D0--anti-D0 mixing results from BaBar by analysis of D0 --> K+ pi- pi0 Dalitz-plot regions

TL;DR

This paper reports a search for D0--anti-D0 mixing using D0 --> K+ pi- pi0 decays, employing a novel tagging technique and analyzing a large dataset from BaBar, finding no significant evidence of mixing.

Contribution

It introduces a new tagging method for Dalitz-plot analysis and applies it to D0 mixing search with a comprehensive dataset from BaBar.

Findings

Upper limit on mixing parameter R_M < 0.054% at 95% confidence

Data are consistent with no mixing at 4.5% confidence level

Branching ratio for D0 --> K+ pi- pi0 measured

Abstract

We present a preliminary search for D0--anti-D0 mixing using the decays D0 --> K+ pi- pi0, additionally presenting Dalitz-plot distributions and a measurement of the branching ratio for this mode. A new tagging technique is used to produce the doubly Cabibbo-suppressed Dalitz plot, which in turn is used to motivate the method used for the D-mixing search. We analyze 230.4fb-1 of data collected from the BaBar detector at the PEP-II collider. Assuming CP conservation, we find R_M < 0.054% with 95% confidence, and we estimate that the data are consistent with no mixing at a 4.5% confidence level. We present D-mixing results both with and without the assumption of CP conservation.