Study of hadronic transitions between {upsilon} states and observation of {upsilon}(4S){yields}{eta}{upsilon}(1S) decay

Journal Article · Mon Dec 01 00:00:00 EST 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.112002· OSTI ID:21250978

Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V ^[1]; Tico, J Garra; Grauges, E ^[2]; Lopez, L; Palano, A; Pappagallo, M ^[3]; Eigen, G; Stugu, B; Sun, L ^[4]; Abrams, G S; Battaglia, M; Brown, D N; Cahn, R N ^[5]

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1. Laboratoire de Physique des Particules, IN2P3-CNRS et Universite de Savoie, F-74941 Annecy-Le-Vieux (France)
2. Universitat de Barcelona, Facultat de Fisica, Departament ECM, E-08028 Barcelona (Spain)
3. INFN Sezione di Bari, I-70126 Bari (Italy)
4. University of Bergen, Institute of Physics, N-5007 Bergen (Norway)
5. Lawrence Berkeley National Laboratory and University of California, Berkeley, California 94720 (United States)

We present a study of hadronic transitions between {upsilon}(mS) (m=4, 3, 2) and {upsilon}(nS) (n=2, 1) resonances based on 347.5 fb{sup -1} of data taken with the BABAR detector at the PEP-II storage rings. We report the first observation of {upsilon}(4S){yields}{eta}{upsilon}(1S) decay with a branching fraction B({upsilon}(4S){yields}{eta}{upsilon}(1S))=(1.96{+-}0.06{sub stat}{+-}0.09{sub syst})x10{sup -4} and measure the ratio of partial widths {gamma}({upsilon}(4S){yields}{eta}{upsilon}(1S))/{gamma}({upsilon}(4S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(1S))=2.41{+-}0.40{sub stat}{+-}0.12{sub syst}. We set 90% CL upper limits on the ratios {gamma}({upsilon}(2S){yields}{eta}{upsilon}(1S))/{gamma}({upsilon}(2S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(1S))<5.2x10{sup -3} and {gamma}({upsilon}(3S){yields}{eta}{upsilon}(1S))/{gamma}({upsilon}(3S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(1S))<1.9x10{sup -2}. We also present new measurements of the ratios {gamma}({upsilon}(4S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(2S))/{gamma}({upsilon}(4S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(1S))=1.16{+-}0.16{sub stat}{+-}0.14{sub syst} and {gamma}({upsilon}(3S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(2S))/{gamma}({upsilon}(3S){yields}{pi}{sup +}{pi}{sup -}{upsilon}(1S))=0.577{+-}0.026{sub stat}{+-}0.060{sub syst}.

• OSTI ID: 21250978
• Journal Information: Physical Review. D, Particles Fields, Vol. 78, Issue 11; Other Information: DOI: 10.1103/PhysRevD.78.112002; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BRANCHING RATIO
ETA MESONS
GAMMA RADIATION
MESONS
PARTICLE DECAY
PHOTONS
PIONS MINUS
PIONS PLUS
RESONANCE
STORAGE RINGS