class TPythia6Decayer: public TVirtualMCDecayer

 Get the singleton object.

 Constructor

 Initialize the decayer

 Decay a particle of type IDPART (PDG code) and momentum P.

 Get the decay products into the passed PARTICLES TClonesArray of
 TParticles

 Force a particular decay type

 Force a particle decay mode

 Get the partial branching ratio for a particle of type IPART (a
 PDG code).

 Get the life-time of a particle of type KF (a PDG code).

 Read in particle data from an ASCII file.   The file name must
 previously have been set using the member function
 SetDecayTableFile.

 write particle data to an ASCII file.   The file name must
 previously have been set using the member function
 SetDecayTableFile.

 Users can use this function to make an initial decay list file,
 which then can be edited by hand, and re-loaded into the decayer
 using ReadDecayTable.

 The file syntax is

    particle_list : partcle_data
                  | particle_list particle_data
                  ;
    particle_data : particle_info
                  | particle_info '\n' decay_list
                  ;
    particle_info : See below
                  ;
    decay_list    : decay_entry
                  | decay_list decay_entry
                  ;
    decay_entry   : See below

 The particle_info consists of 13 fields:

     PDG code             int
     Name                 string
     Anti-particle name   string  if there's no anti-particle,
                                  then this field must be the
                                  empty string
     Electic charge       int     in units of |e|/3
     Color charge         int     in units of quark color charges
     Have anti-particle   int     1 of there's an anti-particle
                                  to this particle, or 0
                                  otherwise
     Mass                 float   in units of GeV
     Resonance width      float
     Max broadning        float
     Lifetime             float
     MWID                 int     ??? (some sort of flag)
     Decay                int     1 if it decays. 0 otherwise

 The format to write these entries in are

    " %9  %-16s  %-16s%3d%3d%3d%12.5f%12.5f%12.5f%13.gf%3d%d\n"

 The decay_entry consists of 8 fields:

     On/Off               int     1 for on, -1 for off
     Matrix element type  int
     Branching ratio      float
     Product 1            int     PDG code of decay product 1
     Product 2            int     PDG code of decay product 2
     Product 3            int     PDG code of decay product 3
     Product 4            int     PDG code of decay product 4
     Product 5            int     PDG code of decay product 5

 The format for these lines are

    "          %5d%5d%12.5f%10d%10d%10d%10d%10d\n"

 Count number of decay products

 Force golden D decay modes

  Force decay of particle into products with multiplicity mult

  Force decay of particle into products with multiplicity mult

 Force Omega -> Lambda K- Decay