Stealth gluons at hadron colliders

Roberto Barcelo; Adrian Carmona; Manuel Masip; Jose Santiago

doi:10.1016/j.physletb.2011.12.002

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arXiv · 1106.4054

Stealth gluons at hadron colliders

Roberto Barcelo·Adrian Carmona·Manuel Masip·Jose Santiago

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Abstract

We find that a heavy gluon G of mass 800-900 GeV with small, mostly axial-vector couplings to the light quarks and relatively large vector and axial-vector couplings to the top quark can explain the t \bar{t} forward-backward asymmetry observed at the Tevatron with no conflict with other top-quark or dijet data. The key ingredient is a complete treatment of energy-dependent width effects and a new decay mode G->qQ, where q is a standard quark and Q a vector-like quark of mass 400--600 GeV. We show that this new decay channel makes the heavy gluon invisible in the t\bar{t} mass invariant distribution and discuss its implications at the Tevatron and the LHC.

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Roberto Barcelo, Adrian Carmona, Manuel Masip, Jose Santiago. 2011-06-20. Stealth gluons at hadron colliders. https://doi.org/10.1016/j.physletb.2011.12.002

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