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arXiv · 1011.5288

Resonance Parameters of the rho-Meson from Lattice QCD

Xu Feng·Karl Jansen·Dru B. Renner
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Abstract

We perform a non-perturbative lattice calculation of the P-wave pion-pion scattering phase in the rho-meson decay channel using two flavors of maximally twisted mass fermions at pion masses ranging from 480 MeV to 290 MeV. Making use of finite-size methods, we evaluate the pion-pion scattering phase in the center-of-mass frame and two moving frames. Applying an effective range formula, we find a good description of our results for the scattering phase as a function of the energy covering the resonance region. This allows us to extract the rho-meson mass and decay width and to study their quark mass dependence.

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Xu Feng, Karl Jansen, Dru B. Renner. 2010-11-24. Resonance Parameters of the rho-Meson from Lattice QCD. https://doi.org/10.1103/physrevd.83.094505

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