Quark Matter 2018

Measurement of low-mass dielectrons in minimum-bias and high-multiplicity pp collisions at 13 TeV with ALICE

15 May 2018, 17:00

2h 40m

First floor and third floor (Palazzo del Casinò)

Poster Electromagnetic and weak probes Poster Session

Speaker

Ivan Vorobyev (Technische Universitaet Muenchen (DE))

Description

Electron-positron pairs are a unique experimental tool to investigate the hot and dense medium created in ultra-relativistic heavy-ion collisions. Such pairs are produced during all stages of the collision and do not interact strongly. Therefore, they carry information about the medium properties and the whole space-time evolution of the system.

Measurements of dielectron production in minimum-bias proton-proton collisions provide an important vacuum reference for any modifications observed in heavy-ion collisions. Moreover, the measurement of e${}^{+}$e${}^{-}$ pairs from semi-leptonic decays of correlated heavy-flavour hadrons in the intermediate-mass region (1.2 < mee < 2.9 GeV/$c^2$) allow further studies and understandings of the primordial heavy-flavour production. Finally, recent studies of proton-proton collisions with high charged-particle multiplicities showed interesting results similar to the observations previously done in heavy-ion collisions. Measurements of low-mass dielectrons could provide further insight into the underlying physics processes.

In this poster we present the latest results of the dielectron analysis with ALICE in pp collisions at $\sqrt{s}=13$ TeV. A particular focus of the discussion is put on the modification of dielectron spectrum in pp collisions collected with a trigger on high charged-particle multiplicities compared to the minimum-bias events.

Presentation materials

QM18_poster_IV_lmee13TeV.pdf