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High-enegy effective action from scattering of QCD shock waves

Ian Balitsky
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Abstract

At high energies, the relevant degrees of freedom are Wilson lines - infinite gauge links ordered along straight lines collinear to the velocities of colliding particles. The effective action for these Wilson lines is determined by the scattering of QCD shock waves. I develop the symmetric expansion of the effective action in powers of strength of one of the shock waves and calculate the leading term of the series. The corresponding first-order effective action, symmetric with respect to projectile and target, includes both up and down fan diagrams and pomeron loops.

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Ian Balitsky. 2005-07-20. High-enegy effective action from scattering of QCD shock waves. https://doi.org/10.1103/physrevd.72.074027

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