540 research outputs found

    CP-Violation in B_{q} Decays and Final State Strong Phases

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    Using the unitarity, SU(2) and CC-invariance of hadronic interactions, the bounds on final state phases are derived. It is shown that values obtained for the final state phases relevant for the direct CP-asymmetries ACP(B0β†’K+Ο€βˆ’,K0Ο€0)A_{CP}(B^{0}\to K^{+}\pi ^{-},K^{0}\pi ^{0}) are compatiable with experimental values for these asymmetries. For the decays B0β†’D(βˆ—)βˆ’Ο€+B^{0}\to D^{(\ast)-}\pi ^{+} (D(βˆ—)+Ο€βˆ’)(D^{(\ast)+}\pi ^{-}) described by two independent single amplitudes AfA_{f} and AfΛ‰β€²A_{\bar{f}}^{\prime} with differnt weak phases (0 and Ξ³\gamma ) it is argued that the CC-invariance of hadronic interactions implies the equality of the final state phase Ξ΄f\delta_{f} and Ξ΄fΛ‰β€²\delta_{\bar{f}}^{\prime}. This in turn implies, the CP-asymmetry % \frac{S_{+}+S_{-}}{2} is determined by weak phase (2Ξ²+Ξ³)2\beta +\gamma) only whereas S+βˆ’Sβˆ’2=0.\frac{S_{+}-S_{-}}{2}=0. Assuming factorization for tree graphs, it is shown that the Bβ†’D(βˆ—)B\to D^{(\ast)} form factors are in excellent agreement with heavy quark effective theory. From the experimental value for (S++Sβˆ’2)Dβˆ—Ο€,(\frac{S_{+}+S_{-}}{2})_{D^{\ast}\pi}, the bound sin⁑(2Ξ²+Ξ³)β‰₯0.69% \sin (2\beta +\gamma)\geq 0.69 is obtained and (\frac{S_{+}+S_{-}}{2%}) _{D_{S}^{\ast -}K^{+}}\approx -(0.41\pm 0.08)\sin \gamma is predicted. For the decays described by the amplitudes Afβ‰ AfΛ‰A_{f}\neq A_{\bar{f}} such as B0⟢ρ+Ο€βˆ’:B^{0}\longrightarrow \rho ^{+}\pi ^{-}: AfΛ‰A_{\bar{f}} and B0βŸΆΟβˆ’Ο€+:Af% B^{0}\longrightarrow \rho ^{-}\pi ^{+}:A_{f} where these amplitudes are given by tree and penguin diagrams with differnt weak phases, it is shown that in the limit Ξ΄f,fΛ‰Tβ†’0,rf,fΛ‰cos⁑δf,fΛ‰=cos⁑α\delta_{f,\bar{f}}^{T}\to 0,r_{f,\bar{f}}\cos \delta_{f,\bar{f}}=\cos \alpha and SfΛ‰Sf=S=βˆ’1βˆ’CfΛ‰21βˆ’Cf2\frac{S_{\bar{f}}}{S_{f}}=\frac{% S+\Delta S}{S-\Delta S}=-\frac{\sqrt{1-C_{\bar{f}}^{2}}}{\sqrt{1-C_{f}^{2}}}% . Comment: 20 Pages, 1 Figure, Appeared in PR

    Final state phases in B -> D\pi, \bar{D}\pi decays and CP-asymmetry

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    Final state phases \delta_f and \delta_f' in B-> D pi, barD pi decays are shown to be equal i.e. \delta =\delta_f-\delta_f' = 0. Thus CP-violating asymmetry A(t) is independent of final state phases. The estimate for the phases \delta_f and \delta_f' is also given.Comment: 6 pages, no figur
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