document: Table 1 lists 8 pairs of B decays. In fact, there are more decay pairs, since many of the particles in the final states can be observed as either pseudoscalar (P) or vector (V) mesons. Note that certain decays are written in terms of VV final states, while others are have PP states. There are three reasons for this. First, some decays involve a final-state π0. However, experimentally it will be necessary to find the decay vertices of the final particles. This is virtually impossible for a π0, and so we always use a ρ0. Second, some pairs of decays are related by SU(3) in the SM only if an (ss¯) quark pair is used. However, there are no P's which are pure (ss¯). The mesons η and η′ have an (ss¯) component, but they also have significant (uu¯) and (dd¯) pieces. As a result the b¯→s¯ and b¯→d¯ decays are not really related by SU(3) in the SM if the final state involves an η or η′. We therefore consider instead the vector meson ϕ which is essentially a pure (ss¯) quark state. Finally, we require that both B0 and B¯0 be able to decay to the final state. This cannot happen if the final state contains a single K0 (or K¯0) meson. However, it can occur if this final-state particle is an excited neutral kaon. In this case one decay involves K*0, while the other has K¯*0. Assuming that the vector meson is detected via its decay to ψKsπ0 (as in the measurement of sin2β via Bd0(t)→J/ψK*), then both B0 and B¯0 can decay to the same final state.
extractive_keyphrases: b0 b¯0 b decays decay decays excited neutral kaon final particles measurement of sin2β meson mesons quark sm η η′ ϕ ψksπ0
abstractive_keyphrases: decay pairs decay to the final state decay to ψksπ0 final-state particle find the decay vertices k¯*0 k*0 pairs of decays quark pair quark state vector meson