2 5 76    Lagrangian                 
  This table contains interaction vertexes. The first four fields
(A1,A2,A3,A4) are the names of the interacting particles.  These fields
must contain particle names in CompHEP notation.  A4 may be empty.  The
last two fields 'Factor' and 'LorentzPart' define the vertex itself.  Let S
be the action, then
                    dS
-------------------------------------------------------------- = 1/(2* pi)^4
dA1(p1,[m1]) dA2(p2,[m2]) dA3(p3,[m3]) [dA4(p4,[m4])/(2*pi)^4]

*delta(p1+p2+p3 [+p4])*[gamma_0]*Color_Structure*Factor*LorentzPart

  Here 'p' and 'm' denote 4-momenta and  Lorentz indexes.  The brackets []
are used to mark the optional parts of the expression.  So terms containing
A4,p4,m4 appear for the case of four particle interaction vertex only. For
the case of anticommuting fields the RIGHT derivatives are assumed. The
gamma_0 term appears in a vertex with fermion fields.
 'Factor' must be a rational  monomial constructed from the model
identifiers, integer numbers and imaginary unit.
  The  'LorentzPart' must be  a tensor or  Dirac gamma-matrix expression.
Coefficients of this expression are polynomials of the model identifiers
and scalar products of momenta. To construct the scalar product we use the
dot "." symbol. The division '/' operation in the 'LorentzPart' is
forbidden. It must be moved to the 'Factor' field.
  To build a tensor expression  you can  construct the following
expressions by means of the dot product: m1.m2  -  the metric tensor;
p2.m4   -  momentum component.
  To build a Dirac gamma-matrix  with index 'm' we use symbol G(m). G(p)
denotes the Lorentz product of the gamma matrices with the 4-momentum.
The gamma_5 matrix  is denoted by G5.
  The 'ColorStructure' is substituted by CompHEP automatically. For a
colorless particle vertex it is equal to 1.  For (3x3-bar) and for
(8x8) vertex the Kroneker delta is substituted. If CompHEP meets vertex
with three particles in adjoint representation (8x8x8), it substitutes
           i*f(a1,a2,a3), 
where f represents a structure constant of SU(3). For  (3x3-barx8)  vertex
CompHEP substitutes the Gell-Mann lambda matrices
           lambda(i-bar,i,a)/2  
See Manual for details.
