Measurement ofD0−D¯0mixing and search for indirectCPviolation usingD0→KS0π+π−decays

We report a measurement of D-0-(D) over bar(0) mixing parameters and a search for indirect CP violation through a time-dependent amplitude analysis of D-0 -> K-S(0)pi(+)pi(-) decays. The results are based on 921 fb(-1) of data accumulated with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. Assuming CP conservation, we measure the mixing parameters x = (0.56 +/- 0.19(-0.09-0.09)(+0.03+0.06))% and y = (0.30 +/- 0.15(-0.05-0.06)(+0.04+0.03))%, where the errors are statistical, experimental systematic, and systematic due to the amplitude model, respectively. With CP violation allowed, the parameters vertical bar q/p vertical bar = 0.90(-0.15-0.04-0.05)(+0.16+0.05+0.06) and arg(q/p) = (- 6 +/- 11 +/- 3(-4)(+3))degrees are found to be consistent with conservation of CP symmetry in mixing and in the interference between mixing and decay, respectively.