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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 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(-).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: 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: 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: 12Citation - Scopus: 12New Λb< State as a 2s Bottom Baryon(Amer Physical Soc, 2020) Azizi, K.; Sarac, Y.; Sundu, H.As a result of continuous developments, the recent experimental searches lead to the observations of new particles at different hadronic channels. Among these hadrons are the excited states of the heavy baryons containing single bottom or charmed quark in their valance quark content. The recently observed Lambda(b)(6072)(0) state is one of these baryons and possibly 2S radial excitation of the Lambda(b) state. Considering this information from the experiment, we conduct a QCD sum rule analysis on this state and calculate its mass and current coupling constant considering it as a 2S radially excited Lambda(b) resonance. For completeness, in the analyses, we also compute the mass and current coupling constant for the ground state Lambda(0)(b) and its first orbital excitation. We also consider the Lambda(+)(c) counterpart of each state and attain their mass, as well. The obtained results are consistent with the experimental data as well as existing theoretical predictions.Article Citation - WoS: 10Citation - Scopus: 9Analysis of the strong D2* (2460)0 → D+ π- and Ds2*(2573)+ → D+ K0 transitions via QCD sum rules(Springer, 2014) Azizi, K.; Sarac, Y.; Sundu, H.The strong D-2* (2460)(0) -> D+ pi(-) and D-s2* (2573)(+) -> D+ K-0 transitions are analyzed via three-point QCD sum rules. First we calculate the corresponding strong coupling constants g(D2)*D pi and g(Ds2)*DK. Then we use them to calculate the corresponding decay widths and branching ratios. Making use of the existing experimental data on the ratio of the decay width in the pseudoscalar D channel to that of the vector D* channel, finally, we estimate the decay width and branching ratio of the strong D-2(*) (2460)(0) -> D*(2010)(+)pi(-) transition.Article Citation - Scopus: 1Investigations of Λ States With Spin-Parity 3 ± 2(Amer Physical Soc, 2024) Azizi, K.; Sarac, Y.; Sundu, H.The present study provides spectroscopic investigations of spin-32 A baryons with both positive and negative parities. The analysis mainly focuses on three states, namely 1P, 2P, and 2S, and corresponding masses are calculated using the QCD sum rule method. To implement the method, we apply two types of interpolating currents with octet and singlet quantum numbers and compare the corresponding results with the reported masses of experimentally observed states. From the comparisons, it is extracted that the results of interpolating current with octet quantum numbers are in good agreement with the experimentally measured masses. The masses obtained with this interpolating current are m = 1513.64 +/- 8.76 MeV for 1P state with JP = 3 -, m' = 1687.91 +/- 0.31 MeV for 2P state with JP = 3 - and m = 1882.37 +/- 11.95 MeV for 2S state with JP = 3 + and they are consistent with the experimental masses of A(1520), A(1690), and A(1890), respectively, which confirm their spin-parity quantum numbers. Besides, we calculate the corresponding current coupling constants, which are utilized as inputs in the calculations of different form factors defining the widths of the states under study.
