ef="SemiInternalProcesses.html" target="page">semi-internal</a> processes,
meaning they are handled identically with normal internal ones.
This way, MadGraph 5 can be used to implement processes from 
any model that can be written in  terms of a Lagrangian. Any 
<i>2 -> 1</i>, <i>2 -> 2</i> and <i>2 -> 3</i> processes 
can be implemented, the limit being set by the absence of efficient
phase space generator algorithms for higher multiplicities in
PYTHIA. Features such as <i>s</i>-channel resonances are
auto