Changes between Version 16 and Version 17 of VLQ

Timestamp:

Jun 24, 2013, 8:40:48 PM (11 years ago)

Author:

Mathieu Buchkremer

Comment:

--

VLQ

@@ -40 +40 @@
 
 
-All the above parameter classes are combined internally in the FeynRules model file [attachment:VLQ.fr] to match the model-independent prescription presented above [1]. The default parameter cards use the standard MadGraph  values for the SM input parameters, as given in [attachment:Parameters.pdf]. For consistency, all light quarks included in the proton definition are restricted to be massless (5F scheme) using the restriction file [attachment:Massless.rst] when loading the FeynRules model, except for the top, bottom and tau lepton masses. The default model loads the real 3X3 CKM matrix given in [attachment:Parameters.pdf] [2] as an external parameter. In general, the presence of new top partners induce model-dependent corrections to the mixings between the novel heavy fermions and the lighter quark families, and the SM electroweak couplings must be modified accordingly.
+All the above parameter classes are combined internally in the FeynRules model file [attachment:VLQ.fr] to match the model-independent prescription presented above [1]. The default parameter cards use the standard MadGraph  values for the SM input parameters, as given in [attachment:Parameters.pdf]. The default configuration assumes a vector-like T singlet, mixing exclusively with the third generation. For consistency, all light quarks included in the proton definition are restricted to be massless (5F scheme) using the restriction file [attachment:Massless.rst] when loading the FeynRules model, except for the top, bottom and tau lepton masses. The default model loads the real 3X3 CKM matrix given in [attachment:Parameters.pdf] [2] as an external parameter. In general, the presence of new top partners induce model-dependent corrections to the mixings between the novel heavy fermions and the lighter quark families, and the SM electroweak couplings must be modified accordingly.
 
 '''Extension''': In addition to the above parameterisation, an extension including chromomagnetic couplings between VL and Standard Model quarks is provided in the file VLQ_Chromomagnetic.fr. The new couplings (typically generated at loop level in minimal SM extensions) are implemented in terms of the dimension 6 operator: 
@@ -62 +62 @@
 Below we provide the tarballs containing the main model files and outputs. The model implementation is also known to work with the CalcHEP/CompHEP interfaces, which can be generated from the [attachment:VLQ.nb] Mathematica notebook. Although FeynRules now supports exclusively the version 5 of MadGraph (UFO format, in the unitary gauge), the MadGraph4 model files can be provided on demand.
 
-To import the model into MadGraph, it is enough to untar the UFO directory into the models subdirectory of MadGraph, and load the model using the "import model VLQ_UFO" command.
+To import the model into MadGraph, it is enough to untar the UFO directory into the models subdirectory of MadGraph, and load the model using the "import model VLQ_UFO" command. Note : by default, the model files assume a vector-like T singlet mixing exclusively with the third generation, as described in [attachment:Parameters.pdf].  
 
  * [attachment:VLQ.fr] : FeynRules main file.