0000000000814204
AUTHOR
Shoichi Sasaki
Accelerating Ab Initio Nucleon Structure Calculations with All-Mode-Averaging on Gordon
The composition of nucleons has long been known to be sub-atomic particles called quarks and gluons, which interact through the strong force and theoretically can be described by Quantum Chromodynamics (QCD). Lattice QCD (LQCD), in which the continuous space-time is translated into grid points on a four-dimensional lattice and ab initio Monte Carlo simulations are performed, is by far the only model-independent method to study QCD with controllable errors. We report the successful application of a novel algorithm, All-Mode-Averaging, in the LQCD calculations of nucleon internal structure on the Gordon supercomputer our award of roughly 6 million service units through XSEDE. The application …
Kl3Semileptonic Form Factor from (2+1)-Flavor Lattice QCD
We present the first results for the ${K}_{l3}$ form factor from simulations with $2+1$ flavors of dynamical domain wall quarks. Combining our result, namely, ${f}_{+}(0)=0.964(5)$ with the latest experimental results for ${K}_{l3}$ decays leads to $|{V}_{us}|=0.2249(14)$, reducing the uncertaintity in this important parameter. For the $O({p}^{6})$ term in the chiral expansion we obtain $\ensuremath{\Delta}f=\ensuremath{-}0.013(5)$.
Kl3form factor withNf= 2 +1 dynamical domain wall fermions
We present the latest results from the UKQCD/RBC collaborations for the Kl3 form factor from simulations with 2 + 1 flavours of dynamical domain wall quarks. Simulations are performed on lattices with two different volumes and four values of the light quark mass, allowing for an extrapolation to the chiral limit. The analysis includes a thorough investigation into the sources of systematic error in our fits. After interpolating to zero momentum transfer, we obtain f+(0) = 0.964(5) (or ?f = -0.013(5)) which, when combined with the latest experimental results for Kl3 decays, leads to |Vus| = 0.2249(14).