Tracking fast small color dipoles through strong gluon fields at the LHC

Area of Science:

• High-energy particle physics
• Quantum Chromodynamics (QCD)
• Nuclear physics

Background:

• Understanding the interaction of small dipoles with nuclear media is crucial.
• A novel perturbative QCD regime of strong absorption is hypothesized.
• Experimental verification at collider energies is needed.

Purpose of the Study:

• To propose a method for testing the onset of strong absorption in a novel perturbative QCD regime.
• To investigate the interaction of small dipoles with nuclear media at high energies.
• To determine the feasibility of experimental studies at the LHC.

Main Methods:

• Analyzing the process gamma+A-->J/psi+"gap"+X at large momentum transfer (q^2).
• Utilizing data from the first heavy-ion run at the Large Hadron Collider (LHC).
• Employing ultraperipheral collisions for sufficient statistics.

Main Results:

• The proposed reaction serves as a quick and effective test.
• Sufficient statistics are achievable with the LHC's heavy-ion run.
• Probing of qq dipoles (size ~0.2 fm) down to x ~10^-5 is possible.

Conclusions:

• The gamma+A-->J/psi+"gap"+X process is a viable tool for exploring new QCD physics.
• The LHC is well-suited for these investigations.
• This research opens avenues for studying dipole-medium interactions.