10–15 Dec 2023
Playa del Carmen
America/Cancun timezone

Measurement of dijet production in UPC with the ATLAS detector

14 Dec 2023, 11:30
30m
Playa del Carmen

Playa del Carmen

Iberostar TUCAN, Lote Hotelero Nº2, P.º Xaman - Ha, Playacar, 77710 Playa del Carmen, Q.R., Mexico
Session 4: Inclusive photonuclear interactions Inclusive photonuclear interactions

Speaker

Blair Daniel Seidlitz (Columbia University (US))

Description

In relativistic heavy ion collisions, the charged ions produce an intense flux of equivalent photons. Thus, photon-induced processes are the dominant interaction mechanism when the colliding nuclei have a transverse separation larger than the nuclear diameter. In these ultra-peripheral collisions (UPCs), the photon provides a clean, energetic probe of the partonic structure of the nucleus, analogous to deep inelastic scattering. This talk presents a measurement of jet production in UPCs performed with the ATLAS detector using high-statistics 2018 Pb+Pb data. Events are selected using requirements on jet production, rapidity gaps, and forward neutron emission to identify photo-nuclear hard-scattering processes. The precision of these measurements is augmented by studies of nuclear break-up effects, allowing for detailed comparisons with theoretical models in phase-space regions where significant nuclear PDF modifications are expected but not strongly constrained by existing data.

Presentation materials