J/Psi Photoproduction off the proton and neutron with CLAS12

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Understanding hadronic structure and interactions in terms of quark and gluon degrees of freedom,within the framework of Quantum Chromodynamics (QCD), is the main goal of modernnuclear/hadron physics. An important tool to further explore these fundamental properties is thestudy of heavy quarkonia with hadronic matter. The production of heavy quarkonia directly probesthe local colour (gluonic) fields in the nucleon and can reveal properties such as their spatialdistribution (building a picture of the internal components of the nucleon), the response tomomentum transfer within the system (how does the picture vary with energy) and the correlationwith valence quarks (the quarks that give the nucleon its properties such as charge).The first state of heavy quarkonia is the two quark system comprising of a bound charm-anti-charmpair, namely the J/Psi meson. With the available beam energy at Jefferson Lab now upgraded to 12GeV and a new detector system, CLAS12 in Hall-B on-line, the photo- and electroproductionofJ/Psi can now be studied. There is a considerable amount of J/Psi photoproduction data at highenergies but no data near threshold. Given the considerable change in dynamics between highenergy and the near-threshold regions, two recent experiments carried out on a proton and adeuterium target at CLAS12 will provide unique information on the gluonic fields within thenucleon at "real-world" hadronic energy scales.In addition to the studies of these fundamental QCD degrees of freedom, recent claims of thediscovery of pentaquark (5 quark) like structures from the LHCb have renewed interest in thischarmonium threshold region. These states, should they exist, are within the energy range availablein the above measurements and this data has the potential to provide compelling evidence for oragainst such states. Furthermore, CLAS12 is in the unique position to provide measurements fromproduction off a neutron (within deuterium) and thus check the necessity for isospin invariance tohold true regarding any "new" resonance claims. In simple terms, if a pentaquark resonance isproduced decaying to a J/Psi and proton, then one must also exist which decays to J/Psi and aneutron.The project aims and objectives are currently defined to:Study the particle identification efficiency of the CLAS12 detector system through the analysis ofelectron-positron pairs.Develop a standard cuts based analysis for the dataDevelop a machine learning algorithm to replicate and verify the above standard approach. Theexploitation of machine learning is still in its infancy within the hadronic physics community andany such development will provide valuable guidance for future analysis projects.Ultimately extract the cross-sections (the production probabilities) of J/Psi-proton and J/Psineutron.The project will be undertaken within the CLAS Collaboration at Jefferson Lab.