== SM + new DY resonances ==
We consider new spin-0, 1, and 2 resonances that can contribute to the s-channel Drell-Yan processes p,p->l+,l-,X and p,p->l,v,X where l is a charged lepton, v is a neutrino or antineutrino and X is the inclusive hadronic remnants. We implement the most general Lagrangian between these new bosons and the SM fermions and gluons allowed by Lorentz, quantum chromodynamic and electromagnetic invariance. In each case, we only include the leading effective terms which are either dimension-4 or dimension-5 operators. Furthermore, we drop all terms which vanish when the masses of the initial-state and final-state particles are taken to zero. Further details can be found in the reference below.
=== Implementation Author ===
* Neil Christensen
* University of Wisconsin - Madison
* neil -at- hep.wisc.edu
in collaboration with Cheng-Wei Chiang, Gui-Jun Ding, and Tao Han.
=== References ===
* [http://arxiv.org/abs/1107.5830 arXiv:1107.5830]
=== Model Files ===
* [/raw-attachment/wiki/DY-SM/DY-SM-FR.tgz DY-SM-FR.tgz]: [http://feynrules.irmp.ucl.ac.be/ FeynRules] Model Files
=== Model Implementation ===
Details about this implementation can be found in the reference above. Additionally, the [http://feynrules.irmp.ucl.ac.be/ FeynRules] automatic output for this model can be found here:
* [/attachment/wiki/DY-SM/DY-SM.pdf DY-SM.pdf]: Fields, parameters, Lagrangians and Vertices.
=== Instructions ===
We provide a basic notebook giving examples of how to run the [http://feynrules.irmp.ucl.ac.be/ FeynRules] interfaces on this model. Before running the notebook, the user must change $!FeynRulesPath to the path of FeynRules on their computer and the user must change $!ModelDir to the path to the DY-SM FeynRules model files downloaded from here:
* [/raw-attachment/wiki/DY-SM/SMplus.nb.gz SMplus.nb.gz]
After loading the model in CalcHEP or !MadGraph, suppose you want to run a Z' with SM-like couplings. The Z' name is VV, the mass is MVV, the width is WVV and you would set the couplings as:
* gVuR11=0.1861*(1-8/3*0.23369)
* gAuR11=0.1861*(-1)
* gVuR22=0.1861*(1-8/3*0.23369)
* gAuR22=0.1861*(-1)
* gVdR11=0.1861*(-1+4/3*0.23369)
* gAdR11=0.1861*(1)
* gVdR22=0.1861*(-1+4/3*0.23369)
* gAdR22=0.1861*(1)
* gVlR11=0.1861*(-1+4*0.23369)
* gAlR11=0.1861*(1)
* gVlR22=0.1861*(-1+4*0.23369)
* gAlR22=0.1861*(1)
You may also want to run a W' with SM-like couplings. The W' names are VVP+ and VVP-, the width is WVVP and you would set the couplings as:
* hVqR11=0.231*cos(0.227736)
* hAqR11=-0.231*cos(0.227736)
* hVqR12=0.231*sin(0.227736)
* hAqR12=-0.231*sin(0.227736)
* hVqR21=-0.231*sin(0.227736)
* hAqR21=0.231*sin(0.227736)
* hVqR22=0.231*cos(0.227736)
* hAqR22=-0.231*cos(0.227736)
* hVlR11=0.231
* hAlR11=-0.231
* hVlR22=0.231
* hAlR22=-0.231
=== Interfaces ===
This model implementation is known to work with [http://theory.sinp.msu.ru/~pukhov/calchep.html CalcHEP]. The CalcHEP files can be found here:
* [/raw-attachment/wiki/DY-SM/SM-DY-CH.tgz SM-DY-CH.tgz]
This model also runs with [http://madgraph.hep.uiuc.edu/ MadGraph 5] but has not been as thoroughly tested. The files can be found here:
* [/raw-attachment/wiki/DY-SM/dy_sm_fr.tgz dy_sm_fr.tgz]
Please report any bugs to Neil Christensen.
=== Validation ===
The Feynman rules were computed by hand and compared with the [http://feynrules.irmp.ucl.ac.be/ FeynRules] vertices and found to agree. Furthermore, the squared amplitudes for several Drell-Yan processes were calculated by hand and compared with the analytic output of CalcHEP and found to agree. Hermiticity of the Lagrangian was also tested at the Feynman rules level.