22-30 July 2021
North-West University
Africa/Johannesburg timezone
More Information Coming Soon

Background decomposition in $Z\gamma$ events used in the search for high-mass resonances.

27 Jul 2021, 11:30
15m
Potchefstroom Campus (North-West University)

Potchefstroom Campus

North-West University

Oral Presentation Track B - Nuclear, Particle and Radiation Physics Nuclear, Particle and Radiation Physics

Speaker

Phuti Ntsoko Rapheeha (University of the Witwatersrand)

Description

The study present the measurement of the contribution, purity, of $Z + \gamma$ and $Z+$ jet background events in the search for high-mass $Z\gamma$ resonances. The study uses events were the $Z$ boson decays into a pairs of oppositely charged electrons or muons. The events used consist of 139 fb${}^{-1}$ of proton-proton, $pp$, collisions data at $\sqrt{s} = 13$ TeV, recorded by the ATLAS detector at the CERN Large Hadron Collider.
The measured purity of $Z+\gamma$ background events depends on the parameter $R$ that gives the correlation between the isolation and identification criteria for jets faking photons in $Z+$ jet events. A data-driven method that uses $\gamma\gamma$ events collected in the same detector conditions as the $Z\gamma$ events is used to determine $R$ in various bins of the photon transverse momentum or the invariant mass bins. The results are compared against results that are obtained using the $R$ computed using a $Z+$jet Monte Carlo sample and a data-driven method that uses $Z+\gamma$ events to estimate $R$.

Level for award;(Hons, MSc, PhD, N/A)?

PhD

Apply to be considered for a student ; award (Yes / No)?

Yes

Primary author

Phuti Ntsoko Rapheeha (University of the Witwatersrand)

Co-authors

Gaogalalwe Mokgatitswane (University of the Witwatersrand) Dr Salah-Eddine Dahbi (University of the Witwatersrand) XIFENG RUAN (University of the witwatersrand) Bruce Mellado (University of the Witwatersrand)

Presentation Materials

Peer reviewing

Paper