Measurement Of Direct Cp Violation In B 2 Sc Bar C And B 2 D Barc C Quark Transitions Using B 2 J Psik And B 2 J Psi Pi Decays

Measurement of Direct CP Violation in B 2!sc$\bar{c}$ and B 2!d$\barc{c}$ Quark Transitions Using B+ 2!J/psiK+ and B+2!J/[Psi][pi]+ Decays

This thesis describes the measurement of the direct CP violation in the b → sc$\bar{c}$ transition using the decay B+ → J/[Psi]K+, and in the b → dc$\bar{c}$ transition using the decay B+ → J/[Psi][pi]+. The decays of B+ mesons are reconstructed in approximately 2.8 fb-1 of data recorded by D0 detector in 2002-2007 during Run II of Fermilab Tevatron collider. Using the unbinned likelihood fit, a signal of 40,222 ± 242 of B+ → J/[Psi]K+ and 1,578 ± 119 of B+ → J/[Psi][pi]+ events is obtained. The corresponding direct CP violation asymmetries are measured to be ACP(B+ → J/[Psi](1S)K+) = +0.0077 ± 0.0061(stat.) ± 0.0027(syst.), and ACP(B+ → J/[Psi](1S)[pi]+) = - 0.089 ± 0.081(stat.) ± 0.028(syst.). The result on ACP (B+ → J/[Psi](1S)K+) is consistent with the 2007 world average and is the most precise measurement of this asymmetry, with uncertainty approaching the level of the Standard Model prediction. The result on ACP (B+ → J/[Psi](1S)[pi]+) constitutes the first measurement of this asymmetry at the hadron collider, with uncertainty at the level of the 2007 world average. The measurement presented in this thesis has become possible due to the sophisticated online and offline tracking/vertexing implemented at D0, and the regular reversal of the polarities of the D0 detector magnets.

Measurement of Direct CP Violation in B {u2192} Sc$\bar{c}$ and B {u2192} D$\barc{c}$ Quark Transitions Using B+ {u2192} J/psiK+ and B+{u2192} J/??+ Decays

This thesis describes the measurement of the direct CP violation in the b → sc$ar{c}$ transition using the decay B+ → J/?K+, and in the b → dc$ar{c}$ transition using the decay B+ → J/??+. The decays of B+ mesons are reconstructed in approximately 2.8 fb-1 of data recorded by D0 detector in 2002-2007 during Run II of Fermilab Tevatron collider. Using the unbinned likelihood fit, a signal of 40,222 ± 242 of B+ → J/?K+ and 1,578 ± 119 of B+ → J/??+ events is obtained. The corresponding direct CP violation asymmetries are measured to be ACP(B+ → J/?(1S)K+) = +0.0077 ± 0.0061(stat.) ± 0.0027(syst.), and ACP(B+ → J/?(1S)?+) = - 0.089 ± 0.081(stat.) ± 0.028(syst.). The result on ACP (B+ → J/?(1S)K+) is consistent with the 2007 world average and is the most precise measurement of this asymmetry, with uncertainty approaching the level of the Standard Model prediction. The result on ACP (B+ → J/?(1S)?+) constitutes the first measurement of this asymmetry at the hadron collider, with uncertainty at the level of the 2007 world average. The measurement presented in this thesis has become possible due to the sophisticated online and offline tracking/vertexing implemented at D0, and the regular reversal of the polarities of the D0 detector magnets.

Measurement of Direct CP Violation Parameters in $B\̂pm \to J/\psi K\̂pm$ and $B\̂pm \to J/\psi \pi\̂pm$ Decays with 10.4 Fb${̂-1}$ of Tevatron Data