Decay Chains


  1. Johan Alwall
  2. Tim Stelzer

Aim of the project

Allow MadGraph to specify decay chains of the type pp>(t>(W+>e+ve)b)(t~>(W->jj)b~).



  • MadGraph:
    • Implementation of pruning of topologies to speed up process generation for many final state particles
    • Example: pp>(t>(w+>jj)b)(t~>(w->l-vl~)b~): 16 min 15 s with decay chains, 2 h 33 min without decay chains
    • Allow only specified decay chains. Give information on which resonances must be on-shell to MadEvent
    • Allow more than 9 external particles
  • MadEvent:
    • Read on-shell resonance information to generate only correct diagrams
    • Allow more than 9 external particles

The implementation in MadGraph and MadEvent is completed, but needs to be tested with "real" physics. Still to do is:

  • Diagram drawing for more than 9 external particles
  • Allowing more than 10 external particles in MadGraph

Physics results and papers writeup

To be decided

-- Main.JohanAlwall - 31 Aug 2007

Last modified 7 years ago Last modified on 04/06/12 16:33:02