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Search for pair and single production of vectorlike quarks in final states with at least one Z boson decaying into a pair of electrons or muons in pp collision data collected with the ATLAS detector at vs=13??TeV
journal contribution
posted on 2023-06-09, 18:54 authored by N L Abraham, Benedict AllbrookeBenedict Allbrooke, Lily AsquithLily Asquith, Alessandro CerriAlessandro Cerri, Samuel Jones, Antonella De SantoAntonella De Santo, Fabrizio SalvatoreFabrizio Salvatore, Kate ShawKate Shaw, Thomas StevensonThomas Stevenson, K Suruliz, Mark SuttonMark Sutton, Fabio Tresoldi, Fabrizio Trovato, Iacopo Vivarelli, E Winkels, The ATLAS Collaboration, othersA search for vectorlike quarks is presented, which targets their decay into a Z boson and a third-generation Standard Model quark. In the case of a vectorlike quark T (B) with charge +2/3e (-1/3e), the decay searched for is T?Zt (B?Zb). Data for this analysis were taken during 2015 and 2016 with the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 36.1??fb-1 of pp collisions at vs=13??TeV. The final state used is characterized by the presence of b-tagged jets, as well as a Z boson with high transverse momentum, which is reconstructed from a pair of opposite-sign same-flavor leptons. Pair and single production of vectorlike quarks are both taken into account and are each searched for using optimized dileptonic exclusive and trileptonic inclusive event selections. In these selections, the high scalar sum of jet transverse momenta, the presence of high-transverse-momentum large-radius jets, as well as—in the case of the single-production selections—the presence of forward jets are used. No significant excess over the background-only hypothesis is found and exclusion limits at 95% confidence level allow masses of vectorlike quarks of mT>1030??GeV (mT>1210??GeV) and mB>1010??GeV (mB>1140??GeV) in the singlet (doublet) model. In the case of 100% branching ratio for T?Zt (B?Zb), the limits are mT>1340??GeV (mB>1220??GeV). Limits at 95% confidence level are also set on the coupling to Standard Model quarks for given vectorlike quark masses.
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Publication status
- Published
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- Published version
Journal
Physical Review DISSN
2470-0010Publisher
American Physical SocietyExternal DOI
Issue
112010Volume
98Page range
1-53Department affiliated with
- Physics and Astronomy Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2019-09-23First Open Access (FOA) Date
2019-09-23First Compliant Deposit (FCD) Date
2019-09-03Usage metrics
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