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Title: The lifetime probability tag measurement of R{sub b} using the SLD

Conference ·
OSTI ID:114004

The authors present a new measurement of R{sub b} = {Lambda}{sub Z{degree}{yields}b{anti b}}/{Lambda}{sub Z{degree}{yields}hadrons} using a lifetime double tag on 150k hadronic Z{degree} events collected from the SLD 1993 and 1994 runs. The method utilizes the high precision 3-D position measurements provided by the CCD vertex detector and the small stable SLC beams to obtain a b hemisphere tagging efficiency of 31% for a purity of 94%. The b-Hemisphere tagging efficiency is measured from the data reducing dependence on the B-decay model and detector simulation. They obtain a result of R{sub b} = 0.2171 {+-} 0.0040{sub statistical} {+-} 0.0037{sub systematic} {+-} 0.0023{sub R{sub c}}.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States); Boston Univ., MA (United States). Dept. of Physics; California Institute of Technology (CalTech), Pasadena, CA (United States); California Univ., Santa Barbara, CA (United States); California Univ., Santa Cruz, CA (United States); Colorado State Univ., Fort Collins, CO (United States); Colorado Univ., Boulder, CO (United States); Univ. of Illinois at Urbana-Champaign, IL (United States); Univ. of California, Berkeley, CA (United States); Massachusetts Univ., Amherst, MA (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Oregon Univ., Eugene, OR (United States). Inst. of Theoretical Science; Stanford Univ., CA (United States); Tennessee Univ., Knoxville, TN (United States); Wisconsin Univ., Madison, WI (United States). Dept. of Physics
Sponsoring Organization:
USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States); Science and Engineering Research Council, Swindon (United Kingdom); Istituto Nazionale di Fisica Nucleare, Rome (Italy); Japan-US Cooperative Research Project on High Energy Physics, Nagoya (Japan)
DOE Contract Number:
FG02-91ER40676; FG03-92ER40701; FG03-91ER40618; FG03-92ER40689; FG03-93ER40788; FG02-91ER40672; FG02-91ER40677; AC03-76SF00098; FG02-92ER40715; AC02-76ER03069; FG06-85ER40224; AC03-76SF00515; FG05-91ER40627; AC02-76ER00881; FG02-92ER40704
OSTI ID:
114004
Report Number(s):
SLAC-PUB-95-7004; CONF-950705-17; ON: DE96001023; CNN: Grant PHY-91-13428; Grant PHY-89-21320; Grant PHY-92-04239; Grant PHY-88-17930; Grant PHY-88-19316; Grant PHY-92-03212; TRN: 95:023238
Resource Relation:
Conference: HEP 95: international Europhysics conference on high-energy physics, Brussels (Belgium), 27 Jul - 2 Aug 1995; Other Information: PBD: Aug 1995
Country of Publication:
United States
Language:
English