# EPS-HEP2021 conference

26-30 July 2021
Zoom
Europe/Berlin timezone

## Measurement of light-by-light scattering in ultra-peripheral Pb+Pb collisions with the ATLAS detector

29 Jul 2021, 16:30
15m
Zoom

#### Zoom

Parallel session talk Heavy Ion Physics

### Speaker

Mateusz Dyndal (AGH UST Krakow)

### Description

In ultra-relativistic heavy-ion collisions, one expects copious rates of $\gamma+\gamma$ processes through the interaction of the large electromagnetic fields of the nuclei which can lead to light-by-light scattering via loop diagrams. This process was directly observed for the first time in UPCs at the LHC by ATLAS. Final measurements of light-by-light scattering with full run 2 dataset with substantially reduced uncertainties will be presented. This process provides a precise and unique opportunity to investigate extensions of the Standard Model such as axion-like particles.

Collaboration / Activity ATLAS Lidija Zivkovic Lidija.Zivkovic@cern.ch