Analysis of the ψ ( 3770 ) resonance in line with unitarity and analyticity constraints

Hanhart, Christoph; Kürten, Stephan; Reboud, Méril; van Dyk, Danny

Abstract

We study the inclusive and exclusive cross sections of e+e-→hadrons for center-of-mass energies between 3.70 and 3.83GeV to infer the mass, width, and couplings of the ψ(3770) resonance. By using a coupled-channel K-matrix approach, we setup our analysis to respect unitarity and the analyticity properties of the underlying scattering amplitudes. We fit several models to the full dataset and identify our nominal results through a statistical model comparison. We find that, accounting for the interplay between the ψ(2S) and the ψ(3770), no further pole is required to describe the ψ(3770) line shape. In particular we derive from the pole location Mψ(3770)=3778.8±0.3MeV and Γψ(3770)=25.0±0.5MeV. Moreover, we find the decay to D+D- and D0D¯0 to be consistent with isospin symmetry and derive an upper bound on the branching ratio B(ψ(3770)→non-DD¯)<6% at 90% probability.

Citation

Hanhart, C., Kürten, S., Reboud, M., & van Dyk, D. (2024). Analysis of the ψ ( 3770 ) resonance in line with unitarity and analyticity constraints. The European Physical Journal C, 84(5), Article 483. https://doi.org/10.1140/epjc/s10052-024-12785-8

• Journal Article Type: Article
• Acceptance Date: Apr 8, 2024
• Online Publication Date: May 9, 2024
• Publication Date: May 9, 2024
• Deposit Date: May 14, 2024
• Publicly Available Date: May 14, 2024
• Journal: The European Physical Journal C
• Print ISSN: 1434-6044
• Publisher: SpringerOpen
• Peer Reviewed: Peer Reviewed
• Volume: 84
• Issue: 5
• Article Number: 483
• DOI: https://doi.org/10.1140/epjc/s10052-024-12785-8
• Public URL: https://durham-repository.worktribe.com/output/2437543