# Quark Matter 2018

13-19 May 2018
Venice, Italy
Europe/Zurich timezone
The organisers warmly thank all participants for such a lively QM2018! See you in China in 2019!

## Measurement of Ds+/D+ as a function of transverse momentum and charged-particle multiplicity in pp, p-Pb and Pb-Pb collisions with ALICE

15 May 2018, 17:00
2h 40m
First floor and third floor (Palazzo del Casinò)

### First floor and third floor

#### Palazzo del Casinò

Poster Open heavy flavour

### Speaker

Fabrizio Grosa (Politecnico di Torino (IT))

### Description

Heavy quarks (charm or beauty) are powerful probes to study and characterise the properties of the deconfined medium created in high-energy heavy-ion collisions, the Quark-Gluon Plasma (QGP). Because of their large masses, heavy quarks are produced in initial hard-scattering processes, and they subsequently experience the whole system evolution, interacting with the medium constituents. The observation of a large suppression of the heavy-flavour hadron yields at intermediate/high transverse momentum ($p_{\rm T}$) in central Pb-Pb collisions with respect to those in pp collisions provides a strong evidence of the in-medium parton energy loss. Moreover, the measurement of heavy-flavour hadrons with strange-quark content (i.e. ${\rm D^+_{s}}$ mesons) can give insight into the heavy-quark hadronisation mechanism. If a fraction of charm quarks hadronises via coalescence, the relative abundance of ${\rm D^+_{s}}$ with respect to non-strange D mesons is expected to be larger in heavy-ion collisions compared to pp collisions, due to the enhanced production of strange quarks in the QGP. Furthermore, an enhanced production of strange and multi-strange hadrons was recently observed in high-multiplicity pp and p-Pb collisions. For these reasons, the measurement of the production of ${\rm D^+_{s}}$ mesons compared to that of non-strange D mesons as a function of the charged-particle multiplicity (${\rm d}N_{\rm ch}/{\rm d}\eta$) is interesting to study a possible enhancement of particles with strange-quark content in pp and p-Pb collisions in the heavy-quark sector, similar to the one observed for light hadrons.

In this poster, the measurement of ${\rm D^+_{s}}/{\rm D^+}$ yield ratios as a function of $p_{\rm T}$ in pp collisions at $\sqrt{s}=7~{\rm TeV}$ and Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02~{\rm TeV}$, and as a function of ${\rm d}N_{\rm ch}/{\rm d}\eta$ in p-Pb and Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02~{\rm TeV}$, will be presented.

Collaboration ALICE Experiment Presenter name already specified

### Primary author

Fabrizio Grosa (Politecnico di Torino (IT))