'''The B-L model'''
 as a U(1) extension of the SM with 3 RH neutrinos and a singlet scalar.

This is an update to the previous minimal Zprime model.

** Implementation authors

* This version
 * Wei Liu
  * Department of Physics & Astronomy, University College London
  * wei.liu.16 -at- ucl.ac.uk
  * update based on Lorenzo Basso's model with availability to FeynRules 2.3.

* Previous version
 * Lorenzo Basso
  * Physikalisches Institut, Albert-Ludwigs-Universität Freiburg (Germany)
  * lorenzo.basso -at- physik.uni-freiburg.de
  * (formerly at University of Southampton, UK & RAL-PPD, Didcot, UK)
  * Based upon the minimal B-L model implementation, done in collaboration with Giovanni Marco Pruna (TU Dresden, Institut für Kern- und Teilchenphysik, Dresden, Germany, formerly at University of Southampton, UK & RAL-PPD, Didcot, UK).



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** Model description

The model describe a U(1) extension of the SM, related to the B-L (baryon minus lepton) charge. 3 RH neutrinos are required to cancel the anomalies, thus providing neutrino masses via the type-I see-saw. A Z' boson is also present, together with a further scalar for the spontaneous symmetry breaking of the further U(1) factor, at TeV scale.


 - Minimal B-L model: gt = 0. This is the "Minimal" version of the model, where the mixing between Z and Z' is set to zero. This choice is set for the .fr and UFO file.
 {{{#!comment

This model describes a 1-dimensional class of Z' models, where a continuous parameter scans over the possible discrete models. The model is fully implemented in the Feynman gauge (also Goldstones and Ghosts).

Popular benchmark models from the literature are recovered by setting appropriated relations among the new gauge parameters.
Separate model files for this benchmark model exists.
- SO(10)-inspired U(1)_chi: gt = - 4/5 g1p.
 - U(1)_R: gt = -2 g1p.
}}}

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** References
* Please cite https://arxiv.org/abs/1811.11452 and http://arxiv.org/abs/arXiv:0812.4313 for the using this version of the model.
* This version
 * https://arxiv.org/abs/1811.11452 LHC Constraints on a