The 34th International Symposium on Lattice Field Theory (Lattice 2016)

Leptonic decay-constant ratio fK/fπ from clover-improved Nf=2+1 QCD

28 Jul 2016, 14:40

20m

Building 67 Room 1003 (Highfield Campus, University of Southampton)

Talk Weak Decays and Matrix Elements Weak Decays and Matrix Elements

Speaker

Dr Enno E. Scholz (University of Regensburg)

Description

The leptonic decay-constant ratio $f_K/f_{\pi }$ is calculated from lattice-QCD simulations using $N_f=2+1$ dynamical fermion flavors in the clover-improved formulation and 2-HEX smearing. The simulations were performed at a range of mass-degenerate light quarks including the physical point and at various lattice couplings and volumes, allowing to quantify all relevant sources of systematic uncertainties for our final number of the decay-constant ratio. Utilizing input from ChPT, we also quote the charged decay-constant ratio $f_{K^{\pm }}/f_{{\pi }^{\pm }}$. With further input from super-allowed nuclear $\beta$-decays, eventually we obtain an estimate for the CKM-matrix element $V_{\mathrm{u}\mathrm{s}}$.

Presentation materials

Slides

lattice16_scholz.pdf