Single vectorlike quark production at the LHC

Abstract

A gluon resonance G of mass below 1 TeV could be the origin of the t t ¯ forward–backward asymmetry observed at the Tevatron provided that new decay modes G → q Q ¯ , with q a standard quark and Q its massive excitation, make G broad enough. We consider all the different cases, with q the top, the bottom or a light quark and dominant decay modes Q → W q ′ or Q → Z q . We show that current experimental searches are unable to probe the model, but that minimal departures from these analyses can explore a large region of its parameter space for the current LHC luminosity. This includes the challenging case with the new quarks decaying mostly into light quark flavors. In some channels not only the heavy quark but also the massive gluon can be reconstructed, which would stablish the origin of the t t ¯ asymmetry. Similar analyses can be applied to more general models with new massive gluons and vectorlike quarks.