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Journal of High Energy Physics

, 2016:127 | Cite as

Forward-backward asymmetry as a discovery tool for Z′ bosons at the LHC

  • Elena AccomandoEmail author
  • Alexander Belyaev
  • Juri Fiaschi
  • Ken Mimasu
  • Stefano Moretti
  • Claire Shepherd-Themistocleous
Open Access
Regular Article - Theoretical Physics

Abstract

The Forward-Backward Asymmetry (AFB) in Z′ physics is commonly only perceived as the observable which possibly allows one to interpret a Z′ signal appearing in the Drell-Yan channel by distinguishing different models of such (heavy) spin-1 bosons. In this paper, we revisit this issue, showing that the absence of any di-lepton rapidity cut, which is commonly used in the literature, can enhance the potential of the observable at the LHC. We moreover examine the ability of AFB in setting bounds on or even discovering a Z′ at the Large Hadron Collider (LHC) concluding that it may be a powerful tool for this purpose. We analyse two different scenarios: Z′-bosons with a narrow and wide width, respectively. We find that, in the first case, the significance of the AFB search can be comparable with that of the ‘bump’ search usually adopted by the experimental collaborations; however, in being a ratio of (differential) cross sections, the AFB has the advantage of reducing experimental systematics as well as theoretical errors due to PDF uncertainties. In the second case, the AFB search can outperform the bump search in terms of differential shape, meaning the AFB distribution may be better suited for new broad resonances than the event counting strategy usually adopted in such cases.

Keywords

Hadronic Colliders 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2016

Authors and Affiliations

  • Elena Accomando
    • 1
    Email author
  • Alexander Belyaev
    • 1
  • Juri Fiaschi
    • 1
  • Ken Mimasu
    • 2
  • Stefano Moretti
    • 1
  • Claire Shepherd-Themistocleous
    • 3
  1. 1.School of Physics and AstronomyUniversity of Southampton, Highfield CampusSouthamptonU.K.
  2. 2.School of Physics and AstronomyUniversity of SussexBrightonU.K.
  3. 3.Particle Physics Department, STFC, Rutherford Appleton LaboratoryOxfordshireU.K.

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