Measurement Of The Cp Violation Parameter Sin 2 Beta

Measurement of the CP Violation Parameter Sin(2[beta] in B° 2!/[psi] K{sub S}° Decays

Measurement of the Cp Violation Parameter Sin 2 Beta

This thesis presents a measurement of the time-dependent asymmetry in the rate of {anti B}{sub d}° versus B{sub d}° decays to J/[psi]K{sub s}°. In the context of the Standard Model this is interpreted as a measurement of the CP violation parameter sin(2[beta]). A total of 198±17 B{sub d}°/{anti B}{sub d}° decays were observed in p{anti p} collisions at √s=1.8 TeV by the CDF detector at the Fermilab Tevatron. The initial B flavor (whether B° or {anti B}°) is determined by a same-side flavor tagging technique. The analysis results in sin(2[beta])=1.8±1.1(stat.)±0.3(syst.). This analysis demonstrates the feasibility of studying CP violation in the B°-{anti B}° system at a hadron collider. By applying the methods used in this analysis, future, higher-statistics experiments should be able to tightly constrain the parameters of the Standard Model.

Measurement of the CP Violation Parameter Sin(2[beta] in B[sup 0][r-arrow]J/[psi] K[sub S][sup 0] Decays

A sample of[approximately] 400 B[sub d][sup 0]/[bar B][sub d][sup 0][r-arrow] J/[psi]K[sub s][sup 0] decays collected in[bar p]p collisions by the CDF detector is used to directly measure the CP-violation parameter sin (2[beta]). They find sin(2[beta])= 0.79[sub[minus]0.44][sup+ 0.41], favoring the standard model expectation of a large CP violation in this B[sup 0] decay mode.