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arXiv · 0811.2398

Chiral Partners and their Electromagnetic Radiation -- Ingredients for a systematic in-medium calculation

S. Leupold·M. F. M. Lutz·M. Wagner
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Abstract

It is argued that the chiral partners of the lowest-lying hadrons are hadronic molecules and not three-quark or quark-antiquark states, respectively. As an example the case of a_1 as the chiral partner of the rho is discussed. Deconfinement -- or as a precursor large in-medium widths for hadronic states -- is proposed as a natural way to accommodate for the fact that at chiral restoration the respective in-medium spectra of chiral partners must become degenerate. Ingredients for a systematic and self-consistent in-medium calculation are presented with special emphasis on vector-meson dominance which emerges from a recently proposed systematic counting scheme for the mesonic sector including pseudoscalar and vector mesons as active degrees of freedom.

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S. Leupold, M. F. M. Lutz, M. Wagner. 2008-11-14. Chiral Partners and their Electromagnetic Radiation -- Ingredients for a systematic in-medium calculation. https://doi.org/10.1016/j.ppnp.2008.12.042

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