Abstract
In this paper we propose a method to gain access to the top-quark width which exploits off-shell regions in the process \( {e}^{+}{e}^{-}\to {W}^{+}{W}^{-}b\overline{b} \). Working at next-to-leading order in QCD we show that carefully selected ratios of off-shell regions to on-shell regions in the reconstructed top and anti-top invariant mass spectra are, independently of the coupling g tbW , sensitive to the top-quark width. We explore this approach for different centre of mass energies and initial-state beam polarisations at e + e − colliders and briefly comment on the applicability of this method for a measurement of the top-quark width at the LHC.
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Liebler, S., Moortgat-Pick, G. & Papanastasiou, A.S. Probing the top-quark width through ratios of resonance contributions of \( {\mathrm{e}}^{+}{\mathrm{e}}^{-}\to {\mathrm{W}}^{+}{\mathrm{W}}^{-}\mathrm{b}\overline{\mathrm{b}} \) . J. High Energ. Phys. 2016, 99 (2016). https://doi.org/10.1007/JHEP03(2016)099
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DOI: https://doi.org/10.1007/JHEP03(2016)099