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arXiv · 0910.2658

Two pion scattering, I=0 and disconnected diagrams in Lattice QCD

Qi Liu
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Abstract

A full, high-statistic I=0 and I=2 $π-π$ scattering calculation including the disconnected diagram is performed on 2+1 flavor, domain wall fermion gauge configurations generated using the Iwasaki gauge action with $β=2.13$, a $16^3\times32$ volume with $L_s=16$ and $a^{-1}=1.73GeV$. Using the same light quark propagators and additional strange quark propagators, we study the $η$ and $η^\prime$ mesons, where disconnected diagrams also make an important contribution. Our $π-π$ calculation shows a good exponentially decaying signal from the disconnected graph, which makes a small contribution to the I=0 scattering amplitude at least for the short times where it can be accurately computed. We are able to resolve the $η$ and $η^\prime$ states and see the pattern of SU(3) flavor symmetry breaking found in Nature.

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Qi Liu. 2009-10-14. Two pion scattering, I=0 and disconnected diagrams in Lattice QCD. https://arxiv.org/abs/0910.2658

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