Given the gluonic observable W(t)=t∂t∂(t2⟨E⟩)=t2(2⟨E⟩+t∂t∂⟨E⟩)
For the δμ correction to a gluonic observable W, where the counterterm lagrangian Lc=δμuˉu+δμdˉd with ru=+1 and rd=−1. Expanding the interaction e−Lc we have ⟨W⟩=⟨W⟩0−⟨W∫dx′(δμuˉu+δμdˉd)(x′)⟩0=⟨W⟩0−⟨W∫dx(δμχˉuiγ5χu−δμχˉdiγ5χd)(x)⟩0=⟨W⟩0+iδμ⟨W(Tr[∫dxSu(x,x)γ5]−Tr[∫dxSd(x,x)γ5])⟩ Where we got an extra minus sign from the fermion loop