ICHEP2018 SEOUL

Jul 4 – 11, 2018
COEX, SEOUL
Asia/Seoul timezone

Charmonium production in pp collisions with ALICE at the LHC

Jul 5, 2018, 9:18 AM
18m
205 (COEX, Seoul)

205

COEX, Seoul

Parallel Heavy Ions

Speaker

Lucas Altenkamper (University of Bergen (NO))

Description

In pp collisions at LHC energies, charmonium resonances are predominantly produced in hard scattering processes and a subsequent hadronization of the heavy quark pair into a bound state. The production process involves very different energy scales, with the initial quark pair being produced in a high-$Q^2$ process that allows for a perturbative treatment while the following formation of the bound state is a soft process. Moreover, recent observations have shown an enhancement of the $J/\psi$ production in high multiplicity pp collisions compared to minimum bias events at LHC energies. This suggests, that multi parton interactions (MPI) may also play a role in hard processes and not only, as initially thought, in soft particle production. The production of inclusive charmonia as a function of the event activity in pp collisions was studied by ALICE in different transverse momentum intervals at mid- and forward-rapidity. Measurements of the angular correlations between $J/\psi$ mesons and associated hadrons produced in the same event can shed light on the production of $J/\psi$ mesons as well as eventual global event correlations hypothesized to appear in high multiplicity events.

In this talk, we will present recent ALICE results on $J/\psi$ production as a function of event multiplicity in pp collisions at $\sqrt{s}=$13 TeV. These results will be discussed in comparison to measurements at different collision energies and model calculations. Additionally, we will present the current status on $J/\psi$ - hadron angular correlations in pp collisions at $\sqrt{s}=$13 TeV at mid-rapidity.

Primary author

Lucas Altenkamper (University of Bergen (NO))