Sequential decays of the. Upsilon. prime prime

Journal Article · Mon Mar 25 04:00:00 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]

---

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

Related Subjects

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