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arXiv · hep-lat/9609015

Electromagnetic Splittings and Light Quark Masses

A. Duncan·E. Eichten·H. Thacker
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Abstract

A method for computing electromagnetic properties of hadrons in lattice QCD is described. The electromagnetic field is introduced dynamically, using a noncompact formulation. Employing enhanced electric charges, the dependence of the pseudoscalar meson mass on the (anti)quark charges and masses can be accurately calculated. At $β=5.7$ with Wilson action, the $π^+-π^0$ splitting is found to be $4.9(3)$ MeV. Using the measured $K^0-K^+$ splitting, we also find $m_u/m_d = .512(6)$. Systematic errors are discussed. Preliminary results for vector meson splittings are also presented.}

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A. Duncan, E. Eichten, H. Thacker. 1996-09-05. Electromagnetic Splittings and Light Quark Masses. https://doi.org/10.1016/s0920-5632(96)00641-x

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