Model-independent search for the Abelian Z′ boson in the Bhabha process -: art. no. 115010

Model-independent observables to pick out the Abelian Z(') signal in the Bhabha process are introduced at energies rootsgreater than or equal to200 GeV. They measure separately the Z'-induced vector and axial-vector four-fermion contact couplings. The analysis of the LEP2 data constrains the value of the Z'-induced vector four-fermion coupling at the 2sigma confidence level that corresponds to the Abelian Z' boson with the mass of order 1 TeV.