Speaker
Jun Su
(University of Pittsburgh (US))
Description
The t-channel production and decay of single top quarks is a unique probe of the Wtb vertex, providing simultaneous sensitivity to all of the "anomalous couplings", V_L, V_R, g_L and g_R. These four effective anomalous couplings have a direct connection with dimension-six operators coefficients in the effective field theory framework. To obtain constraints in the space of these parameters the triple differential decay rate of semileptonic top-quark decays collected in 20.3 fb^{-1} of proton--proton collisions at \sqrt{s} = 8 TeV using the ATLAS detector. Detector effects (resolution and efficiency) are deconvolved from the observed signal using novel Fourier techniques in particular a higher dimensional variant of the ordinary convolution theorem. Constraints on the top-quark polarization and the imaginary part of the coupling constant g_R are the world's most precise.
Author
ATLAS Collaboration
(CERN)
