ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2008, vol. 77, p. -
Improved search for D0-D̄0 mixing using semileptonic decays at Belle
A search for mixing in the neutral D meson system has been performed using semileptonic D0→K(*)-e+ν and D0→K(*)-μ+ν decays. Neutral D mesons from D*+→D0πs+ decays are used and the flavor at production is tagged by the charge of the slow pion. The measurement is performed using 492fb-1 of data recorded by the Belle detector. From the yield of right-sign and wrong-sign decays arising from nonmixed and mixed events, respectively, we measure the ratio of the time-integrated mixing rate to the unmixed rate to be RM=(1.3±2.2±2.0)×10-4. This corresponds to an upper limit of RM<6.1×10-4 at the 90% C.L. © 2008 The American Physical Society.