2014/10/30 by N. Ishizuka, Ishizuka, N., Ken-Ichi Ishikawa +5
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.1410.8237
openalex publication_date 2014/10/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present results for the K→ππ decay amplitudes for both the ΔI=1/2 and 3/2 channels. This calculation is carried out on 480 gauge configurations in Nf=2+1 QCD generated over 12,000 trajectories with the Iwasaki gauge action and non-perturbatively O(a)-improved Wilson fermion action at a=0.091 \rm fm, mπ=280 \rm MeV and mK=580 \rm MeV on a 323× 64 (La=2.9 \rm fm) lattice. For the quark loops in the Penguin and disconnected contributions in the I=0 channel, the combined hopping parameter expansion and truncated solver techniques work very well for variance reduction. We obtain, for the first time with a Wilson-type fermion action, that \rm ReA0 = 60(36) ×10 -8 \rm GeV and \rm ImA0 =-67(56) ×10-12 \rm GeV for a matching scale q^* =1/a. The dependence on the matching scale is weak.