arXiv subjects
Publications and source records attributed to A. Ozpineci.
We present the explicit form of the expressions of the 'Lambda' baryon polarizations in (Lambda_b -> Lambda l^+ l^-) decay for the massive lepton case as a complementary to our previous work prep: hep--ph/0211447.
We present the model independent analysis of $Λ$ baryon polarizations in the (Lambda_b -> Lambda l^+ l^-) decay. The sensitivity of the averaged 'Lambda' polarizations to the new Wilson coefficients is studied. It is observed that there exist certain regions of the new Wilson coefficients where the branching ratio coincides with the standard model prediction, while the 'Lambda' baryon polarizations deviate from the standard model results remarkably.
The coupling constant of rho --> eta gamma decay is calculated in the framework of light cone QCD sum rules. A comparison of our prediction on the coupling constant with the result obtained from analysis of the experimental data is performed.
T--odd correlations as physical observables in the $B \rar K^\ast \ell^+ \ell^-$ decay have been studied using the most general form of the effective Hamiltonian. It is observed that these quantities are very sensitive to the new physics. We estimate the potential of discovery of these quantities at future hadron colliders.
We study semileptonic decay B --> eta l nu. The transition form factors for this decays are calculated by using light cone QCD sum rules.
Using the most general, model independent form of effective Hamiltonian, the transverse polarization P_T of Lambda in Lambda_b -> Lambda l^+ l^- decay is studied. It is observed that the averaged is very sensitive to the existence of new physics and can attain large values, which can be measured at future colliders.
Octet baryon magnetic moments are calculated in framework of the light cone QCD sum rules. The analysis is carried for the general form of the interpolating currents for octet baryons. A comparison of our results on the magnetic moments of octet baryons with the predictions of other approaches and experimental data is presented.
We study lepton polarization asymmetries in the (Lambda_b -> Lambda l^+ l^-) decay using the most general model independent effective Hamiltonian. The dependence of the lepton polarizations and their combinations on the new Wilson coefficients are studied in detail. It is observed that there is a region for the new Wilson coefficients for which the branching ratio coincides with the standard model prediction, while lepton polarizations show considerable departure from standard model.
Using the most general, model independent form of the effective Hamiltonian, the exclusive, rare baryonic (Lambda_b -> Lambda l^+ l^- ~l=μ,τ) decay is analyzed. We study sensitivity of the branching ratio and lepton forward-backward asymmetry to the new Wilson coefficients. Is is shown that these physical quantities are quite sensitive to the new Wilson coefficients. Determination of the position of zero value of the forward-backward asymmetry can serve as a useful tool for establishing new physics beyond the standard model, as well as fixing the sign of the new Wilson coefficients.
Using the most general, model independent form of the effective Hamiltonian rare decays (B -> l^+ l^- gamma (l=mu, tau)) are studied. The sensitivity of the photon energy distribution and branching ratio to the new Wilson coefficients is investigated.
Using the most general, model independent effective Hamiltonian, the branching ratio of the (B -> K^* l^+ l^-) decay, when K^* meson is longitudinally or transversally polarized, is presented. The dependence of the branching ratio on the new Wilson coefficients, when K^* meson is polarized, is studied. It is observed that the branching ratio is very sensitive to the vector and tensor type interactions, which will be useful in search of new physics beyond the Standard Model.
Using the general, model independent form of the effective Hamiltonian, the general expressions of the longitudinal, normal and transversal polarization asymmetries for (l^-) and (l^+) and combinations of them for the exclusive (B -> K l^+ l^-) decay are found. The sensitivity of lepton polarizations and their combinations on new Wilson coefficients are studied. It is found that there exist regions of Wilson coefficients for which the branching ratio coincides with the Standard Model result while the lepton polarizations differ substantially from the standard model prediction. Hence, studying lepton polarization in these regions of new Wilson coefficients can serve as a promising tool for establishing new physics beyond the Standard Model.
Using the general, model independent form of effective Hamiltonian, the decay spectrum of B^0 -> pi^+ pi^- l^+ l^- decay is studied. The sensitivity of experimentally measurable asymmetries to the new Wilson coefficients and time is studied. It is observed that different asymmetries are sensitive to the new Wilson coefficients and they can serve as an efficient tool for establishing new physics beyond SM.
Using the most general, model-independent form of effective Hamiltonian, the exclusive, rare $B \rar K^\ast ν\bar ν$ decay is analyzed. The sensitivity of the branching ratios and missing mass-squared spectrum to the new Wilson coefficients is discussed.
We calculate the magnetic moments of Delta baryons within the framework of QCD sum rules. A comparison of our results on the magnetic moments of the Delta baryons with the predictions of different approaches is presented.
We calculate the magnetic moments of decuplet baryons containing strange quarks within the framework of light cone QCD sum rules taking into account the SU(3) flavor symmetry breaking effects. It is obtained that magnetic moments of the neutral $\sso$ and $\xis0$ baryons are mainly determined by the SU(3) breaking terms. A comparison of our results on the magnetic moments of the decuplet baryons with the predictions of other approaches is presented.
Influence of the fourth generation, if ever exists, on the experimentally measurable quantities such as invariant dilepton mass distribution, lepton forward-backward asymmetry, and the ratio (Gamma_L/Gamma_T) of the decay widths when K* meson is longitudinally and transversally polarized, is studied. Using the experimental results on the branching ratios for the (B -> X_s) gamma and semileptonic (B -> X_c l nu) decays, the two possible solutions of the 4x4 Cabibbo-Kobayashi-Maskawa factor (V_{t's} V_{t^'b}) are obtained as a function of the t'-quark mass. It is observed that the results for the above-mentioned physical quantities are essentially different from the standard model predictions only for one solution of the CKM factor. In this case the above-mentioned physical quantities can serve as efficient tools in search of the fourth generation. The other solution yields almost identical results with the SM.
Understanding mechanisms for energy dissipation from nanoparticles in contact with large samples is a central problem in describing friction microscopically. Calculation of the reduced density matrix appears to be the most suitable metho to study such systems that are coupled to a large environment. In this paper the time evolution of the reduced density matrix has been evaluated for an arbitrary system coupled to a heat reservoir. The formalism is then applied to study the vibrational relaxation following the stick-slip motion of a small adsorbate on a surface. The frequency dependence of the relaxation time is also determined.