Strangeness in Quark Matter 2022 (SQM 2022)

Longitudinal decorrelation measurements from pp to A+A with the ATLAS detector

15 Jun 2022, 11:30

20m

GBR3

Talk Bulk matter phenomena, QCD phase diagram, and Critical point PA-Bulk matter phenomena, QCD phase diagram, and Critical point

Speaker

James Lawrence Nagle (University of Colorado Boulder)

Description

This talk presents new measurements of longitudinal flow decorrelations in 5.02 TeV and 13 TeV pp collisions and 5.44 TeV Xe+Xe collisions with the ATLAS detector. The measurements are performed using the two-particle correlation method with charged-particle tracks within |eta| < 2.5 and clusters within 4.0 < |eta| < 4.9. Due to the larger influence of non-flow effects in small collision systems, template-based subtraction procedures are developed and applied to the measurement. These effects are observed to play a role even in large systems such as 5.44 TeV Xe+Xe collisions. Flow decorrelations are characterized in terms of the ratio of the correlations with a large pseudorapidity gap to those with small pseudorapidity gap, r_n, where n is the flow harmonic moment. Results are reported for the slope of r_2 as a function of pseudorapidity gap as a function of charged-particle multiplicity for the pp and Xe+Xe collision systems. This gives some of the first detailed information on the correlation between longitudinal and transverse energy deposition in pp collisions.

Presentation materials

nagle_sqm_atlas_decorrelations_2022.pdf