Observation of the Singly Cabibbo-Suppressed Decay $D^{+}\to\omega\pi^{+}$ and Evidence for $D^{0}\to\omega\pi^{0}$

TL;DR

This study reports the first observation of the singly Cabibbo-suppressed decays D+→ωπ+ and evidence for D0→ωπ0 using BESIII data, measuring their branching fractions with high statistical significance.

Contribution

It provides the first measurements of these rare decay modes, expanding understanding of charm meson decay processes and testing theoretical models of weak interactions.

Findings

Branching fraction for D+→ωπ+ is (2.79±0.57±0.16)×10⁻⁴.

Branching fraction for D0→ωπ0 is (1.17±0.34±0.07)×10⁻⁴.

Statistical significances are 5.5σ and 4.1σ, respectively.

Abstract

Based on 2.93 fb$^{-1}$ $e^+e^-$ collision data taken at center-of-mass energy of 3.773 GeV by the BESIII detector, we report searches for the singly Cabibbo-suppressed decays $D^{+}\to\omega\pi^{+}$ and $D^{0}\to\omega\pi^{0}$. A double tag technique is used to measure the absolute branching fractions $\mathcal{B}(D^{+}\to\omega\pi^{+})=(2.79\pm0.57\pm0.16)\times 10^{-4}$ and $\mathcal{B}(D^{0}\to\omega\pi^{0})=(1.17\pm0.34\pm0.07)\times 10^{-4}$, with statistical significances of $5.5\sigma$ and $4.1\sigma$, respectively. We also present measurements of the absolute branching fractions for the related $\eta \pi$ decay modes. We find $\mathcal{B}(D^{+}\to\eta\pi^{+})=(3.07\pm0.22\pm0.13)\times10^{-3}$ and $\mathcal{B}(D^{0}\to\eta\pi^{0})=(0.65\pm0.09\pm0.04)\times10^{-3}$, which are consistent with the current world averages. The first and second uncertainties are statistical and systematic, respectively.