arXiv subjects
Publications and source records attributed to Chris T Sachrajda.
I present a selection of recent lattice results in flavourdynamics, including the status of the calculation of quark masses and a variety of weak matrix elements relevant for the determination of CKM matrix elements. Recent improvements in the momentum resolution of lattice computations and progress towards precise computations of $K\toππ$ decay amplitudes are also reviewed.
A possible explanation of the apparent disrepency between the theoretical prediction and experimental measurement of the ratio of lifetimes $τ(Λ_b)/τ(B_d)$ is that ``spectator effects'', which appear at $O(1/m_b^3)$ in the heavy quark expansion, contribute significantly. We investigate this possibility by computing the corresponding operator matrix elements in a lattice simulation. We find that spectator effects are indeed significant, but do not appear to be sufficiently large to account for the full discrepency. We stress, however, that this is an exploratory study, and it is important to check our conclusions on a larger lattice and using a larger sample of gluon configurations.