How to tell quark jets from gluon jets

A method to distinguish between light-quark jets and gluon jets in a calorimeter detector is presented. The method could be used to refine the experimental test of QCD based on the single-jet cross section, by comparing the quark and gluon contributions separately. It could also be used to enhance the signal/background ratio in searching for the top quark in ${\mathit{W}}^{\pm }$+jets channels. Optimistically, it might even make it possible to observe the hadronic decays ${\mathit{W}}^{\pm }$→jj and ${\mathit{Z}}^0$→jj, which would allow the W and Z masses to be used as benchmarks for calibrating the calorimeter, and perhaps even provide a useful measurement of ${\mathit{M}}_{\mathit{W}}$/${\mathit{M}}_{\mathit{Z}}$. The method has been developed using Monte Carlo simulations of jet events. Ways to compare it with experiment are discussed. The comparison would provide an important test for QCD shower simulation models.