Production of heavy quarks from<i>W</i>-gluon fusion

Abstract

We show that heavy-quark production via W-gluon fusion in high-energy pp and p\ifmmode\bar\else\textasciimacron\fi{}p collisions is an important source of the heavier member of an SU(2${)}_{\mathrm{L}}$ doublet of quarks if the mass splitting within the doublet is large. W-gluon fusion exceeds the strong production of heavy quarks for mass splittings greater than 300--350 GeV at \ensuremath{\surd}s =10 TeV and 400--450 GeV at \ensuremath{\surd}s =40 TeV. An alternative way to regard W-gluon fusion is as the production of the heavier quark by fusing its light partner with a W boson. We use a distribution function for the light partner to show that this process gives results which agree qualitatively with W-gluon fusion. We also discuss the Drell-Yan production of an SU(2${)}_{\mathrm{L}}$ doublet of heavy quarks via a virtual W boson and corrections to this process from initial gluons. We find that at the Fermilab Tevatron energy \ensuremath{\surd}s =2 TeV, W-gluon fusion exceeds the Drell-Yan production of top quarks for masses above 100 GeV.