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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: 13Citation - Scopus: 15Induced Scattering Limits on Fast Radio Bursts From Stellar Coronae(Iop Publishing Ltd, 2016) Lyubarsky, Yuri; Ostrovska, SofiyaThe origin of fast radio bursts remains a puzzle. Suggestions have been made that they are produced within the Earth's atmosphere, in stellar coronae, in other galaxies, or at cosmological distances. If they are extraterrestrial, the implied brightness temperature is very high, and therefore the induced scattering places constraints on possible models. In this paper, constraints are obtained on flares from coronae of nearby stars. It is shown that the radio pulses with the observed power could not be generated if the plasma density within and in the nearest vicinity of the source is as high as is necessary to provide the observed dispersion measure. However, one cannot exclude the possibility that the pulses are generated within a bubble with a very low density and pass through the dense plasma only in the outer corona.Article Citation - WoS: 12Citation - Scopus: 12Fcnc Transitions of Λb,c< To Nucleon in Sm(Iop Publishing Ltd, 2010) Azizi, K.; Bayar, M.; Sarac, Y.; Sundu, H.We provide a comprehensive study of semileptonic flavor-changing neutral current transitions for Lambda(b) -> nl(+) l(-) and Lambda(c) -> pl(+) l(-) in the context of light cone QCD sum rules. Using the most general form of the interpolating current for Lambda(b),(c), as well as nucleon distribution amplitudes, we calculate all 12 form factors entering the calculations in full theory. We obtain the order of heavy quark effective theory violation and argue that the Lambda(b) -> nl(+) l(-) case can be studied at LHC, but the other one has a very small branching ratio.Article Citation - WoS: 3Citation - Scopus: 3Nucleon Resonances With Spin 3/2 and Isospin 1/2(Iop Publishing Ltd, 2020) Azizi, K.; Sarac, Y.; Sundu, H.Investigation of the nucleon's excited states has always become an important research topic because of the rich information they provide. Since their first observation, dating back about 70 years, the investigation of their various parameters contributed both to the development of the quark model and a better understanding of the QCD as the theory of strong interaction. Their investigation still has importance. The research conducted on the nucleon excited states is helpful to probe the missing resonances predicted by the quark model but not observed yet. With this motivation, we study the low lying nucleon resonance with I(J(P)) = 1/2(3/2(-)) and its corresponding orbital and radial excitations with I(J(P)) = 1/2(3/2(+)) and I(J(P)) = 1/2(3/2(-)), respectively. Using the QCD sum rule method, we calculate the masses and pole residues of these states. The obtained mass results are consistent with the mass ranges presented in PDG for the resonances N(1520)(3/2(-)), N(1700)(3/2(-)), and N(1720)(3/2(+)). The results of masses and residues of these states may be used as input parameters to calculate various quantities related to their electromagnetic, weak and strong interactions with other particles with the aim of getting more information on their natures and structures.
