabibbo-Kobayashi-Maskawa (CKM) elements |VtdVts| in a manner complementary to other proposed determinations. SU(3) breaking effects cancel in some ratios. The cases of neutral B decays are free of corrections from small annihilation terms.