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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: 27Citation - 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: 4Citation - 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: 15Citation - Scopus: 15Strong Σbn B and Σcn D Coupling Constants in Qcd(Elsevier, 2015) Azizi, K.; Sarac, Y.; Sundu, H.We study the strong interactions among the heavy bottom spin-1/2 Sigma(b) baryon, nucleon and B meson as well as the heavy charmed spin-1/2 Sigma(c) baryon, nucleon and D meson in the context of QCD sum rules. We calculate the corresponding strong coupling form factors defining these vertices by using a three point correlation function. We obtain the numerical values of the corresponding strong coupling constants via the most prominent structure entering the calculations. (C) 2015 Elsevier B.V. All rights reserved.Article Citation - WoS: 12Citation - Scopus: 12Investigation of a Candidate Spin-1/2 Hidden-Charm Triple Strange Pentaquark State pcsss<(Amer Physical Soc, 2023) Azizi, K.; Sarac, Y.; Sundu, H.A candidate triple strange pentaquark state, P-csss, is investigated through its strong decay channel P-csss -> C2-J=y/. To calculate the relevant strong coupling constants, two possible interpolating currents with spin-parity JP 1/4 1 - are used. Though the chosen currents for the state under consideration have spin-parity quantum numbers JP 1/4 1 -, they couple to both the positive and negative parity states simultaneously and the corresponding decay widths are obtained for both parities. These widths are obtained as foP(csss) -> J=y/C2- +/_ 1/4 201.4 82.5 MeV for the negative and fo P similar to csss -> J=y/C2- +/_ 1/4 316.4 107.8 MeV for the positive parity state when the first current is used. For the second current, we obtain foP(csss) -> J=y/C2- +/_ 1/4 252.5 116.7 MeV for the negative and fo P similar to csss -> J=y/C2- +/_ 1/4 361.1 ; 98.4 MeV for the positive parity state. These results may provide insights into future experimental observations of such candidate states and help to distinguish and fix their properties.Article Citation - WoS: 12Citation - Scopus: 11Determination of the Possible Quantum Numbers for the Newly Observed Ξb< State(Springer, 2021) Azizi, K.; Sarac, Y.; Sundu, H.The LHCb Collaboration recently reported the observation of a new excited bottom baryon Xi(b)(6227)(0) and announced an improvement in the measurements related to the previously observed Xi(b)(6227)(-) state. We conduct an analysis for Xi(b)(6227)(0) state considering it as isospin partner of the Xi(b)(6227)(-) resonance and possibly 1P or 2S excited state with spin J = 3/2. The corresponding masses for both possibilities have consistent results with the experimental data, indicating that only with the mass sum rules, one can not make exact decision on the nature and quantum numbers of this state. To go further, the decays of these possible excited states to Xi(-)(b)pi(+) final state are also considered and the relevant strong coupling constants are extracted from the light cone sum rules. The obtained decay width values support the possibility of Xi(b)(6227)(0) to be the 1P excited state of Xi(b)(5945)(0) baryon.Conference Object Citation - WoS: 1Citation - Scopus: 1Strong D*2(2460)0 → D+π- Transition in QCD(E D P Sciences, 2014) Sarac, Y.; Azizi, K.; Sundu, H.This work presents the analysis of the transition D*(2)(2460)(0) > D+pi(-). In the calculation three point QCD sum rules method is applied and the value of the coupling constant for the considered vertex is obtained as gD*(2) D pi = (12.72 +/- 3.56) GeV-1.The result of the calculation is also utilized in the decay width and branching ratio calculations of the considered transition.Article Citation - WoS: 7Citation - Scopus: 7Tree Level Semileptonic Σb To Nucleon Decay in Light Cone Qcd Sum Rules(Amer Physical Soc, 2009) Azizi, K.; Bayar, M.; Ozpineci, A.; Sarac, Y.Using the most general form of the interpolating current of the heavy spin 1/2, Sigma(b) baryon and distribution amplitudes of the nucleon, the transition form factors of the semileptonic Sigma(b) -> Nl nu decay are calculated in the framework of light-cone QCD sum rules. It is obtained that the form factors satisfy the heavy quark effective theory relations. The obtained results for the related form factors are used to estimate the decay rate of this transition.Article Citation - WoS: 29Citation - Scopus: 29Strong Decay of pc< (4380) Pentaquark in a Molecular Picture(Elsevier, 2018) Azizi, K.; Sarac, Y.; Sundu, H.There are different assumptions on the substructure of the pentaquarks P-c(4380) and P-c(4450), newly founded in J/psi N invariant mass by the LHCb Collaboration, giving consistent mass results with the experimental observations. The experimental data and recent theoretical studies on their mass suggest interpretation of these states as spin-3/2 negative-parity and spin-5/2 positive-parity pentaquarks, respectively. There may exist opposite-parity states corresponding to these particles, as well. Despite a lot of studies, however, the nature and internal organization of these pentaquarks in terms of quarks and gluons are not clear. To this end we need more theoretical investigations on other physical properties of these states. In this accordance, we study a strong and dominant decay of the P-c(4380) to J/psi and N in the framework of three point QCD sum rule method. An interpolating current in a molecular form is applied to calculate six strong coupling form factors defining the transitions of the positive and negative parity spin-3/2 pentaquark states. The values of the coupling constants are used in the calculation of the decay widths of these transitions. The obtained results are compared with the existing experimental data. (C) 2018 The Author(s). Published by Elsevier B.V.Article Citation - WoS: 43Citation - Scopus: 42Light Cone Qcd Sum Rules Study of the Semileptonic Heavy Ξq and Ξq′ Transitions To Ξ and Σ Baryons(Springer, 2012) Azizi, K.; Sarac, Y.; Sundu, H.The semileptonic decays of heavy spin-1/2, Xi(b(c)) and Xi(b(c))' baryons to the light spin-1/2, Xi and S baryons are investigated in the framework of light cone QCD sum rules. In particular, using the most general form of the interpolating currents for the heavy baryons as well as the distribution amplitudes of the Xi and Sigma baryons, we calculate all form factors entering the matrix elements of the corresponding effective Hamiltonians in full QCD. Having calculated the responsible form factors, we evaluate the decay rates and branching fractions of the related transitions.
