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PYTHIA 6.205 is used for final state QED and /QCD parton showering and for the fragmentation of quarks and gluons. Parton showering is done for all final state ferminons with the exception of electrons. Final state QED showering of electrons
is turned off because the PYTHIA final state showering code indiscriminately uses the invariant mass of
final state fermion-antifermion pairs for the maximum virtuality scale.
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