The Balitsky-Kovchegov (BK) evolution equation describes the energy evolution of gluon distribution functions allowing thus the study various processes at very high energies beyond the energy range of current experiments at the Large Hadron Collider. Such an equation is frequently combined in the literature with the high-energy eikonal approximation for the nuclear dipole amplitude. This leads to a significant overestimation of coherence effects in model predictions due to long lifetimes of all photon fluctuations exceeding considerably the size of the nuclear medium. For this reason, a non-trivial modification of the BK equation is required for a proper inclusion of shadowing effects allowing so its following application to various processes on nuclear targets. Besides, a correct incorporation of shadowing effects into the BK equation might have a huge impact for a conclusive evidence of saturation effects in reactions on nuclear targets.
Proposed dissertation topic covers an unique, non-trivial and proper incorporation of quantum coherence effects into the BK equation using path integral technique with a subsequent application of such an equation to various processes on nuclear targets.
Tasks:
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Revolutionary and original modification of the Balitsky-Kovchegov evolution equation with a proper incorporation of quantum coherence effects for particular Fock states of the photon,
- Calculations of nuclear cross sections for various processes on nuclear targets within the color dipole formalism,
- Comparison of model calculations with available data on electroproduction of heavy quarkonia off nuclei, nuclear modification of proton struction functions, etc.,
- Predictions for future experiments on the planned Large Hadron-Electron Collider,
- Comparison of our new results with standard calculations based on combination of the BK equation with the eikonal approximation for the nuclear dipole amplitude,
- Searching for a possible evidence of saturation effects in reactions on nuclear targets.
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