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arXiv · hep-lat/0209124

I=2 Pion Scattering Phase Shift with Wilson Fermions

PACS Collaboration·S. Aoki·M. Fukugita·S. Hashimoto·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneko·Y. Kuramashi·V. Lesk·M. Okawa·Y. Taniguchi·A. Ukawa·T. Yoshié
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Abstract

We present a lattice QCD calculation of the scattering phase shift for the I=2 $S$-wave two-pion system using the finite size method proposed by Lüscher. We work in the quenched approximation employing the standard plaquette action at $β=5.9$ for gluons and the Wilson fermion action for quarks. The phase shift is extracted from the energy eigenvalues of the two-pion system, which are obtained by a diagonalization of the pion 4-point function evaluated for a set of relative spatial momenta. In order to change momentum of the two-pion system, calculations are carried out on $24^3\times 60$, $32^3\times 60$, and $48^3\times 60$ lattices. The phase shift is successfully calculated over the momentum range $0 < p^2 < 0.3 {\rm GeV}^2$.

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PACS Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, V. Lesk, M. Okawa, Y. Taniguchi, A. Ukawa, T. Yoshié. 2002-11-05. I=2 Pion Scattering Phase Shift with Wilson Fermions. https://doi.org/10.1103/physrevd.67.014502

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