L. M. Zhang, Z. P. Zhang, J. Li, for the Belle Collaboration
Published 2006-01-17, updated 2006-04-19Version 2
We report the results of a search for D0-D0bar mixing in D0 -> K+ pi- decays based on 400 fb^{-1} of data accumulated by the Belle detector at KEKB. Both assuming CP conservation and allowing for CP violation, we fit the decay-time distribution for the mixing parameters x' and y', as well as for the parameter R_D, the ratio of doubly-Cabibbo-suppressed decays to Cabibbo-favored decays. The 95% confidence level region in the (x'^2,y') plane is obtained using a frequentist method. Assuming CP conservation, we find x'^2<0.72 x 10^{-3} and -9.9 x 10^{-3}<y'<6.8 x 10^{-3} at the 95% confidence level; these are the most stringent constraints on the mixing parameters to date. The no-mixing point (0,0) has a confidence level of 3.9%. Assuming no mixing, we measure R_D=(0.377+-0.008+-0.005)%.
Comments: 6 pages, 3 figures, 1 table; replaced with the version of Phys. Rev. Lett
Journal: Phys.Rev.Lett.96:151801,2006
Search for D^0-D^0bar mixing in D^0 -> K+pi- decays and measurement of the doubly-Cabibbo-suppressed decay rate
Evidence for $D^0 - \bar{D}^0$ Mixing
Observation of the decay $B_s^0\to J/ψη$ and Evidence for $B_s^0\to J/ψη'$
