Decay Chains

People

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~).

Tools

• MadGraph

Work

• 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