Speaker
Description
Charm and beauty are heavy quarks with observed masses of
1.28 GeV/c 2 and 4.18 GeV/c 2 respectively. They are produced
in initial hard scattering processes. Due to their small
formation time (∆t~0.1 fm/c) as compared to the formation
time of QGP ( ∆t~0.3 fm/c) at the LHC, they experience all the
stages occuring during the time evolution of the hot and dense
medium produced in heavy-ion collisions. Therefore, the
measurement of open charm and beauty production allows
probing QGP properties and investigating the color charge and
mass dependence of the parton in-medium energy loss.
Moreover, due to their large masses (m c , m b >> Λ QCD ) their pp
production cross-sections are calculable within the domain of
perturbative QCD constituting an excellent test of pQCD
calculations.
The study of D-meson yield in pp collisions as a function of
charged-particle multiplicity helps to understand the processes
involved in the production of charm quarks. Moreover,
analyzing the charm production processes could help in
learning the basic differences between hard and soft processes
of particle production. Along with that, they also serve as a
reference for the similar measurements in p-Pb and Pb-Pb
collisions.
In this contribution, D + meson yield as a function of charged-
particle multiplicity will be presented. Furthermore, the
comparison with J/ψ yield at 7 TeV, 13 TeV and to D + -meson
yield at 7 TeV in pp collisions will be shown.
