ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2008, vol. 78, p. -
Measurement of the mass difference m(B0)-m(B+)
Using 230×106 BB̄ events recorded with the BABAR detector at the e+e- storage rings PEP-II, we reconstruct approximately 4100 B0→J/ψK+π- and 9930 B+→J/ψK+ decays with J/ψ→μ+μ- and e+e-. From the measured B-momentum distributions in the e+e- rest frame, we determine the mass difference m(B0)-m(B+)=(+0. 33±0.05±0.03)MeV/c2. © 2008 The American Physical Society.