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arXiv · 0808.3372

Beyond the rainbow: effects from pion back-coupling

Christian S. Fischer·Richard Williams
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Abstract

We investigate hadronic unquenching effects in light quarks and mesons. To this end we take into account the back-coupling of the pion onto the quark propagator within the non-perturbative continuum framework of Schwinger-Dyson equations (SDE) and Bethe-Salpeter equations (BSE). We improve on a previous approach by explicitly solving both the coupled system of DSEs and BSEs in the complex plane and the normalisation problem for Bethe-Salpeter kernels depending on the total momentum of the meson. As a result of our study we find considerable unquenching effects in the spectrum of light pseudoscalar, vector and axial-vector mesons.

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Christian S. Fischer, Richard Williams. 2008-09-30. Beyond the rainbow: effects from pion back-coupling. https://doi.org/10.1103/physrevd.78.074006

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