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arXiv · hep-ph/9511273

Lower Bound on the Pion Polarizability from QCD Sum Rules

M. Benmerrouche·G. Orlandini·T. G. Steele
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Abstract

Making use of QCD sum rules a lower bound is found which relates the electromagnetic polarizability $α_{_E}$ and mean-square radius $\langle r_π^2\rangle$ of charged pions through the intrinsic polarizability $\tildeα_{_E}= α_{_E}-α\langle r_π^2\rangle/(3M_π)$. We find that if present constraints on the QCD continuum (duality) threshold are accepted, this lower bound on the intrinsic polarizability $\tildeα_{_E}$ is incompatible with some previous determinations of $α_{_E}$ and $\langle r_π^2\rangle$.

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M. Benmerrouche, G. Orlandini, T. G. Steele. 1995-11-08. Lower Bound on the Pion Polarizability from QCD Sum Rules. https://doi.org/10.1016/0370-2693(95)01386-5

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