Topology of three-jet events in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mrow><mml:mover><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi>¯</mml:mi></mml:mrow></mml:mover></mml:mrow></mml:mrow><mml:mi>p</mml:mi></mml:math>collisions at<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt></mml:mrow><mml:mrow><mml:mrow><mml:mrow/></mml:mrow></mml:mrow><mml:mo>=</mml:mo><mml:mn>1.8</mml:mn><mml:mn/></mml:math>TeV

The production and event topology of three-jet events produced in $p\overline{p}$ collisions at $\sqrt{s}=1.8$ TeV have been studied with the Collider Detector at Fermilab at the Tevatron Collider. The distributions of the three-jet angular variables (${\ensuremath{\psi}}^{*}$ and $cos{\ensuremath{\theta}}^{*}$) 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.