Z physics constraints on vector leptoquarks

We analyze the constraints on vector leptoquarks coming from radiative corrections to Z physics. We perform a global fitting to the LEP data including the oblique and non-universal contributions of the most general effective Lagrangian for vector leptoquarks, which exhibits the SU(2)L × U(1)Y gauge invariance. We show that the Z physics leads to stronger bounds on second and third generation vectors leptoquarks than the ones obtained from low energy and the current collider experiments.