B^0-B^0 Mixing in Local Gauged Baryon and Lepton Numbers

Using the effective Hamiltonian method, we analyze the B0-B0 mixing in the extension of the standard model （SM） where baryon number and lepton number are local gauge symmetries. The numerical results indicate the correction from the extra particles to the mass difference ArnB is significant. There is a 60% enhancement compared to the SM prediction for AraB at most, which agrees with the current experimental result.