Measurement of the branching fraction of. Upsilon. 's yields. mu. mu

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5828197

Kaarsberg, T M

Results on the branching fraction of {Upsilon}'s {yields} {mu}{mu} from the Columbia-Stony Brook (CUSB) collaboration are presented. Using the upgraded CUSB-II detector at the Cornell electron storage ring (CESR), the branching fractions were measured to be B{sub {mu}{mu}} ({Upsilon}{double prime}) = (1.72 {+-} 0.15 {+-} 0.11)%, and B{sub {mu}{mu}} ({Upsilon}) = (2.61 {+-} 0.09 {+-} 0.11)%, where the first error is statistical and the second systematic. This is the first accurate B{sub {mu}{mu}} ({Upsilon}{double prime}) and now the most accurate B{sub {mu}{mu}} ({Upsilon}). This measurement of the {Upsilon}'s b{bar b} annihilation decay into two muons determines the {Upsilon}'s total widths, the strong coupling constant, {alpha}{sub s} and the QCD scale parameter {Lambda}{sub MS}. The values obtained are {Gamma}{sub tot}({Upsilon}{double prime}) = (24.1 {+-} 2.1 {+-} 2.4) keV, and {Gamma}{sub tot}({Upsilon}) = (51.0 {+-} 1.8 {+-} 2.0) keV; {alpha}{sub s} (4.97GeV) = 0.175{sup +0.005+0.003}{sub {minus}0.004-0.003} and {alpha}{sub s} (4.54GeV) = 0.175 {+-} 0.002 {+-} 0.003; {Lambda}{sub MS} = 162{sup +17+12}{sub {minus}14-10} MeV from the {Upsilon}{double prime} and {Lambda}{sub MS} = 149 {+-} 8 {+-} 11 MeV from the {Upsilon}.

• Research Organization: State Univ. of New York, Stony Brook, NY (USA)
• OSTI ID: 5828197
• Country of Publication: United States
• Language: English

Related Subjects

645102* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Weak Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANNIHILATION
BASIC INTERACTIONS
BOSONS
BOTTOMONIUM
BRANCHING RATIO
CESR STORAGE RING
COUPLING CONSTANTS
DATA
DECAY
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FERMIONS
HADRONS
INFORMATION
INTERACTIONS
LEPTONIC DECAY
LEPTONS
MESONS
MUONS
NUMERICAL DATA
PARTICLE DECAY
QUARKONIUM
STORAGE RINGS
VECTOR MESONS
WEAK INTERACTIONS
WEAK PARTICLE DECAY