Energy and Color Flow in Dijet Rapidity Gaps

Abstract

When rapidity gaps in high-$p_T$ dijet events are identified by energy flow in the central region, they may be calculated from factorized cross sections in perturbative QCD, up to corrections that behave as inverse powers of the central region energy. Although power-suppressed corrections may be important, a perturbative calculation of dijet rapidity gaps in ${\rm p}\bar{\rm p}$ scattering successfully reproduces the overall features observed at the Tevatron. In this formulation, the average color content of the hard scattering is well-defined. We find that hard dijet rapidity gaps in quark-antiquark scattering are not due to singlet exchange alone.

Figures (2)

• Figure 1: Geometry of the calorimeter detector. $Q_c$ is the energy flow into the central rapidity interval
• Figure 2: The cross section (solid line) and the contributions from quasi-octet (dotted line) and quasi-singlet (dashed line), for $\sqrt{S}=630$ GeV, $\Delta y=3.2$, and $\sqrt{S}=1800$ GeV, $\Delta y=4.0$, respectively. Compare Fig. 1 of Ref. D0fig. Units are arbitrary.