We report on the status of the Fermilab-MILC calculation of the form factor f+ Kπ (q2 = 0), needed to extract the CKM matrix element |Vus| from experimental data on K semileptonic decays. The HISQ formulation is used in the simulations for the valence quarks, while the sea quarks are simulated with the asqtad action (MILC Nf = 2 + 1 configurations). We discuss the general methodology of the calculation, including the use of twisted boundary conditions to get values of the momentum transfer close to zero and the different techniques applied for the correlators fits. We present initial results for lattice spacings a ≈ 0.12 fm and a ≈ 0.09 fm, and several choices of the light quark masses.
|Original language||English (US)|
|Journal||Proceedings of Science|
|State||Published - 2011|
|Event||29th International Symposium on Lattice Field Theory, Lattice 2011 - Squaw Valley, Lake Tahoe, United States|
Duration: Jul 10 2011 → Jul 16 2011
ASJC Scopus subject areas