D~0-~0 mixing sensitivity estimation at Belle II in wrong-sign decays D~0→K~+π~-π~0 via time-dependent amplitude analysis

【摘要】 The sensitivity of the D⁰-⁰ mixing parameters x and y is estimated in the wrong-sign decay D⁰→K⁺π^-π⁰ by time-dependent amplitude analysis. The resolution of the D⁰ lifetime is essential in time-dependent Dalitz analyses. The Belle II detector, which aims to collect a total integrated luminosity of 50 ab^-1 of data, has σ = 140 fs in Monte Carlo studies, a factor of two improvement over that of Belle and Ba Bar, so the produced Dalitz signal Monte Carlo samples are smeared with this resolution. Then a time-dependent Dalitz plot fitting is performed on these smeared samples, and the sensitivity of D⁰-⁰mixing parameters are σ_x = 0.057% and σ_y = 0.049%. These are about an order of magnitude improvement on current experimental results, without considering background effects.更多还原

【Abstract】 The sensitivity of the D⁰-⁰ mixing parameters x and y is estimated in the wrong-sign decay D⁰→K⁺π^-π⁰ by time-dependent amplitude analysis. The resolution of the D⁰ lifetime is essential in time-dependent Dalitz analyses. The Belle II detector, which aims to collect a total integrated luminosity of 50 ab^-1 of data, has σ = 140 fs in Monte Carlo studies, a factor of two improvement over that of Belle and Ba Bar, so the produced Dalitz signal Monte Carlo samples are smeared with this resolution. Then a time-dependent Dalitz plot fitting is performed on these smeared samples, and the sensitivity of D⁰-⁰mixing parameters are σ_x = 0.057% and σ_y = 0.049%. These are about an order of magnitude improvement on current experimental results, without considering background effects.更多还原