Version 21 (modified by donini, 7 years ago) (diff)


W' Effective model

Author Benjamin Fuks

  • IPHC Strasbourg / University of Strasbourg
  • fuks@…

Description of the model

This model is an extension of the SM, including additional interaction of fermions to a W' boson following the lowest-order effective Lagrangian described in Refs. [1] [2]:

$\mathcal{L} = \frac{V'_{ij}}{2\sqrt{2}} \bar{f}_{i} \gamma_{\mu} \left( g'_{R_{i,j}} (1+\gamma^5 ) +g'_{L_{i,j}} (1-\gamma^5 ) \right) W'^{\mu} f_j + h.c.$

where g'R,L are the right-handed (left-handed) W'-boson gauge couplings to fermions fi and fj, and V'ij is either the CKM matrix or a diagonal matrix, for quarks and leptons respectively.

Model files

  • the main model file.
  • WEff.nb: example of Mathematica notebook that loads the model, calculates the Feynman rules and extract the model files within the UFO format.
  • weff.ufo.tgz: The model files in UFO format (for MadGraph? 5).


  • The W'-boson mass and width are set using the parameters MWp and WWp, respectively
  • The left-handed (right-handed) W'-boson couplings to quarks and leptons are given by the matrices CLq and CLl (CRq and CRl) respectively.
    By default CLq and CRq are set to the CKM values and CLl and CRl are set to identity.
  • The left-handed and right-handed W'-boson coupling constants are set by the parameters gL and gR.
    By default these values are set at 0.1.


[1] Z. Sullivan, Fully differential W production and decay at next-to-leading order in QCD, Phys. Rev. (2002) 075011, arXiv:hep-ph/0207290 [hep-ph].

[2] D. Duffty and Z. Sullivan, Model independent reach for W-prime bosons at the LHC, Phys. Rev. D86 (2012) 075018, arXiv:1208.4858 [hep-ph].

[3] This W' model was used for a search of W'->tb process at the LHC with the ATLAS detector: ATLAS-CONF-2013-050

Attachments (3)

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