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arXiv · hep-ph/9507390

Disoriented Chiral Condensates: A Dynamical Simulation in the (2+1)-Dimensional Gross-Neveu Model

Abstract

We simulate the formation and growth of disoriented chiral condensate (DCC) regions which follow the expansion of a high energy density region into the ``cold'' vacuum. The numerical study is based on the one-loop effective potential for the massive 2+1-dimensional Gross-Neveu model. We pay attention to the setting of the initial conditions and to determining which parameters are relevant for a strong amplification of the pion field. We find that the size of the ``hot'' source plays a significant role. For large enough source radii, we observe strong correlation phenomena, corresponding to the growth of large regions where the pion field oscillates along a given direction. We give our results in terms of the $θ$ angle which defines the DCC disorientation, of the other $O(4)$ angles distributions, of the local ratios $R_{a}=π_{a}^{2}/{\vecπ}^2$ $(a=1,2,3)$, and of the energies associated with the fields at representative times.

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BibTeXRIS

A. Barducci, L. Caiani, R. Casalbuoni, R. Gatto, M. Modugno, G. Pettini. 1995-07-24. Disoriented Chiral Condensates: A Dynamical Simulation in the (2+1)-Dimensional Gross-Neveu Model. https://doi.org/10.1016/0370-2693(95)01521-3

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