# 10th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions

May 31, 2020 to June 5, 2020
Online
US/Central timezone

## DCA studies for separating prompt and non-prompt dielectrons in p–Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV with ALICE

Jun 2, 2020, 7:30 AM
1h 20m
Online

#### Online

Poster Electroweak Probes

### Speaker

Horst Sebastian Scheid (Johann-Wolfgang-Goethe Univ. (DE))

### Description

Dileptons are a prime probe of the deconfined state of strongly interacting matter, the Quark–Gluon Plasma (QGP), produced in high energy heavy ion collisions, as they are not affected by secondary strong interactions. A measurement of the thermal radiation from the QGP in the dielectron intermediate mass region allows to estimate the medium temperature. In this region the main component of the dielectron continuum is due to correlated semileptonic decays of B and D mesons. The proper decay length for B-mesons is $c\tau \approx$ 500 $\mu$m and for D mesons it is 100-300 $\mu$m, hence the reconstructed decay electrons do not point to the primary vertex of the collision.
Combining the measured distance of closest approach (DCA) of each single electron into a pair variable DCA$\rm _{ee}$ gives the possibility to separate prompt from non-prompt dielectron pairs or the charm and beauty contributions from each other. In small collisions systems this approach can be used to measure a possible modification of the heavy-flavour sources by cold nuclear matter effects, or to identify thermal radiation on top of the heavy-flavour contributions and with this serve as a reference for measurements in Pb–Pb collisions.
We will present most recent studies in p–Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV.

Collaboration (if applicable) ALICE Electroweak Probes Poster

### Primary author

Horst Sebastian Scheid (Johann-Wolfgang-Goethe Univ. (DE))

### Presentation materials

 Poster_Scheid_HP2020.pdf Video_Scheid_HP2020.mp4 Zoom meeting