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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.Article Analysis of Theb(s)→t(jp=2-) Transition in Light Cone Qcd Sum Rules(Amer Physical Soc, 2025) Aliev, T. M.; Sarac, Y.The semileptonic B & eth;s & THORN; -* T & eth;JP 1/4 2-& THORN;l & thorn;l- decays induced by flavor changing neural currents are investigated within the light cone quantum chromodynamics (QCD) sum rule method in the leading order of O & eth;as & THORN;. We apply the B meson distribution amplitudes up to twist-4 and calculate the relevant form form factors then adopted in the calculations of the corresponding widths. The present results can be used in future experiments for studying the properties of JP 1/4 2- tensor mesons.Article Citation - WoS: 19Citation - Scopus: 19Possible Molecular Pentaquark States With Different Spin and Quark Configurations(Amer Physical Soc, 2018) Azizi, K.; Sarac, Y.; Sundu, H.We investigate three possible pentaquark candidates, one of which contains a single charm quark and the other two contain triple charm quarks in their substructure. To this end we apply the QCD sum rule method and take into account both the positive and negative parity states corresponding to each possible pentaquark channel having spin 3/2 or 1/2. Insisting on the importance of identification of the members of the pentaquark family we obtain their spectroscopic parameters such as masses and residues. These parameters are the main inputs in the searches for their electromagnetic, strong, and weak interactions.Article Citation - WoS: 83Citation - Scopus: 80Analysis of pc< and pc< as Pentaquark States in the Molecular Picture With Qcd Sum Rules(Amer Physical Soc, 2017) Azizi, K.; Sarac, Y.; Sundu, H.To better understand the nature and internal structure of the exotic states discovered by many collaborations, more information on their electromagnetic properties and their strong and weak interactions with other hadrons is needed. The residue or current coupling constant of these states together with their mass are the main inputs in determinations of such properties. We perform QCD sum rules analyses on the hidden-charm pentaquark states with spin parities J(P) = 3/2 (+/-) and J(P) = 5/2 (+/-) to calculate their residue and mass. In the calculations, we adopt a molecular picture for J(P) = 3/2(+/-) states and a mixed current in a molecular form for J(P) = 5/2(+/-). Our analyses show that the P-c(+) (4380) and P-c(+) (4450), observed by the LHCb Collaboration, can be considered as hidden-charm pentaquark states with J(P) = 3/2(-) and JP = 5/2(+), respectively.Article Citation - WoS: 10Citation - Scopus: 11Investigation of the Strange Pentaquark Candidate Pλψsð4338þ0 Recently Observed by Lhcb(Amer Physical Soc, 2023) Azizi, K.; Sarac, Y.; Sundu, H.The recently observed strange pentaquark candidate, P Lambda yso4338 thorn 0, is investigated to provide information about its nature and substructure. To this end, its mass and width through the decay channels P Lambda yso4338 thorn 0 -> J=y Lambda and P Lambda yso4338 thorn 0 -> ric Lambda are calculated by applying two- and three-point QCD sum rules, respectively. The state is considered as a Xi c D over bar meson-baryon molecular structure with spin-parity quantum numbers JP 1/4 1 -. The obtained mass, mP Lambda 2 yso4338 thorn 0 1/4 4338 130 MeV, and width, Gamma P Lambda yso4338 thorn 0 1/4 10.40 1.93 MeV, are consistent with the experimental data within the presented uncertainties. This allows us to assign a Xi c D over bar molecular structure of JP 1/4 1 - for the P Lambda yso4338 thorn 0 state.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: 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: 4Citation - Scopus: 4gΣQΣQπ coupling constant via light cone QCD sum rules(Amer Physical Soc, 2010) Azizi, K.; Bayar, M.; Ozpineci, A.; Sarac, Y.Using the most general form of the interpolating currents, the coupling constants g(Sigma b Sigma b pi) and g(Sigma c Sigma c pi) are calculated within the light cone QCD sum rules approach. It is found that g(Sigma c Sigma c pi) = -8.0 +/- 1.7 and g(Sigma b Sigma b pi) = -11.0 +/- 2.1.Article Citation - WoS: 17Citation - Scopus: 18Λb< State Newly Observed by Lhcb(Amer Physical Soc, 2020) Azizi, K.; Sarac, Y.; Sundu, H.We study the bottom Lambda(b)(6146)(0) baryon, newly discovered by the LHCb Collaboration. By adopting an interpolating current of (L-rho, L-lambda) = (0, 2) type and D-wave nature with spin-parity quantum numbers J(P) = 3/2(+) for this heavy bottom baryon, we calculate its mass and residue. Using these spectroscopic parameters, we also investigate its dominant decays Lambda(b)(6146)(0) -> Sigma(b)pi and Lambda(b)(6146)(0) -> Sigma(*)(b)pi and estimate the width of Lambda(b)(6146)(0) obtained via these channels. The obtained mass, m(Lambda b) = (6144 +/- 68) MeV is in accord nicely with the experimental data. The width obtained via the dominant channels is also consistent with the experimental data of LHCb collaboration. We calculate the spectroscopic parameters and the same decay channels for the c-partner of Lambda(b)(6146)(0) state, namely Lambda(c)(2860)(+), as well. We compare the obtained results with the existing theoretical predictions as well as experimental data. The results indicate that the state Lambda(b)(6146)(0) and its charmed-partner Lambda(c)(2860)(+) can be considered as 1D-wave baryons with J(P) = 3/2(+).
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