Improved measurement of the probability for gluon splitting into b anti-b in Z0 decays

We have measured gluon splitting into bottom quarks, g→b b ̄ , in hadronic Z 0 decays collected by SLD between 1996 and 1998. The analysis was performed by looking for secondary bottom production in 4-jet events of any primary flavor. 4-jet events were identified, and in each event a topological vertex-mass technique was applied to the two jets closest in angle in order to identify them as b or b ̄ jets. The upgraded CCD-based vertex detector gives very high B -tagging efficiency, especially for B hadrons with the low energies typical of this process. We measured the rate of g→b b ̄ production per hadronic event, g b b ̄ , to be (2.44±0.59(stat.)±0.34(syst.))×10 −3 .

electron positron: colliding beams
electron positron: annihilation
Z0: electroproduction
Z0: hadronic decay
jet: multiple production
final state: (4jet)
gluon: fragmentation
bottom: pair production
particle identification: flavor
SLD

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Figures(0)

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