We calculate the BB parameter, relevant for B 0 –B0 mixing, from a lattice gauge theory simulation at β = 6.0. The bottom quarks are simulated in the static theory, the light quarks with Wilson fermions. Improved smearing functions produced by a variational technique, most, are used to reduce statistical errors and minimize excited-state contamination of the groundstate signal. We obtain BB(4.3...

We present a calculation of the two-loop helicity amplitudes for the processes H ! ggg and H ! gq q in the large-M t limit. In this limit the calculation can be performed in terms of one-loop diagrams containing an eeective Hgg operator. These amplitudes are required for the next-to-leading order (NLO) corrections to the Higgs transverse momentum distribution and the next-to-next-to-leading ord...