Complete Corrections of O ( αα s ) to the Decay of the Z Boson into Bottom Quarks

For the vertex corrections to the partial decay rate Γ(Z → bb̄) involving the top quark only the leading terms of order ααs in the 1/Mt expansion are known. In this work we compute the missing next-to-leading corrections. Thus at O(ααs) the complete corrections to the decay of the Z boson into bottom quarks are at hand. PACS numbers: 12.38.Bx, 13.30.Eg, 13.38.Dg, 14.65.Fy