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arXiv · 1712.02093

Spectral Functions from the Functional Renormalization Group

Jochen Wambach·Christopher Jung·Fabian Rennecke·Ralf-Arno Tripolt·Lorenz von Smekal
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Abstract

We present results for in-medium spectral functions obtained within the Functional Renormalization Group framework. The analytic continuation from imaginary to real time is performed in a well-defined way on the level of the flow equations. Based on this recently developed method, results for the sigma and the pion spectral function for the quark-meson model are shown at finite temperature, finite quark-chemical potential and finite spatial momentum. It is shown how these spectral function become degenreate at high temperatures due to the restoration of chiral symmetry. In addition, results for vector- and axial-vector meson spectral functions are shown using a gauged linear sigma model with quarks. The degeneration of the $ρ$ and the $a_1$ spectral function as well as the behavior of their pole masses is discussed.

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Jochen Wambach, Christopher Jung, Fabian Rennecke, Ralf-Arno Tripolt, Lorenz von Smekal. 2017-12-06. Spectral Functions from the Functional Renormalization Group. https://arxiv.org/abs/1712.02093

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