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Common Aspects in Searches for New Physics in \(t\bar{t}\) Final States with Additional Heavy-Flavor Jets

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Search for New Physics in tt ̅ Final States with Additional Heavy-Flavor Jets with the ATLAS Detector

Part of the book series: Springer Theses ((Springer Theses))

Abstract

This chapter describes the commonalities in event preselection, background modeling and treatment of systematic uncertainties for the different analyses in the \(t\bar{t}+\mathrm {HF}\) final state. A very precise modeling of the \(t\bar{t}\)+jets and \(t\bar{t}+b\bar{b}\) backgrounds is crucial for the analyses and will be discussed in detail. Finally, the quality of the modeling that is achieved is illustrated with a comparison to ATLAS data.

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Notes

  1. 1.

    In the following the word “lepton” is used to refer to either an electron or a muon, assumed to originate from the decay of a W boson or a \(\tau \) lepton.

  2. 2.

    The top-quark kinematics are measured at the partonic level, after final-state radiation. This is equivalent to the status code 3 in Pythia.

  3. 3.

    The MC jet flavor is defined by looking at partons with \(p_{\mathrm {T}}>5\,{{\mathrm {\ Ge\!V}}}\) within a \(\Delta R<0.3\) cone around the jet direction. If a b-quark is found, the jet is labeled with b origin. If no b-quarks are found, c-quarks are considered. If no c-quarks are found either, a jet is labeled as a light jet.

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  1. Instituto de Física de Altas Energías, Universitat Autónoma de Barcelona, Bellaterra, Barcelona, Spain

    Javier Montejo Berlingen

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Montejo Berlingen, J. (2016). Common Aspects in Searches for New Physics in \(t\bar{t}\) Final States with Additional Heavy-Flavor Jets. In: Search for New Physics in tt ̅ Final States with Additional Heavy-Flavor Jets with the ATLAS Detector. Springer Theses. Springer, Cham. https://doi.org/10.1007/978-3-319-41051-7_5

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