TWOGEN—a simple Monte Carlo generator for two-photon reactions (original) (raw)

TWOGEN samples the transverse-transverse luminosity function for real and virtual photons, then weights events with any user-supplied cross section TT (!X) i n a \hit or miss" sampling, using a simple method to avoid the singularity at the minimum electron angle # min = 0 . E v ents within dened kinematic limits are accepted and the corresponding cross section is estimated, together with the eective luminosity of the run. Functions implemented for TT include the production cross sections for lepton pairs, for the formation of narrow resonances and for hadron production in tagged, deep inelastic scattering. A comparison is made with an existing Monte Carlo Generator and a simple analytic approximation.