A novel measurement of the strong-phase difference between D⁰→ K^-π⁺ and D⁰→ K^-π⁺ decays using C-even and C-odd quantum-correlated DD pairs

2025/06/09 by BESIII Collaboration, Ablikim, M., Achasov, M. N. +698
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex)

paper · doi:10.48550/arxiv.2506.07907

Abstract

A novel measurement technique of strong-phase differences between the decay amplitudes of D⁰ and D⁰ mesons is introduced which exploits quantum-correlated DD pairs produced by e⁺e^- collisions at energies above the ψ(3770) production threshold, where DD pairs are produced in both even and odd eigenstates of the charge-conjugation symmetry. Employing this technique, the first determination of a D⁰-D⁰ relative strong phase is reported with such data samples. The strong-phase difference between D⁰→ K^-π⁺ and D⁰→ K^-π⁺ decays, δ^D_Kπ, is measured to be δ^D_Kπ=(192.8^{+11.0 + 1.9}_{-12.4 -2.4})^∘, using a dataset corresponding to an integrated luminosity of 7.13 fb^-1 collected at center-of-mass energies between 4.13-4.23 GeV by the BESIII experiment.

Citations

• First observation of quantum correlations in e⁺e^-→ XDD and C-even constrained DD pairs
• The Precision Monte Carlo Event Generator KK For Two-Fermion Final States In e+e- Collisions
• Photos — a universal Monte Carlo for QED radiative corrections in decays
• On Estimation of a Probability Density Function and Mode

Related

• Model-independent determination of the strong-phase difference between D⁰ and D⁰ → π⁺π^-π⁺π^- decays
• Updated model-independent measurement of the strong-phase differences between D⁰ and D⁰ → K⁰_S/Lπ⁺π^- decays
• Measurement of the strong-phase difference between D⁰ and D⁰→ K⁺K^-π⁺π^- in bins of phase space
• Quantum-correlated measurements of D⁰ → K⁰_{\rm S}π⁺π^-π⁰ and consequences for the determination of γ
• First observation of quantum correlations in e⁺e^-→ XDD and C-even constrained DD pairs