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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: 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.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: 18Citation - 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 - 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 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(+).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: 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.
