{upsilon}(4S,5S){yields}{upsilon}(1S){eta} transitions in the rescattering model and the new BABAR measurement

Journal Article · Wed Oct 01 04:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.074001· OSTI ID:21254270

Ce, Meng ^[1]; Kuangta, Chao ^[1]

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1. Department of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China)

The {eta} transitions of {upsilon}(4S,5S) into {upsilon}(1S,2S) are studied in the rescattering model by considering the final state interactions above the BB threshold. The width of the {eta} transition of {upsilon}(4S) into {upsilon}(1S) is found to be larger than that of the dipion transition, and the ratio of {gamma}({upsilon}(4S){yields}{upsilon}(1S){eta}) to {gamma}({upsilon}(4S){yields}{upsilon}(1S){pi}{sup +}{pi}{sup -}) is predicted to be R{sub 4}=1.8-4.5, which is about 2 orders of magnitude larger than the expectation of the conventional hadronic transition theory, and is supported by the new BABAR measurement. The widths of the {eta} transitions of {upsilon}(5S) are found to be sensitive to the coupling constants g{sub {upsilon}}{sub (5S)B{sup (*)}}{sub B{sup (*)}} due to a large cancellation between contributions from the BB, B*B+c.c., and B*B* channels, and only a rough estimate {gamma}({upsilon}(5S){yields}{upsilon}(1S,2S){eta})=10-200 KeV can be given. The widths of the {eta}{sup '} transitions of {upsilon}(4S,5S) are also discussed, and they could be much smaller than that of the corresponding {eta} transitions mainly due to the tiny phase space.

• OSTI ID: 21254270
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 78; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CANCELLATION
COUPLING CONSTANTS
ETA MESONS
FINAL-STATE INTERACTIONS
KEV RANGE
PARTICLE DECAY
PHASE SPACE
PIONS MINUS
PIONS PLUS
RESCATTERING
SIMULATION