Search for D^0 - barD^0 Mixing in the Dalitz Plot Analysis of D^0 --> K_S^0 pi^+ pi^-

TL;DR

This paper investigates D0-D0bar mixing by analyzing the decay patterns of D0 --> K_S^0 pi+ pi- using Dalitz plot analysis, connecting decay time variations to mixing parameters, and finds results consistent with no mixing.

Contribution

It introduces a formalism linking decay time variation over the Dalitz plot to mixing parameters x and y, and applies it to experimental data to set limits on these parameters.

Findings

Parameters x and y are consistent with zero.

Limits on x: -4.7% to 8.6%.

Limits on y: -6.1% to 3.5%.

Abstract

The resonant substructure in D0 --> K0S pi+ pi- decays is described by a combination of ten quasi two-body intermediate states which include both CP-even and CP-odd eigenstates and one doubly-Cabibbo suppressed channel. We present a formalism that connects the variation in D0 decay time over the Dalitz plot with the mixing parameters, x and y, that describe off-shell and on-shell D0-D0B mixing. We analyze the CLEO II.V data sample and find the parameters x and y are consistent with zero. We limit (-4.7 < x < 8.6)% and (-6.1 < y < 3.5)% at the 95\% confidence level