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The massless assumption for the first and second fermion generations can produce some odd results given the kinematic cut values we have chosen. For example, the cross section for gamma gamma -> tau tau is significantly larger than the cross section for gamma gamma -> mu mu since the cut value of 4 GeV for default_mass_cut and default_q_cut is much larger than the tau mass.
Also the cross section for gamma gamma -> qq is suppressed relative to the corresponding cross section for lepton pair
production because the cut value of 10 GeV for default_jet_cut is larger than the cut value of 4 GeV for default_mass_cut .
Requests for additional Ecm=500 GeV Samples
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