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arXiv · 1004.3449

A dispersion relation for the pion-mass dependence of hadron properties

Tim Ledwig·Vladimir Pascalutsa·Marc Vanderhaeghen
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Abstract

We present a dispersion relation in the pion-mass squared, which static quantities (nucleon mass, magnetic moment, etc.) obey under the assumption of analyticity in the entire complex $m_\pi^2$ plane modulo a cut at negative $m_\pi^2$ associated with pion production. The relation is verified here in a number of examples of nucleon and $\Delta$-isobar properties computed in chiral perturbation theory up to order $p^3$. We outline a method to obtain relations for other mass-dependencies, and illustrate it on a two-loop example.

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Tim Ledwig, Vladimir Pascalutsa, Marc Vanderhaeghen. 2010-04-20. A dispersion relation for the pion-mass dependence of hadron properties. https://doi.org/10.1016/j.physletb.2010.05.023

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