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Forward-backward asymmetries of lepton pairs in events with a large transverse momentum jet at hadron colliders

F. del Aguila·Ll. Ametller·P. Talavera
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Abstract

We discuss forward-backward charge asymmetries for lepton pair production in association with a large transverse momentum jet at hadron colliders. The measurement of the lepton charge asymmetry relative to the jet direction A_{FB}^j gives a new determination of the effective weak mixing angle sin^2{θ_{eff}^{lept}(M_Z^2)} with in principle a statistical precision after cuts of \sim 10^{-3} (8 x 10^{-3}) at LHC (Tevatron), due to the large cross section of the process with initial gluons. The identification of b jets also allows for the measurement of the bottom quark Z asymmetry A_{FB}^b at hadron colliders although with a lower precision than at LEP, the resulting statistical precision for sin^2{θ_{eff}^{lept}(M_Z^2)} being \sim 9 x 10^{-4} (2 x 10^{-2} at Tevatron).

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F. del Aguila, Ll. Ametller, P. Talavera. 2002-07-30. Forward-backward asymmetries of lepton pairs in events with a large transverse momentum jet at hadron colliders. https://doi.org/10.1103/physrevlett.89.161802

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