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arXiv · hep-lat/0702012

The Delta-resonance in a finite volume

Véronique Bernard·Ulf-G. Meißner·Akaki Rusetsky
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Abstract

We study the extraction of Delta-resonance parameters from lattice data for small quark masses, corresponding to the case of an unstable Delta. To this end, we calculate the spectrum of the correlator of two Delta-fields in a finite Euclidian box up-to-and-including O(epsilon^3) in the small scale expansion using infrared regularization. On the basis of our numerical study, we argue that the extraction of the parameters of the Delta-resonance (in particular, of the mass and the pion-nucleon-delta coupling constant) from the measured volume dependence of the lowest energy levels should be feasible.

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Véronique Bernard, Ulf-G. Meißner, Akaki Rusetsky. 2007-02-07. The Delta-resonance in a finite volume. https://doi.org/10.1016/j.nuclphysb.2007.07.030

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