May 14 – 17, 2012
University of Hawai'i at Manoa, EWC
Pacific/Honolulu timezone

D to K and D to pi FF and |V_cs| from Lattice QCD

May 16, 2012, 1:30 PM
20m
Keoni Room (University of Hawai'i at Manoa, EWC)

Keoni Room

University of Hawai'i at Manoa, EWC

Imin Conference Center at the East-West Center 1777 East-West Road Honolulu, Hawaii 96822

Speaker

Jonna Koponen (University of Glasgow)

Description

Chair: Jason Kumar (UH)

Abstract:
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, and extract the CKM matrix element |V_cs|. 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.

Presentation materials