1210.5185 (Ziwen Fu)

Lattice QCD calculation of $K^+ K^-$ scattering length    [PDF]

Ziwen Fu

We deliver ab initio calculation of s-wave $K^+K^-$ scattering length ($a_0^{K^+K^-}$) by L\"uscher's formula. In the "Asqtad" improved staggered dynamical fermion formulation, we measure $K^+K^-$ four-point correlation function by moving wall sources without gauge fixing, and find $a_0^{K^+K^-} = 0.456 \pm 0.272$ fm, which is in reasonable agreement with tree-level prediction and comparable with experimental result. An essential ingredient in our calculation is to explicitly include the disconnected diagram.

View original: http://arxiv.org/abs/1210.5185