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arXiv · 0710.0869

Lattice Results for Vector Meson Couplings and Parton Distribution Amplitudes

D. Antonio·P. A. Boyle·M. A. Donnellan·J. Flynn·A. Juttner·C. Maynard·B. Pendleton·C. T. Sachrajda·R. Tweedie
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Abstract

We present results for the couplings of light vector mesons to vector and tensor currents and on the low moments of the light-cone distribution amplitudes of the pion and kaon. The calculations are performed on the RBC and UKQCD collaborations' ensembles generated with the Iwasaki gauge action and with 2+1 flavours of domain wall fermions. The (preliminary) results for the ratios of the couplings of the vector meson to the vector and tensor currents (f_V and f^T_V respectively) in the MSbar scheme at 2GeV are: f_ρ^T/f_ρ=0.681(20); f_{K^\ast}^T/f_{K^\ast}=0.712(11) and f_ϕ^T/f_ϕ=0.751(9). For the first moment of the kaon's distribution amplitude we find (in the same scheme and at the same scale) _K=0.029(2) and for the second moment _π=0.28(3) and _K=0.27(2).

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D. Antonio, P. A. Boyle, M. A. Donnellan, J. Flynn, A. Juttner, C. Maynard, B. Pendleton, C. T. Sachrajda, R. Tweedie. 2007-10-03. Lattice Results for Vector Meson Couplings and Parton Distribution Amplitudes. https://arxiv.org/abs/0710.0869

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