Measurement of prompt and non-prompt J/ψ production in p–Pb collisions at √sNN= 8.16 TeV with ALICE at the LHC

Heavy quarks (charm and beauty) are essential probes of the quark-gluon plasma (QGP), a hot and dense medium created in heavy-ion collisions. Since the heavy-quark production in high-energy collisions occurs earlier than the formation time of the QGP, heavy quarks witness the whole evolution of the QGP. Measurements in proton-nucleus (pA) collisions provide the genuine testing ground to study possible modifications of heavy-quark production in the presence of a nucleus, which is necessary information to interpret the measurements in heavy-ion collisions. A valuable observable is the production of J/ψ mesons, a bound state of a cc pair. Their production can be prompt, meaning that they are either produced directly or from the decay of heavier charmonium states, or it can be non-prompt when originating from the decay of beauty hadrons. Therefore, a measurement of J/ψ which separates these contributions allows one to study charm and beauty quark production simultaneously. In this thesis work, the /ψ meson production was measured in p–Pb collisions at√sNN= 8.16 TeV using a high-pT electron enriched data sample collected using the Transition Radiation Detector (TRD). Based on the electron identification and tracking capabilities of the ALICE detector at the LHC, the J/ψ mesons are reconstructed in the dielectron decay channel at midrapidity. Relying on the long lifetime of beauty hadrons, prompt and non-promptJ/ψ contributions are separated on a statistical basis. The resulting pT dependent nuclear modification factors (RpA) of prompt and non-prompt J/ψ are consistent with unity within measured uncertainties at midrapidty in2<pT