Probing the Heavy Flavor Content in t tbar Events and Using t tbar Events as a Calibration Tool at CMS

TL;DR

This paper measures the top quark's branching ratio to Wb in ttbar events at CMS and explores using these events to calibrate b-tagging efficiency, employing data-driven background control methods.

Contribution

It introduces two analyses for measuring the top quark's branching ratio and assesses the feasibility of using ttbar events for b-tagging calibration at CMS.

Findings

Estimated the ratio R of top quark decay modes.

Demonstrated the potential of ttbar events for b-tagging calibration.

Presented data-driven background control techniques.

Abstract

We present two analyses dedicated to measure the ratio of branching ratios of the top quark, R=B(t->Wb)/(t->Wq) (where q=d,s,b), using ttbar events with either one or two prompt isolated leptons (e or mu) in the final state. Furthermore the framework of the dileptonic analysis was used also for a feasibility study of the measurement of b-tagging efficiency, by assuming the R value to be the Standard Model one. Data-driven techniques to control the background in the selected events are discussed and the expected simulation results are presented.