The Isgur-Wise Function within a Modified Heavy-Light Chiral Quark Model

TL;DR

This paper presents a modified heavy-light chiral quark model that predicts the Isgur-Wise function with a slope near -1, aligning better with experimental data, by introducing a new mass parameter in the heavy quark propagator.

Contribution

The paper introduces an extended version of the heavy-light chiral quark model that improves the prediction of the Isgur-Wise function's slope by adding a new mass parameter.

Findings

Predicted slope of the Isgur-Wise function around -1

Better agreement with recent experimental measurements

Implications for B --> D D-bar decay modes

Abstract

We consider the Isgur-Wise function xi(omega) within a new modified version of a heavy-light chiral quark model. While early versions of such models gave too small absolute value of the slope, namely xi'(1) of about -0.4 to -0.3, we show how extended version(s) may lead to values around -1, in better agreement with recent measurements. This is obtained by introducing a new mass parameter in the heavy quark propagator. We also shortly comment on the consequences for the decay modes B --> D D-bar.