QCD under magnetic field: chiral magnetic effect at heavy ion collisions
Chung Kao2010, arXiv (Cornell University)
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Abstract
In this talk, we report our recent studies for the chiral magnetic effect, which signals the P -and CP -violations at heavy ion collisions. We compute the electric current and its correlations, induced by the external magnetic field, inside the hot and dense QCD matter created in the HIC. For this purpose, we employ the instanton-liquid model, modified by the Harrington-Shepard caloron at finite T . We observe that the chiral magnetic effect current and its correlations increase with respect to the magnetic field, whereas decease as functions of T , due to the diluting instanton ensemble. It turns out that the numerical results are in good agreement with those from the model-independent analyses and lattice QCD simulations. We also reproduce the charge separations, observed in the STAR experiment, qualitatively well, considering the simplified Liénard-Wiechert potential, screening and size effects.
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