Jun 24 – 25, 2019
Prague, Czech Republic
Europe/Prague timezone

Differential cross-section measurement of the associated production of a top-quark pair and a Z boson

Jun 24, 2019, 4:40 PM
20m
Lecture room 103 (Prague, Czech Republic)

Lecture room 103

Prague, Czech Republic

Czech Technical University in Prague Břehová 7, 115 19 Prague, Czech Republic

Speaker

Dominik Babal (Comenius University (SK))

Description

Increasing center-of-mass energy of 𝑝𝑝 collisions and higher luminosity at the LHC enables us to study rare processes of the Standard Model. This analysis uses full Run 2 data with total integrated luminosity of 139 fb$^{-1}$ for the first differential measurement of $𝑡\bar{t}𝑍$ production cross-section at the ATLAS experiment. The methodology of the measurement is based on the Iterative Bayesian Unfolding (IBU). This method, which is based on Bayes' theorem, does not require matrix inversion and is theoretically well grounded. Together with iterative approach, the IBU ensures relatively fast and stable convergence to final unfolded distribution. The preliminary results for tetralepton signature, where 4 leptons are identified in the final state (dileptonic decay of top-quark pair and leptonic decay of Z boson to two charged leptons), will be presented.

Primary authors

Dominik Babal (Comenius University (SK)) Michal Dubovsky (Comenius University (SK)) Michal Racko (Comenius University (SK)) Pavol Bartos (Comenius University (SK))

Presentation materials