Probing scalar mesons in semi-leptonic decays of $D_s^+$, $D^+$ and $D^0$

TL;DR

This paper uses a generalized linear sigma model to analyze semi-leptonic decays of D mesons, aiming to understand the quark substructure of scalar mesons and testing the model's predictions against experimental data.

Contribution

The study applies a previously fitted linear sigma model to new D meson decay channels, extending its validation for scalar meson substructure analysis.

Findings

Model predictions agree reasonably with experimental results.

The approach supports the quark substructure hypothesis of scalar mesons.

The model successfully describes multiple semi-leptonic decay channels.

Abstract

With the primary motivation of probing the quark substructure of scalar mesons, a generalized linear sigma model for the lowest and the next-to-lowest scalar and pseudoscalar mesons is employed to investigate several semi-leptonic decays of $D$ mesons. The free parameters of the model (in its leading approximation) have been previously determined from fits to mass spectra and various low-energy parameters. With these fixed parameters, the model has already given encouraging predictions for different low-energy decays and scattering, as well as for semileptonic decay channels of $D_s^+$ that include a scalar meson in the final state. In the present work, we apply the same model (in its leading order with the same fixed parameters) to different semi-leptonic decay channels of $D_s^+$, $D^+$ and $D^0$ and thereby further test the model and its predictions for the quark substructure of scalar mesons. We find that these predictions are in reasonable agreement with experiment.