A preliminary measurement of the gluon splitting rate into bb̄ pairs in hadronic

We present a measurement of the rate of gluon splitting into bottom quarks, g → bb̄, in hadronic Z decays collected by SLD from 1996 to 1998. The analysis was performed by looking for secondary bottom production in 4-jet events of any primary flavor. A topological vertex mass technique was used to tag the two jets with the smallest angle between them as b/b̄. We obtained a rate of g → bb̄ per hadronic event to be (3.07±0.71(stat.)±0.66(syst.))× 10 (preliminary). Presented at the American Physical Society (APS) Meeting of the Division of Particles and Fields (DPF 99), 5-9 January 1999, University of California, Los Angeles ∗Work supported by Department of Energy contract DE–AC03–76SF00515 (SLAC).