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Probing color coherence effects in pp collisions at [Formula: see text]
, S Chatrchyan1, V Khachatryan1
1Yerevan Physics Institute, Yerevan, Armenia.
The European Physical Journal. C, Particles and Fields
|March 28, 2015
Summary
Researchers studied color coherence effects in proton-proton collisions at the Large Hadron Collider. Current models fail to accurately describe the observed angular correlations between jets, indicating a need for improved theoretical understanding.
Area of Science:
- High Energy Physics
- Quantum Chromodynamics
- Particle Physics
Background:
- Color coherence is a fundamental concept in Quantum Chromodynamics (QCD).
- Understanding these effects is crucial for interpreting particle collision data.
- Previous studies have explored coherence in various collision systems.
Purpose of the Study:
- To investigate color coherence effects in proton-proton (pp) collisions.
- To measure the angular correlation between the second- and third-leading jets.
- To compare experimental data with predictions from various Monte Carlo models.
Main Methods:
- Analysis of pp collision data collected by the CMS detector at the LHC.
- Selection of events with at least three jets and a back-to-back topology for the two leading jets.
- Measurement of the angular correlation between the second- and third-leading jets.
Main Results:
- The measured angular correlation is sensitive to color coherence.
- A significant discrepancy was observed between the data and predictions from all tested Monte Carlo models.
- None of the models satisfactorily described the experimental results.
Conclusions:
- The study highlights limitations in current theoretical models of color coherence.
- Further refinement of Monte Carlo simulations is required to accurately describe experimental observations.
- This research provides valuable data for advancing the understanding of QCD phenomena.
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