3–7 Apr 2017
University of Birmingham
Europe/London timezone

Studies of the underlying-event properties and of hard double parton scattering with the ATLAS detector

5 Apr 2017, 11:00
20m
Small Lecture Theatre, Poynting Building

Small Lecture Theatre, Poynting Building

WG2) Low x and Diffraction WG2 Low x and Diffraction

Speaker

Oleg Kuprash (Tel Aviv University (IL))

Description

A correct modelling of the underlying event in proton-proton collisions is important for the proper simulation of kinematic distributions of high-energy collisions. The ATLAS collaboration extended previous studies at 7 TeV with a leading track or jet or Z boson by a new study at 13 TeV, measuring the number and transverse-momentum sum of charged particles as a function of pseudorapidity and azimuthal angle in dependence of the reconstructed leading track. These measurements are sensitive to the underlying-event as well as the onset of hard emissions. The results are compared to predictions of several MC generators.

Inclusive four-jet events produced in proton--proton collisions at a center-of-mass energy of 7 TeV have been analyzed for the presence of hard double parton scattering collected with the ATLAS detector. The contribution of hard double parton scattering to the production of four-jet events has been extracted using an artificial neural network. The assumption was made that hard double parton scattering can be represented by a random combination of dijet events. In addition, a sample enriched with double parton scattering events was extracted and several characteristics of these events were studied. The measurements have been compared to different MC generator predictions.

Authors

Marc Escalier (LAL-Orsay (FR)) Oleg Kuprash (Tel Aviv University (IL))

Presentation materials