= The WHIZARD / O'Mega interface (C. Speckner) --- UNDER CONSTRUCTION =

== Overview ==
The WHIZARD / O'Mega interface generates the model files necessary for the inclusion of a FeynRules model into the WHIZARD / O'Mega framework. All versions of WHIZARD / O'Mega >= 1.92 are supported.

== Usage: all versions ==
As all other interfaces, the WO interface is invoked by calling {{{WriteWOOuput}}}. Three syntax variants are admissible:

1. {{{WriteWOOutput[Lagrangian, Options]}}}

2. {{{WriteWOOutput[{LagrangianList}, Options]}}}

3. {{{WriteWOOutput[Null, WOVertexList->{VertexList], Options]}}}

Version 1. operates on a single Lagrangian, while 2. operates on a list of Lagrangians and 3. takes a list of FeynmanRules as an argument. The following options are available:

 * {{{WOVertexList}}}: If {{{=!= Null}}}, this is interpreted as a list of Feynman rules and overrides any Lagrangian (or -list) specified (in this case, {{{Null}}} is accepted as first argument). Default: Null

 * {{{WOModelName}}}: The name by which the model will be identified in WO. Note that all models for W1.9x have to start with "fr" (e.g. {{{WOModelName->"fr_sm"}}}) if they are to be picked up by WO1.9x without user intervention (no such restriction exists for W2). Beware that the interface my modify this name if it doesn't fit into the WO naming schemes --- double check the generated messages to be sure. Default: derived from the FR model name

 * {{{WOMaxNcf}}}: Upper limit on the number of generated color flows which the generated code will be able to handle (essentially n_8 - n_3 / 2, where n_8 is the maximum number of external octets and n_3 that of external triplets). Irrelevant for W2; also, the technically experienced user can change this after generation in {{{f90_modellname_Col.ml}}}. Default: 4

 * {{{WOGauge}}}: The following gauges are available:
  * {{{WOUnitarity}}}: Unitarity gauge (default)
  * {{{WOFeynman}}}: Feynman gauge
  * {{{WORxi}}}: Rxi gauges. In this case, you __must__ define a parameter taking the role of \xi and pass it to the interface via {{{WOGaugeParameter}}} (see below).