Charmed mesons as a probe for Triple Parton Scattering

The recent observation of three $J$/$\psi$ production by the Compact Muon Solenoid (CMS) Collaboration raised large interest in Multiple Parton Scattering. While the study of multiple $hard$ parton scattering at large $x$ is limited by cross section, extending the investigation to lower mass final states is experimentally challenging because of the huge background expected at LHC. Only recently, for the first time the simultaneous production of three $J$/$\psi$ mesons have been interpreted as originating from Triple Parton Scattering (TPS) processes, even with a precision on the measured cross section limited by statistics. In this thesis, I investigated a novel mesonic final state which can increase the sensitivity to TPS. On the one hand, the CMS experiment excels in muons reconstruction, $J$/$\psi$ in their muonic decay can be clearly reconstructed and are then optimal trigger for the process, on the other hand the cross section for an open charm meson is larger than the one for a $c\bar{c}$ state. A final state with two $J$/$\psi$ and a $D$$^{∗}$ is expected to provide a more suitable way to directly access TPS production at LHC, with a strong control of experimental systematics. In this work, the $J$/$\psi$ are reconstructed by their decay into muons pair, meanwhile, the $D$$^{∗}$ mesons are reconstructed by its most probable decay chain: $D$$^{∗+}$ → $D$$^{0}$$\pi$$_{slow}^{+}$ → $K$ $^{−}$$\pi$$^{+}$$\pi$$_{slow}^{+}$. After setup the Monte Carlo generation of signal and background samples, a study has been done deeply analyzing event kinematic and topology providing an indication on possible discriminating observables.