Sequential decays of the. Upsilon. prime prime

Journal Article · Mon Mar 25 00:00:00 EST 1991 · Physical Review Letters; (USA)

DOI:https://doi.org/10.1103/PhysRevLett.66.1563· OSTI ID:5846968

Heintz, U; Kaarsberg, T; Lee-Franzini, J; Lovelock, D M.J.; Narain, M; Schamberger, R D; Willins, J; Yanagisawa, C ^[1]; Franzini, P; Tuts, P M; Kanekal, S; Wu, Q ^[2]

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1. Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794 (USA)
2. Columbia University, New York, New York 10027 (USA)

We have studied the decay chain {Upsilon}{prime}{prime}{r arrow}{chi}{sub {ital b}}{sup {prime}}({chi}{sub {ital b}}){gamma} {r arrow}{Upsilon}{prime}({Upsilon}){gamma}{gamma}{r arrow}{mu}{mu}({ital ee}){gamma}{gamma} with the CUSB II detector at the Cornell Electron Storage Ring. For a sample of 1.33{times}10{sup 6} {Upsilon}{prime}{prime}'s we find {approx}400 events. We measure branching ratios for {chi}{sub {ital b}{ital J}}{sup {prime}}{r arrow}{Upsilon}{prime}({Upsilon}){gamma} and, using calculated {ital E}1 rates, we derive total and hadronic widths of the {chi}{sub {ital b}}{sup {prime}} states. From these widths we obtain values of {alpha}{sub {ital s}} in the range between 0.13 and 0.21, in agreement with other determinations. We observe the suppressed decay {Upsilon}{prime}{prime}{r arrow}{chi}{sub {ital b}}{gamma}. The measured branching ratio suggests that relativistic effects are important. We also determine the branching ratios for {Upsilon}{prime}{prime}{r arrow}{Upsilon}{prime}{pi}{sup 0}{pi}{sup 0} to be (1.3{plus minus}0.4{plus minus}0.2)% and {Upsilon}{prime}{prime}{r arrow}{Upsilon}{pi}{sup 0}{pi}{sup 0} to be (1.8{plus minus}0.3{plus minus}0.2)%.

• OSTI ID: 5846968
• Journal Information: Physical Review Letters; (USA), Vol. 66:12; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
QUANTUM CHROMODYNAMICS
COUPLING CONSTANTS
QUARKONIUM
UPSILON-10355 MESONS
RADIATIVE DECAY
BRANCHING RATIO
CORNELL 10-GEV SYNCHROTRON
E1-TRANSITIONS
EXPERIMENTAL DATA
GAMMA SPECTRA
LEPTONS
LEVEL WIDTHS
PIONS NEUTRAL
ACCELERATORS
BOSONS
BOTTOMONIUM
CYCLIC ACCELERATORS
DATA
ELEMENTARY PARTICLES
ENERGY-LEVEL TRANSITIONS
FERMIONS
FIELD THEORIES
HADRONS
INFORMATION
MESONS
MULTIPOLE TRANSITIONS
NUMERICAL DATA
PIONS
PSEUDOSCALAR MESONS
QUANTUM FIELD THEORY
SPECTRA
SYNCHROTRONS
VECTOR MESONS
645101* - High Energy Physics- Particle Interactions & Properties-Experimental- Electromagnetic Interactions & Properties
645102 - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties