Measurement of the Polarized Forward-Backward Asymmetry of B Quarks Using Momentum-Weighted Track Charge at SLD
- Stanford Univ., CA (United States)
This thesis presents a direct measurement of the parity-violating parameter Ab by analyzing the polarized forward-backward asymmetry of b quarks in e+e- → Z0 → $$b\overline{b}$$. Data were taken at the Stanford Linear Accelerator Center (SLAC), with the Stanford Large Detector (SLD), which records the products of e+e- interactions at a center of mass energy √s = 91.2 GeV/c2 at the SLAC Linear Collider (SLC). The SLC/SLD experimental apparatus provides a unique and ideal environment for measuring electroweak asymmetries. Heavy flavor decays of the Z0 were identified inclusively by taking advantage of the long lifetime of B hadrons, the small, stable SLC beam spot, and SLD`s precise tracking detectors. Two analysis techniques for measuring Ab are presented: a binned fit to the left-right forward-backwards asymmetry of tagged events signed with momentum-weighted track charge, and a self-calibrating maximum-likelihood technique using momentum-weighted charge from the two hemispheres in each tagged event. From our 1994-1995 sample of 3.6 pb-1, having a luminosity-weighted average e- polarization of 77.3%, and our 1993 sample of 1.8 pb-1, having a luminosity-weighted polarization of 63.1%, we obtain Ab = 0.848 ± 0.046(stat.) ± 0.050(syst.).
- Research Organization:
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- AC02-76SF00515
- OSTI ID:
- 1454147
- Report Number(s):
- SLAC-R--476; SLAC-R--95-476
- Country of Publication:
- United States
- Language:
- English
Similar Records
Measurement of the polarized forward-backward asymmetry of B quarks using momentum-weighted track charge at SLD [Thesis]
Measurement of the polarized forward-backward asymmetry of Z{sup 0} yields b{bar b} using a lifetime tag and momentum-weighted track charge
Measurement of the polarized forward-backward asymmetry of Z{sup 0} {yields} b{bar b} using a lifetime tag and momentum-weighted track charge
Thesis/Dissertation
·
Tue Oct 31 23:00:00 EST 1995
·
OSTI ID:206415
Measurement of the polarized forward-backward asymmetry of Z{sup 0} yields b{bar b} using a lifetime tag and momentum-weighted track charge
Conference
·
Tue Aug 01 00:00:00 EDT 1995
·
OSTI ID:382978
Measurement of the polarized forward-backward asymmetry of Z{sup 0} {yields} b{bar b} using a lifetime tag and momentum-weighted track charge
Conference
·
Tue Aug 01 00:00:00 EDT 1995
·
OSTI ID:148612