Muon pair production in pion-nucleon interactions
Besides
having represented a powerful tool for the discovery of new particles (such as
J/Y,
Y, W, Z), the study of the production of muon pairs in hadronic interactions (Drell-Yan
process) conveys direct information about the interactions between the
fundamental constituents (quarks, gluons) and their distribution inside
hadrons. The approach is complementary to the Deep Inelastic Scattering of
leptons off hadrons, and can also be applied to unstable particles such as pions.
The
experiment Fermilab E615 (U. Chicago, Iowa
S., Princeton collaboration) studied the production of muon pairs in pion -
Nucleon
interactions, and collected data in 1982 and 1984. The measurement covered in
particular the kinematic region where most of the pion momentum is transferred
to the muon pairs, and effects related to the interactions between the two
valence quarks become visible, for example in the angular distribution of the
lepton pair.
