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arXiv · hep-ph/9601316

Anomalous mesonic interactions near a chiral phase transition

Robert D. Pisarski
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Abstract

Using constituent quarks coupled to a linear sigma model at nonzero temperature, I show that many anomalous mesonic amplitudes, such as $π^0 \rightarrow γγ$, vanish in a chirally symmetric phase. Processes which are allowed, such as $π^0 σ\rightarrow γγ$, are computed to leading order in a loop expansion.

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Robert D. Pisarski. 1996-01-23. Anomalous mesonic interactions near a chiral phase transition. https://doi.org/10.1103/physrevlett.76.3084

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