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arXiv · 1109.0648

Very Light Axigluons and the Top Asymmetry

Gordan Z. Krnjaic
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Abstract

We show that very light (50 - 90 GeV) axigluons with flavor-universal couplings of order g_{s}/3 may explain the anomalous top forward-backward asymmetry reported by both CDF and D0 collaborations. The model is naturally consistent with the observed t \bar t invariant mass distribution and evades bounds from light Higgs searches, LEP event shapes, and hadronic observables at the Z pole. Very light axigluons can appear as resonances in multijet events, but searches require sensitivity to masses below current limits.

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Gordan Z. Krnjaic. 2011-09-03. Very Light Axigluons and the Top Asymmetry. https://doi.org/10.1103/physrevd.85.014030

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