== 3-jet production at the Tevatron ==

Use MadGraph/MadEvent to obtain the distributions of %$x_3,x_4$% where %$x_i=2 E_i/M_{3j}$% are the energy fraction of the jets normalized as %$x_3+x_4+x_5=2$%, with %$x_3>x_4>x_5$%, in three-jet events. Consider %$p\bar p$% collisions at 1.8 TeV of c.m.s. Set the minimum %$p_T$% for the jets to 15 GeV, the maximum rapidity of %$3.5$% and the %$\Delta R=0.8$%. Compare your results with the experimental data from CDF, Run I, shown in the Figure below.

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