Dalitz plot analysis of the D+ -> K- pi+ pi+ decay

TL;DR

This paper performs a detailed Dalitz plot analysis of the D+ -> K- pi+ pi+ decay, using a large dataset to explore different decay models and measure the contributing wave amplitudes and phases.

Contribution

It introduces a quasi model-independent partial wave analysis for the decay, improving understanding of the decay dynamics and including an isospin-two pi+pi+ S-wave contribution.

Findings

Better data agreement with inclusion of isospin-two pi+pi+ S-wave

Measured amplitude and phase of K pi and pi+pi+ S waves

Confirmed consistency with previous measurements, with improved precision

Abstract

We present a Dalitz plot analysis of the decay D+ -> K- pi+ pi+ based on 281 pb-1 of e+e- collision data produced at the psi(3770) by CESR and observed with the CLEO-c detector. We select 67086 candidate events with a small, ~1.1%, background for this analysis. When using a simple isobar model our results are consistent with the previous measurements done by E791. Since our sample is considerably larger we can explore alternative models. We find better agreement with data when we include an isospin-two pi+pi+ S-wave contribution. We apply a quasi model-independent partial wave analysis and measure the amplitude and phase of the K pi and pi+pi+ S waves in the range of invariant masses from the threshold to the maximum in this decay.