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We have achieved the isovector and isoscalar tensor form factors of the N ( 1535 ) state in the framework of the light-cone QCD sum rule approach. In numerical computations, we have considered the most general forms of the interpolating current for the nucleon and the tensor current together with the distribution amplitudes of the N ( 1535 ) resonance. We have shown that the squared momentum transfer, Q 2 , dependence of N ( 1535 ) tensor form factors is characterized by a multipole fit function. Our results provide a perspective of the momentum dependence of the tensor form factors and can help to improve our understanding of the internal structure of nucleon states.

The transition form factors responsible for the radiative ΣQ→ΛQγ and ΞQ′→ΞQγ decays of the negative parity baryons are examined within light cone QCD sum rules. The decay widths of the radiative transitions are calculated using the obtained results of the form factors. A comparison of our predictions on decay widths with the corresponding widths of positive parity baryons is given.

The magnetic moment of the Λ → Σ 0 transition between negative parity baryons is calculated in framework of the QCD sum rules approach by using the general form of the interpolating currents. The pollution arising from the positive-to-positive, and positive-to-negative parity baryons is eliminated by constructing the sum rules for different Lorentz structures. A comparison of our result with the predictions of the results of other approaches for the positive parity baryons is presented.

This study presents the analysis of form factor calculations of semileptonic transitions of heavy baryons via light cone QCD sum rules. The work covers the semileptonic transitions of the Ξ b and Ξ c baryons. The form factors for the transitions Ξ b → Ξ l + l − and Ξ c → Ξ l ν are obtained using their currents in the most general form. The obtained form factors are also used to calculate the decay widths and branching ratios of the considered transitions.

In this article, we calculate the B → a 1 ( 1260 ) form-factors V 1 ( q 2 ) , V 2 ( q 2 ) , V 3 ( q 2 ) and A ( q 2 ) with the B -meson light-cone QCD sum rules. Those form-factors are basic parameters in studying the exclusive non-leptonic two-body decays B → A P and semi-leptonic decays B → A l ν l , B → A l ¯ l . Our numerical results are consistent with the values from the (light-cone) QCD sum rules. The main uncertainty comes from the parameter ω 0 (or λ B ), which determines the shapes of the two-particle and three-particle light-cone distribution amplitudes of the B -meson, it is of great importance to refine this parameter.

In this article, we study the vertices D ∗ D ∗ P , D ∗ D V and DDV with the light-cone QCD sum rules. The strong coupling constants g D ∗ D ∗ P , g D ∗ D P , f D ∗ D V , f D ∗ D ∗ V , g D D V and g D ∗ D ∗ V play an important role in understanding the final-state interactions in the hadronic B decays. They relate to the basic parameters g, λ and β in the heavy quark effective Lagrangian respectively. Our numerical values of the g, β and λ are much smaller than most of the existing estimations. If the predictions from the light-cone QCD sum rules are robust, the final-state interaction effects maybe overestimated in the hadronic B decays.

We describe a light-cone QCD sum rule calculation of the $B_s\to f_0(980)$ transition form factors useful to predict the branching ratios of the rare decays $B_s \to f_0 \ell^+ \ell^-$, $B_s \to f_0 \nu \bar \nu$ and of $B_s\to J/\psi f_0$ decay assuming factorization. We compare this channel to $B_s \to J/\psi \phi$ as far as the possibility to determine the $B_s$ mixing phase is concerned.

The electric quadrupole and magnetic octupole moments of the light decuplet baryons are calculated in the framework of the light cone QCD sum rules. The obtained non-vanishing values for the electric quadrupole and magnetic octupole moments of these baryons show nonspherical charge distribution. The sign of electric quadrupole moment is positive for $\Omega^-$, $\Xi^{*-}$, $\Sigma^{*-}$ and negative for $\Sigma^{*+}$, which correspond to the prolate and oblate charge distributions, respectively. A comparison of the obtained results with the predictions of non-covariant quark model which shows a good consistency between two approaches is also presented. Comparison of the obtained results on the multipole moments of the decuplet baryons containing strange quark with those of $\Delta$ baryons shows a large SU(3) flavor symmetry breaking., Comment: 11 Pages and 1 Table

Inspired by the results of recent experimental discoveries for charm and bottom baryons, the masses and magnetic moments of the heavy baryons with J P = 3 / 2 + containing a single heavy quark are studied within light cone QCD sum rules method. Our results on the masses of heavy baryons are in good agreement with predictions of other approaches, as well as with the existing experimental values. Our predictions on the masses of the states, which are not yet discovered in the experiments, can be tested in the future experiments. A comparison of our results on the magnetic moments of these baryons and the hyper central model predictions is presented.

The axial N − Δ ( 1232 ) transition form factors are calculated within the light cone QCD sum rules method. A comparison of our results with the predictions of lattice theory and quark model is presented.

We investigate f_0-sigma mixing in the framework of light cone QCD sum rules and by employing the experimental results about the decay widths and the masses of these scalar mesons we estimate the scalar mixing angle by using sigma meson data and f_0 meson data. The two values we thus obtain of the scalar mixing angle are not entirely consistent with each other, possibly indicating that the structure of these mesons cannot be simple quark-antiquark states., 10 pages, Latex, 2 figures

The light cone QCD sum rules method is used to calculate the transition form factor for the radiative (phi -> f_0 gamma) decay, assuming that the quark content of the (f_0) meson is pure (bar{s}s) state. The branching ratio is estimated to be Br(phi -> f_0 gamma) = 3.5 x (1 pm 0.3) x 10^(-4). A comparison of our prediction on branching ratio with the theoretical results and experimental data existing in literature is presented., Comment: 8 pp, 1 figure (postscript formatted), LaTex formatted

We study $\phi a_0\gamma$- and $\phi\sigma\gamma$-vertices in the framework of the light cone QCD sum rules and we estimate the coupling constants g$_{\phi a_0\gamma}$ and g$_{\phi\sigma\gamma}$ utilizing $\omega\phi$-mixing. We compare our results with the previous estimations of these coupling constants in the literature obtained from phenomenological considerations.

Using the general form of the Σ 0 and Λ currents, the Σ 0 Λ transition magnetic moment is calculated in framework of the light cone QCD sum rules. A comparison of our result on this quantity with the existing theoretical results and experimental data is presented.

The radiative B c →l ν γ decay is investigated in the Standard Model in framework of the light cone QCD. The transition form factors and decay width are calculated. A comparison of light cone QCD and constituent quark model predictions on these quantities is presented.

The couplings of pions with heavy baryons g_2 (\Sigma^*, \Sigma) and g_3(\Sigma^*, \Lambda) are studied with light-cone QCD sum rules in the leading order of heavy quark effective theory. Both sum rules are stable. Our results are g_2=(1.56\pm 0.3), g_3=(0.94\pm 0.06)., Comment: Minor changes, typos corrected, final version to appear in Phys. Lett. B

The formfactors of B_1 -> pi and D_1 -> pi transitions, where B_1(D_1) is the 1^+ P-wave -> Q gamma_����_5q meson state, are calculated in the framework of the light cone QCD. Furthermore these formfactors are compared with the pole dominance model prediction using the values of the strong coupling constants g_{B_1 B^* pi} and g_{D_1 D^* pi}, and a good agreement between these two different descriptions is observed., 14 pages, 2 figures, LaTeX formatted. METU-PHYS-HEP-96-22

Using the light cone QCD Sum Rules Method, we study the rare B → ν ν γ decay and find that the branching ratios are, B(B s → ν ν γ) ⋍ 7.5 × 10 −8 , B(B d → ν ν γ) ⋍ 4.2 × 10 −9 . A comparison of our results on branching ratio with constituent quark and pole dominance model predictions are presented.

We calculate to the leading twist 2 accuracy the rate for the decay $ B_{u} \rightarrow l \nu \gamma $ using the light cone QCD sume rules. We find $ Br( B_{u} \rightarrow l \nu \gamma) \simeq 2 \cdot 10^{-6} $. The results are used to test the applicability of the constituent quark model approximation to the same process.The latter estimate is proportional to $ 1/m_{u}^{2} $, where $ m_{u} \simeq \bar{\Lambda}_{u} $ is the "constituent quark mass", indicating that the process is of long distance type. We find that the two approaches yield similar results for the rate with the choice $ m_{u} \simeq 430-480 \;MeV $. This indicates that the constituent quark model may be used for estimates of the radiative "annihilation" contribution to this and other radiative decays. We point out that this decay may be useful for the measurement of $ |V_{ub}|$.

The decay width, forward-backward asymmetry and lepton longitudinal and transversal polarization for the exclusive K^* -> l^+ l^- decay in a two Higgs doublet model are computed. It is shown that all these quantities are very effective tools for establishing new physics.

We propose a simple method to calculate the pion form factor at not very large momentum transfers, which combines the technique of the QCD sum rules with the description of the pion in terms of the set of wave functions of increasing twist. This approach allows one to calculate the soft (end point) contribution to the form factor in a largely model-independent way. Our results confirm existing expectations that the soft contribution remains important at least up to the momentum transfers of order 10 GeV$^2$, and suggest that it comes from the region of relatively small transverse separations of order 1 GeV$^{-1}$., LATEX, 11 pages, 3 figures appended as uu-encoded file, MPI-PhT/94-8

The radiative decays of decuplet to octet baryons are analyzed within the light cone QCD sum rules framework. The electromagnetic transition form factors for these decays are calculated at q(2) = 0 up to twist-4 accuracy for photon wave functions and including first order strange quark mass corrections. A comparison of our results with predictions of lattice theory and existing experimental data is presented. (c) 2005 Published by Elsevier B.V.