Topology of three-jet events in $\overline{p}p$ collisions at $\sqrt{s}=1.8\mathrm{}$ TeV

The production and event topology of three-jet events produced in $p\overline{p}$ collisions at $\sqrt{s}=1.8\mathrm{}$ TeV have been studied with the Collider Detector at Fermilab at the Tevatron Collider. The distributions of the three-jet angular variables (${\psi }^{*}$ and $cos{\theta }^{*}$) and of the variables describing the energy sharing between jets ($x_3$ and $x_4$) are found to agree well with tree-level QCD calculations. These distributions are predicted to have different shapes for different initial-state subprocesses (quark-antiquark, quark-gluon, and gluon-gluon). The data are consistent with the small expected contribution from quark-antiquark initial states, in agreement with theoretical expectations.