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Citation - WoS: 31
Citation - Scopus: 30
Structure of the Ξ_b< 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(-).
Citation - WoS: 12
Citation - Scopus: 12
Investigation of a Candidate Spin-1/2 Hidden-Charm Triple Strange Pentaquark State p_csss<
(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.
Citation - WoS: 27
Citation - Scopus: 27
Lepton 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.
Citation - WoS: 18
Citation - Scopus: 17
Strong Λ_bNB and Λ_cND 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.
Citation - WoS: 12
Citation - Scopus: 12
New Λ_b< 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.
Citation - WoS: 1
Citation - Scopus: 1
AdS3 Black Holes with Primary Proca Hair from a Regularized Gauss-Bonnet Coupling
(Amer Physical Soc, 2025) Alkac, Gokhan; Mesta, Murat; Unal, Gonul
We construct a consistent three-dimensional Einstein-Gauss-Bonnet theory as a vector-tensor theory within the generalized Proca class by employing a regularization procedure based on the Weyl geometry, which was introduced recently by Charmousis, Fernandes, and Hassaine [Phys. Rev. D 111, 124008 (2025).]. We then obtain an asymptotically Anti-de Sitter (AdS3), static, and circularly symmetric black hole solution with primary Proca hair. Afterward, we investigate the effect of the scalar-tensor GaussBonnet coupling constructed previously by different regularization schemes. We further generalize these solutions by incorporating an electric charge. As special cases, we find a regular black hole solution in addition to charged and uncharged stealth Banados-Teitelboim-Zanelli black hole solutions.
Citation - Scopus: 1
Investigations 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.
Citation - WoS: 7
Citation - Scopus: 7
Tree 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.
Citation - WoS: 17
Citation - Scopus: 18
Λ_b< 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(+).
Citation - WoS: 32
Citation - Scopus: 34
Semileptonic Λ_b,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.

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