A non-perturbative calculation of the mass of the B-c

We present a calculation of the mass of the S-1(0) pseudoscalar (b) over bar c (B-c) state using a non-perturbative measurement from quenched lattice QCD, We find M-Bc = 6.386(9)(98)(15) GeV where the first error is statistical, the second systematic due to the quark mass ambiguities and quenching and the third the systematic error due to the estimation of mass of the eta(b). (C) 1999 Published by Elsevier Science B.V. All rights reserved