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`Determining the strong coupling constant at NNLO from jet observables'

Abstract: Event-shape observables played historically a very important 
role in QCD phenomenology at electron-positron colliders, allowing also 
a precise extraction of the strong coupling constant. In recent years, 
the computation of the NNLO corrections to electron-positron 
annihilation into three jets led to several improvements in the 
determination of strong coupling constant from event-shape observables. 
The matching of fixed order NNLO result with resummed calculation and 
the study of moment of event shapes gives also some interesting 
insights about hadronisation corrections. The talk will review the most 
recent developments in this field.
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