2024/01/06 by Yuanxin Zheng, Zheng, Yuanxin, Zu-Xin Cai +9
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Nuclear physics research studies #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2401.03219
openalex publication_date 2024/01/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The Belle collaboration recently reported a promising candidate for the spin-2 D^*D^* partner of the X(3872), called the X2 for short, having a mass of (4014.3 ± 4.0 ± 1.5)~MeV and a width of (4 ± 11 ± 6)~MeV . Assuming the X2 as a pure molecule of the D^*D^*, we calculated in detail the hidden charmonium decays of the X2 → J/ψV and X2→ηcP via the intermediate meson loops, where V = ρ0 ,ω and P= π0 ,η ,η'. The results indicate that the decay widths are strongly dependent on the X2 mass. At present center value of the mass 4014.3~MeV, the width for the X2→ J/ψρ0 is predicted to be a few tens of keV, while it is on the order of 102-3~keV for the X2→ J/ ψω; the predicted width for the X2→ ηc π0 is about a few keV, while the widths for X2→ηcη and ηcη' are around a few tens and tenths of keV, respectively. We also investigated the dependence of the ratios between these widths on the X2 mass and on the η-η' mixing angle, which may be good quantities for experiments. We hope that the present calculations would be checked experimentally in the future.