Measurement of the c-jet mistagging efficiency in tt¯ events using pp collision data at √s=13 TeV collected with the ATLAS detector

• Autor(a) principal: Castro, N. F.
• Data de Publicação: 2022
• Outros Autores: Fiolhais, M. C. N., Gonçalo, J. R., Onofre, A., Veloso, F., Wolters, H., Atlas Collaboration
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/103242

A technique is presented to measure the efficiency with which c-jets are mistagged as b-jets (mistagging efficiency) using t ¯t events, where one of theW bosons decays into an electron or muon and a neutrino and the other decays into a quark–antiquark pair. The measurement utilises the relatively large and known W → cs branching ratio, which allows ameasurement to be made in an inclusive c-jet sample. The data sample used was collected by the ATLAS detector at √ s = 13 TeV and corresponds to an integrated luminosity of 139 fb−1. Events are reconstructed using a kinematic likelihood technique which selects the mapping between jets and t ¯t decay products that yields the highest likelihood value. The distribution of the b-tagging discriminant for jets from the hadronic W decays in data is compared with that in simulation to extract the mistagging efficiency as a function of jet transverse momentum. The total uncertainties are in the range 3–17%. The measurements generally agree with those in simulation but there are some differences in the region corresponding to the most stringent b-jet tagging requirement.