3 research outputs found
Light hadrons in 2+1 flavor lattice QCD
This talk will focus on recent results by the MILC collaboration from
simulations of light hadrons in 2+1 flavor lattice QCD. We have achieved high
precision results in the pseudoscalar sector, including masses and decay
constants, plus quark masses and Gasser-Leutwyler parameters from well
controlled chiral perturbation theory fits to our data. We also show
spectroscopy results for vector mesons and baryons.Comment: To appear in the proceedings of the First Meeting of the APS Topical
Group on Hadronic Physics, Fermilab, Batavia, Illinois, Oct. 24-26, 200
The D to K and D to pi semileptonic decay form factors from Lattice QCD
We present a new and very high statistics study of D and D_s semileptonic
decay form factors on the lattice. We work with MILC N_f=2+1 lattices and use
the Highly Improved Staggered Action (HISQ) for both the charm and the light
valence quarks. We use both scalar and vector currents to determine the form
factors f_0(q^2) and f_+(q^2) for a range of D and D_s form factors including
those for D to pi and D to K semileptonic decays. By using a phased boundary
condition we are able to tune accurately to q^2=0. We also compare the shape in
q^2 to that from experiment. We show that the form factors are very insensitive
to the spectator quark: D to K and D_s to eta_s form factors are essentially
the same, and the same is true for D to pi and D_s to K. This has important
implications when considering the corresponding B/B_s processes.Comment: 7 pages, 9 figures, talk given at the XXIX International Symposium on
Lattice Field Theory, July 10-16, 2011, Squaw Valley, Lake Tahoe, C
Measurement of the K_L \to \pi\mu\nu form factor parameters with the KLOE detector
Using 328 pb^{-1}of data collected at DAFNE corresponding to 1.8
million decays, we have measured the form factor
parameters. The structure of the vector-current provides information
about the dynamics of the strong interaction; its knowledge is necessary for
evaluation of the phase-space integral required for measuring the CKM matrix
element and for testing lepton universality in kaon decays. Using a
new parametrization for the vector and scalar form factors, we find
=\pt(25.7\pm 0.6),-3, and =\pt(14.0\pm 2.1),-3,. Our
result for , together with recent lattice calculations of ,
and , satisfies the Callan-Trieman relatio