Rapidity Gaps in Quark and Gluon Jets - a Perturbative Approach

TL;DR

This paper uses perturbative QCD to analyze rapidity gaps in quark and gluon jets, successfully describing experimental data and predicting how gap probabilities vary with jet resolution, highlighting a color blanching mechanism.

Contribution

It provides a perturbative QCD framework for understanding rapidity gaps in jets and predicts their behavior at different resolutions, connecting partonic and hadronic states.

Findings

Good description of e+e- annihilation data using MLLA calculations.

Predicted strong variation of gap probabilities at small y_{cut}.

Suggested a color blanching mechanism for large spatial separations.

Abstract

We derive the probability for rapidity gaps in a parton cascade and investigate the dual connection with hadronic final states. A good description of observations in e+e- annihilations is obtained by perturbative QCD calculations in MLLA using previously determined parameters (QCD scale \Lambda and k_T-cut-off Q_0) and applying the parton hadron duality picture. Further predictions are derived; especially, for gaps between jets at variable resolution we predict a strong variation of gap probabilities for small parameters y_{cut} -> 0 in the transition from jets to hadrons. Large gaps between partons correspond to large spatial separations of colour charges: a colour blanching mechanism by soft processes is suggested.