# 36th Annual International Symposium on Lattice Field Theory

Jul 22 – 28, 2018
Kellogg Hotel and Conference Center
EST timezone

## D meson semileptonic decay form factors at $q^2 = 0$

Jul 26, 2018, 8:30 AM
20m
103 (Kellogg Hotel and Conference Center)

### 103

#### Kellogg Hotel and Conference Center

219 S Harrison Rd, East Lansing, MI 48824
Weak Decays and Matrix Elements

### Speaker

Dr Ruizi Li (Indiana University)

### Description

We calculate $D \rightarrow Kl\nu, \pi l\nu$ vector form factors $f_+^{K/\pi}$ at zero-momentum transfer, using MILC's $N_f = 2+1+1$ HISQ ensembles at four lattice spacings, $a \approx 0.042, 0.06, 0.09, 0.12$ fm, and various HISQ quark masses down to the (degenerate) physical light quark mass. We use the kinematic constraint $f_+= f_0$ at $q^2 = 0$ to determine the vector form factor from our study of the scalar current which yields $f_0$. We use hard pion/kaon SU(3) heavy-meson-staggered $\chi$PT and Symanzik effective theory to fit the data and extrapolate the form factors to the physical point. We improve the precision achieved in existing lattice calculations of the vector form factors at $q^2=0$. We also determine the CKM matrix elements $|V_{cs}|$, $|V_{cd}|$ using recent experimental results and test second row unitarity.

### Primary author

Dr Ruizi Li (Indiana University)

### Co-authors

Prof. Aida El-Khadra (University of Illinois at Urbana-Champaign) Dr Andreas Kronfeld (Fermilab) Carleton DeTar (University of Utah) Prof. Claude Bernard (Washington University) Prof. Doug Toussaint (University of Arizona) Dr Elvira Gamiz (University of Granada) Dr Ruth Van de Water (Fermilab) Steven Gottlieb (Indiana Univ.)

 Slides