Measurement of the mass differencem(B0)−m(B+)

Abstract

Using 230×106 BB¯ 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.Received 6 May 2008DOI:https://doi.org/10.1103/PhysRevD.78.011103©2008 American Physical Society