Some problems in heavy-quarkonium decays

• Published in: Physics of atomic nuclei Vol. 78; no. 3; pp. 428 - 435
• Main Authors: Achasov, N. N., Kiselev, A. V., Kozhevnikov, A. A., Shestakov, G. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.05.2015; Springer
• Subjects: ANNIHILATION; BRANCHING RATIO; ELECTRON-POSITRON COLLISIONS; Elementary Particles and Fields; F0-980 MESONS; FORECASTING; GLUONS; INTERFERENCE; INTERMEDIATE STATE; MESON FACTORIES; Particle and Nuclear Physics; PARTICLE PRODUCTION; Physics; Physics and Astronomy; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; PSEUDOSCALAR MESONS; PSEUDOSCALARS; QUARKONIUM; RESONANCE PARTICLES; SEMILEPTONIC DECAY; UNITARITY; Atomic Nucleus; Decay Process; Branch Ratio; Semileptonic Decay; Resonance Region
• ISSN: 1063-7788; 1562-692X
• DOI: 10.1134/S1063778815020040

Problems proposed by the present authors for studies at c - τ , b , super- c - τ , and super- b factories are formulated. First, a comparison of the mechanisms of light-scalar-meson production in the process with the mechanisms of light-pseudoscalar-meson production in the process reveals that the transition is negligible in relation to the transition . As for f 0 (980), is not more than 30% of . It is proposed to study light scalar mesons in the semileptonic decays of D + ( D − ) , B + ( B − ), and . Second, interference phenomena observed in the ψ (3770)-resonance region in the reaction are described on the basis of models satisfying the elastic-unitarity requirement. As a model, we propose the model of mixed ψ (3770) and ψ (2 S ) resonances. In order to select theoretical models, it is proposed to employ non- decay channels such as e + e − → ψ (3770) → γχ c 0 , J / ψη , and ϕη . Third, branching ratios are calculated for ψ (3770) and ϒ(10580) decays proceeding to light (non- and non- ) hadrons owing to the contributions of real and intermediate states. The predictions obtained for these branching ratios lie in the range of 1% ≲ BR ≲ 15%. The lower boundary of this range is ten times higher than the branching ratio for annihilation to three gluons.