NLO QCD predictions for off-shell t t ¯ $$ toverline{t} $$ and t t ¯ H $$ toverline{t}H $$ production and decay at a linear collider

We present predictions for $$ toverline{t} $$ and $$ toverline{t}h $$ production and decay at future lepton colliders including non-resonant and interference contributions up to next-to-leading order (nlo) in perturbative qcd. the obtained precision predictions are necessary for a future precise determination of the top-quark yukawa coupling, and allow for top-quark phenomenology in the continuum at an unprecedented level of accuracy. simulations are performed with the automated nlo monte-carlo framework whizard interfaced to the openloops matrix element generator.