Studies of the Strong and Electroweak Interactions at the Z0 Pole [Thesis]
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
This thesis presents studies of the strong and electroweak forces, two of the fundamental interactions that govern the behaviour of matter at high energies. We have used the hadronic decays of Z0 bosons produced with the unique experimental apparatus of the e+e- Linear Collider at the Stanford Linear Accelerator Center (SLAC) and the SLAC Large Detector (SLD) for these measurements. Employing the precision tracking capabilities of the SLD, we isolated samples of Z0 events containing primarily the decays of the Z0 to a chosen quark type. With an inclusive selection technique, we have tested the flavor independence of the strong coupling, $$α_{s1}$$, by measuring the rates of multi-jet production in isolated samples of light (uds), c, and b quark events. We find: $$α^{uds}_s/α^{all}_s$$ = 0.987 ± 0.027(stat) ± 0.022(syst) ± 0.022(theory), $$α^c_s/α^{all}_s$$ = 1.012 ± 0.104(stat) ± 0.102(syst) ± 0.096(theory), $$α^b_s/α^{all}_s$$ = 1.026 ± 0.041(stat) ± 0.041(syst) ± 0.030(theory), which implies that the strong interaction is independent of quark flavor within our present experimental sensitivity. We have also measured the extent of parity-violation in the $$Z^0c\overline{c}$$ coupling, given by the parameter $$A^0_c$$ using a sample of fully and partially reconstructed D* and D+ meson decays and the longitudinal polarization of the SLC electron beam. This sample of charm quark events was derived with selection techniques based on their kinematic properties and decay topologies. We find $$A^0_c$$ = 0.73±0.22(stat)±0.10(syst). This value is consistent with that expected in the electroweak standard model of particle interactions.
- 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:
- 1454131
- Report Number(s):
- SLAC-R-458; TRN: US2310525
- Country of Publication:
- United States
- Language:
- English
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