Model Independent Measurement of Form Factors in the Decay D^+ --> K^- pi^+ e^+ nu_e

TL;DR

This paper reports model-independent measurements of form factors in the decay D+ -> K- pi+ e+ nu_e, confirming a spin-zero component and finding no evidence for other wave contributions, based on CLEO-c data.

Contribution

The study provides the first model-independent measurements of helicity form factors in this decay channel, enhancing understanding of the decay dynamics.

Findings

Confirmed the spin-zero K- pi+ component interferes with K*0bar amplitude.

Found no evidence for additional d- or f-wave contributions.

Provided precise form factor measurements from 2800 reconstructed decays.

Abstract

We present model independent measurements of the helicity basis form factors in the decay D+ -> K- pi+ e+ nu_e obtained from about 2800 decays reconstructed from a 281 pb^{-1} data sample collected at the psi(3770) center-of-mass energy with the CLEO-c detector. We confirm the existence of a previously observed spin-zero K- pi+ component interfering with the K*0bar amplitude. We see no evidence for additional d- or f-wave contributions.