Standart model ötesinde b bozunumlarında cp-bozulumu

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Tezin Türü: Doktora

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Fizik Bölümü, Türkiye

Tezin Onay Tarihi: 2005

Tezin Dili: İngilizce

Öğrenci: Valı Bashiry

Danışman: TAHMASIB ALIYEV

Özet:

In this thesis, using a general model independent form of the effective Hamiltonian, the CP-violating asymmetries in the b -> d l l transition, when one of the leptons is polarized, is investigated. The sensitivity of the CP-violating asymmetries on the new Wilson coefficients are analyzed. Next, in the frame work of the same formalism, the polarized lepton pair forwardاbackward asymmetries in B->K l l decay are studied. We present the general expression for the nine doubleاpolarization forwardاbackward asymmetries. It is obtained that, the zero point position of the forwardاbackward asymmetries of the doublyاpolarized lepton pair does not depend on long distance effects but depends on short distance dynamics. Furthermore, it is shown that the zero position of AFB is very sensitive to the sign of the new Wilson coefficients. When sign of the Wilson coefficients is positive (negative) the zero position of the forwardاbackward asymmetries shifts to the left(right) compared to the SM. Moreover, the dependencies of the nine doubleاpolarization forwardا backward asymmetries on new Wilson coefficients, and the correlation of the averaged nine doubleاpolarization forwardاbackward asymmetries with branching ratio, have been studied. It is observed that, the study of the nine doubleاpolarization forwardاbackward asymmetries can serve as a good test in establishing new physics beyond the Standard Model. Finally, we observed that there are exist such regions of new Wilson coefficients for which the nine doubleاpolarization forwardاbackward asymmetries considerably depart from the SM result, while the branching ratio coincides with that of the SM prediction. In other words, new physics effects can be established by analyzing polarized forwardbackward asymmetry in this region of the new Wilson coefficients.