Dortmund 2021 – wissenschaftliches Programm
T 28.1: Vortrag
Dienstag, 16. März 2021, 16:00–16:15, Tc
Measurements of differential cross sections for tt production at √s=13 TeV with the CMS experiment — Maria Aldaya, Olaf Behnke, •Henriette Petersen, Mykola Savitskyi, Rafael Sosa, and Sebastian Wuchterl — Deutsches Elektronen Synchrotron (DESY)
Precision tests of the Standard Model are of utmost importance in particle physics, not only in order to test existing theories but also to probe the realm of new physics. The top quark is of particular interest in this context, as its heavy mass can link it to production- and decay-modes of new processes at higher energy scales. In this talk measurements of differential cross sections for tt production at √s=13 TeV will be presented. The analysis is based on data obtained with the CMS experiment during 2016, 2017 and 2018 in Run 2 of the LHC, corresponding to an integrated luminosity of 137 fb−1. In this period of time more than 100 million pp collisions with a tt pair in the final state have occurred, and therefore, Run 2 facilitates unprecedented precision in measurements of kinematic spectra and topologies in these events. The analysis is performed using the dileptonic decay channel. We perform differential measurements of the tt production cross section in bins of kinematic properties of the visible decay products, tt system and top quark. In this talk the general analysis strategy will be presented. This includes an overview of the event selection, kinematic reconstruction of the tt system, cross section unfolding procedure and results for full Run 2 differential cross sections compared to MC predictions based on NLO QCD models matched to parton showers.