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Article Citation - WoS: 32Citation - Scopus: 34Semileptonic Λb,c To Nucleon Transitions in Full Qcd at Light Cone(Amer Physical Soc, 2009) Azizi, K.; Bayar, M.; Sarac, Y.; Sundu, H.The tree-level semileptonic Lambda(b)-> pl nu and Lambda(c)-> nl nu transitions are investigated using the light cone QCD sum rules approach in full theory. The spin 1/2, Lambda(Q) baryon with Q=b or c, is considered by the most general form of its interpolating current. The time ordering product of the initial and transition currents is expanded in terms of the nucleon distribution amplitudes with different twists. Considering two sets of independent input parameters entering to the nucleon wave functions, namely, QCD sum rules and lattice QCD parameters, the related form factors and their heavy quark effective theory limits are calculated and compared with the existing predictions of other approaches. It is shown that our results satisfy the heavy quark symmetry relations for lattice input parameters and b case exactly and the maximum violation is for charm case and QCD sum rules input parameters. The obtained form factors are used to compute the transition rates both in full theory and heavy quark effective theory. A comparison of the results on decay rate of Lambda(b)-> pl nu with those predicted by other phenomenological methods or the same method in heavy quark effective theory with different interpolating current and distribution amplitudes of the Lambda(b) is also presented.Article Citation - WoS: 28Citation - Scopus: 27Lepton Flavor Universality Violation in Semileptonic Tree Level Weak Transitions(Amer Physical Soc, 2019) Azizi, K.; Sarac, Y.; Sundu, H.The recent deviations of the experimental data on some parameters of the tree-level semileptonic B and B-c mesons decays from the standard model (SM) predictions indicate considerable violations of the lepton flavor universality, and as a result possible new physics (NP) effects. To better understand the possible NP effects it is necessary to study deeply the physical quantities defining these decays from many aspects. The calculations of the physical quantities require the determinations of the hadronic form factors entering the matrix elements of the considered transitions as the main inputs. We calculate the form factors governing the tree-level B-c -> J/psi l nu and B-c -> eta(c)l nu transitions within the QCD sum rules method. The obtained form factors are used in the calculations of the branching ratios (BRs) of the B-c -> J/psi l nu and B-c -> eta(c)l nu transitions as well as R(J/psi) and R(eta(c)). Our result on R(J/psi) supports the present tension between the SM theory prediction and the experimental data. Our result on R(eta(c)) can be checked in future experiments.Article Citation - WoS: 31Citation - Scopus: 30Structure of the Ξb< Resonance(Amer Physical Soc, 2018) Aliev, T. M.; Azizi, K.; Sarac, Y.; Sundu, H.We explore the recently observed Xi(b)(6227)(-) resonance to fix its quantum numbers. To this end, we consider various possible scenarios: It can be considered as either a 1P or 2S excitation of the Xi(b) and Xi'(b)(5935) ground-state baryons with spin-1/2 or the 1P or 2S excitation of the ground-state Xi(b)(5955) with spin-3/2. We calculate the masses of the possible angular-orbital 1P and 2S excited states corresponding to each channel employing the QCD sum rule technique. It is seen that all the obtained masses are in agreement with the experimentally observed value, implying that the mass calculations are not enough to determine the quantum numbers of the state under question. Therefore, we extend the analysis to investigate the possible decays of the excited states into Lambda K-b(0)- and Xi(-)(b) pi. Using the light cone QCD sum rule method, we calculate the corresponding strong coupling constants, which are used to extract the decay widths of the modes under consideration. Our results on decay widths indicate that the Xi(b)(6227)(-) is a 1P angular-orbital excited state of the Xi(b)(5955) baryon with quantum numbers J(P) = 3/2(-).Article Κk+π-< Vertex in Light Cone Qcd Sum Rules(Amer Physical Soc, 2010) Baytemir, G.; Sarac, Y.; Yilmaz, O.In this work we study the kappa K+pi(-) vertex in the framework of light cone QCD sum rules. We predict the coupling constant g kappa K+pi(-) to be g kappa K+pi(-) = (6.0 +/- 1.0) GeV and estimate the scalar f(0) - sigma mixing angle from the experimental ratio g(2)(kappa -> K pi)/g(2)(sigma -> pi pi).Article Citation - WoS: 1Citation - Scopus: 1κK*0γ-vertex in light cone QCD sum rules(Amer Physical Soc, 2008) Gokalp, A.; Sarac, Y.; Yilmaz, O.We investigate the kappa K*(0)gamma-vertex in the framework of light cone QCD sum rules. We estimate the coupling constant g(kappa K)*(0)gamma, and compare our result with that used in the nonlinear chiral Lagrangian approach using the vector-meson dominance model in the SU(3) limit.Article Citation - WoS: 5Citation - Scopus: 4Investigation of the bc< → Χc2< Bar-< Transition Via Qcd Sum Rules(Springer, 2013) Azizi, K.; Sarac, Y.; Sundu, H.We calculate the transition form factors of the semileptonic in the framework of QCD sum rules taking into account the two-gluon condensate corrections. Using the obtained results of form factors we estimate the decay widths and branching ratios related to this transition at all lepton channels. A comparison of the obtained results with the predictions of other non-perturbative approaches are also made. The orders of branching ratios for different lepton channels indicate that the transition can be studied at LHC using the collected or future data.Article Citation - WoS: 5Citation - Scopus: 3Investigation of Λ (1405)as a molecular pentaquark state(Springer, 2024) Azizi, K.; Sarac, Y.; Sundu, H.Lambda ( 1405 ) is one of the interesting particles with its unclear structure and distinct properties. It has a light mass compared to its non-strange counterpart, despite the strange quark it carries. This situation puts the investigation of this resonance among the hot topics in hadron physics and collects attention to clarify its properties. In this study, we focus on the calculation of the mass and residue of the Lambda ( 1405 ) resonance within the framework of QCD sum rules. We assign a structure in the form of a molecular pentaquark composed from admixture of K - meson-neutron. Using an interpolating current in this form, the masses and the current coupling constant are attained as m = 1406 +/- 128 MeV and lambda = ( 3.35 +/- 0.35 ) x 10( - 5) GeV 6 for q and m = 1402 +/- 141 MeV and lambda = ( 4.08 +/- 1.08 ) x 10( - 5) GeV 6 for I Lorentz structures entering the calculations, respectively. The obtained mass values agree well with the experimental data supporting the plausibility of the considered structure.Article Citation - WoS: 20Citation - Scopus: 20Properties of the Pc(4312) pentaquark and its bottom partner(Iop Publishing Ltd, 2021) Azizi, K.; Sarac, Y.; Sundu, H.We present an analysis of the newly observed pentaquark P-c(4312)(+) to shed light on its quantum numbers. To do that, the QCD sum rules approach is used. The measured mass of this particle is close to the Sigma D-++(c)- threshold and has a small width, which supports the possibility of its being a molecular state. We consider an interpolating current in a molecular form and analyze both the positive and negative parity states with spin-. We also consider the bottom counterpart of the state with similar molecular form. Our mass result for the charm pentaquark state supports that the quantum numbers of the observed state are consistent with J(P) = 1/2(-).Article Citation - WoS: 19Citation - Scopus: 17Strong ΛbNB and ΛcND vertices(Amer Physical Soc, 2014) Azizi, K.; Sarac, Y.; Sundu, H.We investigate the strong vertices among the Lambda(b), nucleon, and B meson as well as the Lambda(c), nucleon, and D meson in QCD. In particular, we calculate the strong coupling constants g Lambda bNB and g Lambda cND for different Dirac structures entering the calculations. In the case of the Lambda cND vertex, we compare the result with the only existing prediction obtained at Q(2) = 0.Article Citation - WoS: 27Citation - Scopus: 28Nature of the Ω (2012) Through Its Strong Decays(Springer, 2018) Aliev, T. M.; Azizi, K.; Sarac, Y.; Sundu, H.We extend our previous analysis on the mass of the recently discovered Omega (2012) state by investigation of its strong decays and calculation of its width employing the method of light cone QCD sum rule. Considering two possibilities for the quantum numbers of Omega (2012) state, namely 1P orbital excitation with J(P) = 3/2(-) and 2S radial excitation with J(P) = 3/2(+), we obtain the strong coupling constants defining the Omega (1P/2S) -> Xi K decays. The results of the coupling constants are then used to calculate the decay width corresponding to each possibility. Comparison of the obtained results on the total widths in this work with the experimental value and taking into account the results of our previous mass prediction on the Omega (2012) state, we conclude that this state is 1P orbital excitation of the ground state Omega baryon, whose quantum numbers are J(P) = 3/2(-).
