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Implications of the CDF \( t\bar{t} \) forward-backward asymmetry for hard top physics

  • Cédric Delaunay
  • Oram Gedalia
  • Yonit Hochberg
  • Gilad Perez
  • Yotam Soreq
Article

Abstract

The CDF collaboration has recently reported a large deviation from the standard model of the \( t\bar{t} \) forward-backward asymmetry in the high invariant mass region. We interpret this measurement as coming from new physics at a heavy scale Λ, and perform a model-independent analysis up to \( \mathcal{O}\left( {{{1} \left/ {{{\Lambda^4}}} \right.}} \right) \). A simple formalism to test and constrain models of new physics is provided. We find that a large asymmetry cannot be accommodated by heavy new physics that does not interfere with the standard model. We show that a smoking gun test for the heavy new physics hypothesis is a significant deviation from the standard model prediction for the \( t\bar{t} \) differential cross section at large invariant mass. At \( {M_{t\bar{t}}} > 1\;{\text{TeV}} \) the cross section is predicted to be at least twice that of the SM at the Tevatron, and for \( {M_{t\bar{t}}} > 1.5\;{\text{TeV}} \) at least three times larger than the SM at the LHC.

Keywords

Phenomenological Models 

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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  • Cédric Delaunay
    • 1
  • Oram Gedalia
    • 1
  • Yonit Hochberg
    • 1
  • Gilad Perez
    • 1
  • Yotam Soreq
    • 1
  1. 1.Department of Particle Physics and AstrophysicsWeizmann Institute of ScienceRehovotIsrael

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