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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.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: 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: 8Interpretation of the Λc< Baryon Newly Seen by Belle Collaboration and Its Possible Bottom Partner(Springer, 2022) Azizi, K.; Sarac, Y.; Sundu, H.The developments in the experimental facilities and analyses techniques have recently lead to the observation of many hadronic states ranging from excitations of conventional hadrons to various exotic states. The baryons with single heavy quark are among these states providing an attractive field of research to get a better understanding of the nonperturbative nature of the strong interaction. Recently, the Belle Collaboration announced observation of the state Lambda(c)(2910)(+) with a mass 2913.8 +/- 5.6 +/- 3.8 MeV/c(2) and width 51.8 +/- 20.0 +/- 18.8 MeV. In the present study, by the mass analyses of different excitations at A c channel and their comparison with existing experimental information, we find that the spin-parity of this newly found excited state is J(P) = 1/2(-) and it is a 2 P state denoting by Lambda(c)(1/2(-), 2 P). We predict its current coupling as well, which can be served as one of the main input parameters to investigate different decays and interactions of this particle. We also determine the mass and current coupling of Lambda(b)(1/2(-), 2 P) as possible bottom counterpart of the new Lambda(c)(2910)(+) state, which may be in agenda of different experiments in near future.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: 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: 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.
