Lattice2010

Session

Parallel 29: Weak decays and matrix elements

15 Jun 2010, 14:30

Villasimius, Sardinia

102. $B \to D^*l\nu$ at zero recoil: an update

Andreas S. Kronfeld (Fermilab)

15/06/2010, 14:30

Weak decays and matrix elements

We present an update of our calculation of the form factor for $B\to D^* l \nu$ at zero recoil, with higher statistics and further, finer, lattices. As before, we use the Fermilab action for $b$ and $c$ quarks, the asqtad staggered action for light valence quarks, and the MILC ensembles for gluons and light quarks (L\"uscher-Weisz married to 2+1 rooted staggered sea quarks).

92. D to K semi-leptonic form factors from HISQ light and charm quarks

Heechang Na (The Ohio State University)

15/06/2010, 14:50

Weak decays and matrix elements

We investigate D to Kl\nu semi-leptonic decays using HISQ light and charm quarks on the MILC coarse and fine lattices. Using PCVC allows us to extract the form factors with no need for operator renormalization. We employ random-wall sources and simultaneous multi-T fits, in order to reduce the statistical errors. By caring out consistency checks, we successfully re-produce all meson...

327. Form factors of the D -> pion and D -> K semileptonic decays

Stefano Di Vita (University of Rome III and INFN - Roma Tre)

15/06/2010, 15:10

Weak decays and matrix elements

We present lattice results for the form factors relevant in the D -> pion and D -> K semileptonic decays obtained from simulations with two flavors of dynamical twisted-mass fermions. Results at four values of the lattice spacing, ranging from ~ 0.05 up to ~ 0.1 fm, allow a careful study of the discretization effects. The application of Heavy Meson Chiral Perturbation Theory provides an...

177. Semileptonic decays of K and D mesons in 2+1 flavor QCD

Elvira Gamiz (Fermilab)

15/06/2010, 15:30

Weak decays and matrix elements

The experimentally measured rates of the semileptonic decays K to pi l nu and D to K(pi) l nu can be combined with lattice calculations of the associated form factors to precisely extract the CKM matrix elements |V_{us}| and |V_{cs(d)}|. We report on the status of form factor calculations with Fermilab charm quarks and staggered light quarks on the 2+1 flavor asqtad staggered MILC ensembles....

326. SU(2) ChPT analysis of the scalar and vector form factors of the kaon semileptonic decay obtained from twisted-mass fermions with Nf = 2

Lorenzo Orifici (University of Rome III and INFN - Roma Tre)

15/06/2010, 15:50

Weak decays and matrix elements

We investigate the form factors relevant in the K -> pion semileptonic decays using maximally twisted-mass fermions with two flavors of dynamical quarks. The simulations cover pion masses as light as 260 MeV and four values of the lattice spacing, from ~ 0.05 up to ~ 0.1 fm, which allow to compute accurately the continuum limit. SU(2) Chiral Perturbation Theory is applied to the...