Charm and prompt photon production with EPOS

The implementation of heavy quarks and prompt photons in EPOS is presented. One of the interests of event generators is their capability to reproduce exclusive observables. Our results for charms and prompt photons, in p-p collisions at $\sqrt s = 7{\rm{ TeV}}$, are compared with experiments and FONLL calculations [1]

EPOS

International audienceWe summarize the main features of the hadronic interaction model EPOS, which is used for cosmic ray air shower simulations but also for p-p, p-A, and A-A collisions to be compared with experimental data from LHC and RHIC

Saturation scale, MPI and underlying events

International audienceThe consistent description of hadronic interactions at all scales is a longstanding problem. The best description of minimum bias events and underlyingevents are usually obtain using either different parameter tuning for a givenevent generator or even using different models. In the hadronic interactionmodel EPOS, it is now possible to take into account the number of elementaryscattering in a unified way between proton-proton and nuclear collisions tocompute the saturation scale with the only assumption to recover factorizationat the highest scale. The hard scatterings are then dependent on the number ofparton scatterings event by event. Thanks to this new treatment and to thecollective hadronization of the high density core, both non-perturbative andperturbative QCD scales can be described consistently for any mass or center-of-mass collision energy

Charm and prompt photon production with EPOS

International audienceThe implementation of heavy quarks and prompt photons in EPOS is presented. One of the interests of event generators is their capability to reproduce exclusive observables. Our results for charms and prompt photons, in p-p collisions at $\sqrt s = 7{\rm{ TeV}}$, are compared with experiments and FONLL calculations [1]

Charm production in high multiplicity pp events

International audienceStudying proton-proton scattering at 7 TeV, the ALICE collaboration found the unexpected result that the D meson multiplicity increases more than linear as a function of the charged particle multiplicity. We try to understand this behavior using the EPOS3 approach. Two issues play an important role in this context: multiple scattering, in particular its impact on multiplicity fluctuations, and the collective hydrodynamic expansion. These data contain therefore valuable information about very basic features of the reaction mechanism in proton- proton collisions

EPOS

We summarize the main features of the hadronic interaction model EPOS, which is used for cosmic ray air shower simulations but also for p-p, p-A, and A-A collisions to be compared with experimental data from LHC and RHIC

System size dependence of particle production in EPOS

International audienceThe aim of this paper is to understand particle production for different collision systems, namely proton-proton (pp), proton-nucleus (pA), and nucleus-nucleus (AA) scattering at the LHC. We will investigate in particular particle yields and ratios versus multiplicity, using the same multiplicity definition for the three different systems, in order to analyse in a compact way the evolution of particle production with the system size and the origin of a very different system size dependence of the different particles

Resonance production in high energy collisions from small to big systems

The aim of this paper is to understand resonance production (and more generally particle production) for different collision systems, namely proton-proton (pp), proton-nucleus (pA), and nucleus-nucleus (AA) scattering at the LHC. We will investigate in particular particle yields and ratios versus multiplicity, using the same multiplicity definition for the three different systems, in order to analyse in a compact way the evolution of particle production with the system size and the origin of a very different system size dependence of the different particles

Resonance production in high energy collisions from small to big systems

International audienceThe aim of this paper is to understand resonance production (and more generally particle production) for different collision systems, namely proton-proton (pp), proton-nucleus (pA), and nucleus-nucleus (AA) scattering at the LHC. We will investigate in particular particle yields and ratios versus multiplicity, using the same multiplicity definition for the three different systems, in order to analyse in a compact way the evolution of particle production with the system size and the origin of a very different system size dependence of the different particles