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Non-Equilibrium Production of Photons via π^0\to 2γin DCC's

D. Boyanovsky·H. J. de Vega·R. Holman·S. Prem Kumar
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Abstract

We study production of photons via the non-equilibrium relaxation of a Disoriented Chiral Condensate with the chiral order parameter having a large initial amplitude along the π^0 direction. Assuming the validity of the low energy coupling of the neutral pion to photons via the U_A(1) anomalous vertex, we find that for large initial amplitudes along the π^0 direction, photon production is enhanced by parametric amplification. These processes are non-perturbative with a large contribution during the non-equilibrium stages of the evolution and result in a distinct distribution of the produced photons and a polarization asymmetry. For initial amplitudes of the π^0 component of the order parameter between 200-400 MeV, corresponding to energy densities between 1-12 GeV/fm^3 we find a peak in the photon distribution at energies between \approx 300 -600 MeV. We also find polarization asymmetries typically between 5-10%. We discuss the potential experimental impact of these results as well as the problems associated with its detection.

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D. Boyanovsky, H. J. de Vega, R. Holman, S. Prem Kumar. 1997-03-26. Non-Equilibrium Production of Photons via π^0\to 2γin DCC's. https://doi.org/10.1103/physrevd.56.3929

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