Probing the top-quark width through ratios of resonance contributions of $e^+e^-\rightarrow W^+W^-b\bar{b}$

Liebler, Stefan; Papanastasiou, Andrew S.; Moortgat-Pick, Gudrid

Preprint/Internal Report

PUBDB-2015-05200

Probing the top-quark width through ratios of resonance contributions of $e^+e^-\rightarrow W^+W^-b\bar{b}$

Liebler, S.DESY* ; Moortgat-Pick, G.DESY* ; Papanastasiou, A. S.

2015

This record in other databases:

Report No.: DESY-15-169; arXiv:1511.02350

Abstract: We exploit offshell regions in the process $e^+e^-\rightarrow W^+W^-b\bar{b}$ to gain access to the top-quark width. Working at next-to-leading order in QCD we show that carefully selected ratios of offshell regions to onshell regions in the reconstructed top and antitop invariant mass spectra are, \emph{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.

Keyword(s): top: width ; beam: polarization ; off-shell ; quantum chromodynamics ; initial state ; mass spectrum ; CERN LHC Coll ; anti-top