PoS - Proceedings of Science
Volume 334 - The 36th Annual International Symposium on Lattice Field Theory (LATTICE2018) - Weak Decays and Matrix Elements
D meson semileptonic decay form factors at $q^2 = 0$
R. Li,* A. Bazavov, C. DeTar, C.W. Bernard, D. Du, A.X. El-Khadra, E. Gámiz, S. Gottlieb, U.M. Heller, J. Komijani, A.S. Kronfeld, L. J. Laiho, P.B. Mackenzie, E.T. Neil, T. Primer, J.N. Simone, R.L. Sugar, D. Toussaint, R.S. Van de Water, R. Zhou on behalf of Fermilab Lattice and MILC Collaborations
*corresponding author
Full text: pdf
Published on: May 29, 2019
Abstract
We discuss preliminary results for the vector form factors $f_+^{\{\pi,K\}}$ at zero-momentum transfer for the decays $D\to\pi\ell\nu$ and $D\to K \ell\nu$ using MILC's $N_f = 2+1+1$ HISQ ensembles at four lattice spacings, $a \approx 0.042, 0.06, 0.09$, and 0.12 fm, and various HISQ quark masses down to the (degenerate) physical light quark mass. We use the kinematic constraint $f_+(q^2)= f_0(q^2)$ at $q^2 = 0$ to determine the vector form factor from our study of the scalar current, which yields $f_0(0)$.
Results are extrapolated to the continuum physical point in the framework of hard pion/kaon SU(3) heavy-meson-staggered $\chi$PT and Symanzik effective theory. Our calculation improves upon the precision achieved in existing lattice-QCD calculations of the vector form factors at $q^2=0$. We show the values of the CKM matrix elements $|V_{cs}|$ and $|V_{cd}|$ that we would obtain using our preliminary results for the form factors together with recent experimental results, and discuss the implications of these values for the second row CKM unitarity.
DOI: https://doi.org/10.22323/1.334.0269
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.