Resonant Two-body D Decays

TL;DR

This paper calculates the impact of specific resonances on D meson decay amplitudes, revealing significant deviations from factorization and implications for D meson mixing and lifetime differences.

Contribution

It introduces a method to estimate resonance contributions to D decay amplitudes using the soft pion theorem, highlighting their substantial role.

Findings

$K^*(1430)$ resonance contributes about 30% of the decay amplitude.

Higher $K^*(1950)$ resonance accounts for approximately 70% of the amplitude.

Results suggest large deviations from factorization and enhanced $D^0-ar D^0$ mixing.

Abstract

The contribution of a $K^*(1430)$ $0^+$ resonance to $D^0\to K^-\pi^+$ is calculated by applying the soft pion theorem to $D^+ \to K^* \pi^+$, and is found to be about 30% of the measured amplitude and to be larger than the $\Delta I=3/2$ component of this amplitude. We estimate a 70% contribution to the total amplitude from a higher $K^*(1950)$ resonance. This implies large deviations from factorization in D decay amplitudes, a lifetime difference between D^0 and D^+, and an enhancement of $D^0-\bar D^0$ mixing due to SU(3) breaking.