Yazar "Kucukarslan, Ayse" seçeneğine göre listele

Listeleniyor 1 - 9 / 9
  • [ X ]
    Öğe
    Different Contributions of the ? ? K0 (K)over-bar0 ? Decay
    (Amer Inst Physics, 2011) Kucukarslan, Ayse; Unal, Yasemin
    The scalar mesons and vector mesons contribution to the radiative decay phi -> K-0(K) over bar (0) gamma are studied within the framework of the phenomenological approach. The branching ratio of this decay is calculated to be 10(-8) - 10(-12). Furthermore, obtained values are compared with the experimental and theoretical results existing in the literature.
  • [ X ]
    Öğe
    Different Contributions of the Decay ? ? ?0?0?
    (Iop Publishing Ltd, 2012) Aciksoz, Esra; Kucukarslan, Ayse
    The radiative decay rho -> pi(0)pi(0)gamma is re-examined within the framework of a phenomenological approach in which the f(2) meson and sigma are combined with the processes involving the vector meson intermediate states and the pion-loops. In order to obtain the scalar meson contribution we consider pion-loop model and no structure model, and then compare the results obtained in two models. Furthermore, using the experimental branching ratio for the radiative decay rho -> pi(0)pi(0)gamma, we estimate the coupling constant g(rho sigma gamma) for a set of values of sigma meson parameters M-sigma and Gamma(sigma).
  • [ X ]
    Öğe
    Fluorine-doped tin oxide films via ultrasonic spray pyrolysis: Investigation of physical properties post-annealing and their potential for TCO applications
    (Elsevier, 2024) Gunes, Ibrahim; Sarica, Emrah; Bilgin, Vildan; Kucukarslan, Ayse; Ozder, Serhat
    In this study, undoped tin oxide (SnO2) and fluorine (F)-doped SnO2 (FTO) films at various doping levels were deposited on glass substrates using the ultrasonic spray pyrolysis technique, followed by an annealing process applied to the films after deposition. In line with this, the study reveals the significant impact of the fluorine doping level optimization on certain physical properties such as the structural, optical, and electrical characteristics of the obtained films, and presents the consequences of the variation in these physical properties for adaptability in various optoelectronic applications. No diffraction peaks were observed in the X-ray diffraction patterns of the deposited films. After the annealing process, however, films with a polycrystalline form and a rutile tetragonal crystal structure were obtained. It was observed that the crystallization levels were better in films doped with 5 % and 10 % F. The optical band gap values of the films were determined to vary between 3.35 eV and 3.68 eV. Furthermore, it was found that with the increase in F doping level, the resistivity (ranging from 2.1 Omega cm to 43.5 Omega cm) and sheet resistance (ranging from 1.62x10(5) Omega/sq to 35.9x10(5) Omega/sq) values of the films decreased, while the figure of merit values (ranging from 0.12x10(-8) Omega(-1) to 67.1x10(-8) Omega(-1)) increased. Among all FTO films, it was revealed that films doped with 10 % F exhibited the highest optical transmittance, the lowest electrical resistivity, and the highest figure of merit values.
  • [ X ]
    Öğe
    ?-? mixing in chiral perturbation theory
    (World Scientific Publ Co Pte Ltd, 2006) Kucukarslan, Ayse; Meissner, Ulf-G.
    We investigate w-phi meson mixing to leading order in chiral perturbation theory utilizing the antisymmetric tensor field formulation. We update the quark mass ratio R from P-to mixing, R = 42 +/- 4.
  • [ X ]
    Öğe
    Radiative ???? Vertex in QCD Sum Rules and Phenomenological Approach
    (Amer Inst Physics, 2011) Kucukarslan, Ayse; Ozdem, Ulas; Unal, Yasemin
    We estimate the coupling constant g(phi sigma gamma)by using the three- point correlation function and we also investigate this coupling constant by studying the effective lagrangians. Here we consider the effect the phi-omega mixing effect to the calculation. Besides, a comparison of our predictions with the theoretical results existing in literature is presented.
  • [ X ]
    Öğe
    Scalar Mesons in the Decay ? ? K0(K)over-bar0?
    (Iop Publishing Ltd, 2012) Unal, Yasemin; Kucukarslan, Ayse
    We estimate the branching ratio of the phi -> K-0(K) over bar (0)gamma. decay within the framework of a phenomenological approach in which the contributions of the f(0)(980), a(0)(980) scalar resonances, chiral loops and K*(892) vector meson are considered. To evaluate the contribution of the scalar resonances, we consider the kaon-loop model and the no-structure model.
  • [ X ]
    Öğe
    Tailoring the physical properties of ultrasonically spray pyrolyzed SnS thin films with silver doping
    (Springer, 2025) Gunes, Ibrahim; Sarica, Emrah; Bilgin, Vildan; Kucukarslan, Ayse
    In this study, the effects of silver (Ag) doping on the structural, morphological, optical, and electrical properties of tin monosulfide (SnS) thin films were investigated. The films, undoped and doped with 3%, 6%, and 9% Ag, were deposited using the ultrasonic spray pyrolysis (USP) technique at a substrate temperature of 350 degrees C. X-ray diffraction (XRD) analysis confirmed a pi-SnS (cubic) structure with (400) preferred orientation for undoped and <= 6% Ag-doped films, while 9% doping induced amorphization due to severe lattice distortions. Morphological analyses revealed smooth, void-free surfaces, with average roughness increasing from 5.8 nm (undoped) to 19.6 nm (9% doping). Optical measurements showed that the band gap widened from 1.84 eV (undoped) to 2.47 eV (9% Ag-doped), and Urbach energy increased from 190 meV to 600 meV. Hall effect measurements confirmed p-type conductivity for all films. Resistivity ranged from 4.34 x 10(5) Omega cm to 9.48 x 10(5) Omega cm, carrier concentration varied between 2.7 x 10(12) cm(-3) and 5.6 x 10(12) cm(-3), while mobility decreased from 3.3 x 10(1) cm(2)/Vs to 2.0 x 10(1) cm(2)/Vs with increasing Ag doping. These findings demonstrate that Ag doping significantly influences the structural and optoelectronic behavior of SnS thin films, making them promising candidates for thin-film solar cells and optoelectronic applications.
  • [ X ]
    Öğe
    The behavior of the strange quark matter in the FRW universes
    (World Scientific Publ Co Pte Ltd, 2007) Yilmaz, Ihsan; Kucukarslan, Ayse; Ozder, Serhat
    In this paper, we study strange quark matter for Friedman - Robertson - Walker (FRW) universes in the context of general relativity. For this purpose we consider quark - gluon plasma as a perfect fluid in the FRW universes. After solving Einstein's field equations, we have analyzed this matter for the different types of universe. Also, we discuss the features of collapsing strange quark matter.
  • [ X ]
    Öğe
    The Effect of Fe and Co doping on the Physical Properties of CdO Films Deposited by Ultrasonic Spray Pyrolysis
    (Springer, 2025) Demirselcuk, Barbaros; Gunes, Ibrahim; Sarica, Emrah; Kus, Esra; Kucukarslan, Ayse; Bilgin, Vildan
    In this study, Cadmium Oxide (CdO) semiconductor films with different iron (Fe) and cobalt (Co) concentrations have been produced at 350 degrees C substrate temperature on the glass substrates by the ultrasonic spray pyrolysis method. In the first part of this study, the Fe element was doped in different ratios (2, 4, 6%) to CdO films, and the films were characterized. At the end of this stage, the optimum Fe doping ratio was determined for CdO films. In the second step, CdO films were dually doped with Fe + Co. The electrical resistivities of CdO:Fe films were determined using a four-probe technique to measure their conductivities, carrier concentrations, mobilities, and electrical conductivity types through Hall measurements. The produced films showed n-type electrical conductivity. It was determined that with increasing doping ratios, the electrical resistivity generally increased, and the films exhibited n-type conductivity. The XRD patterns revealed that the crystal structures of the films were polycrystalline and cubic in structure. The lections of (111), (200), (220), (311), and (222) planes were observed in the XRD patterns. Upon examination of the SEM images, it was observed that the films had nearly homogeneous surfaces and good adhesion to the substrate. By utilizing the fundamental absorption spectra of the films, it was determined that they exhibited direct bandgap transitions, and the bandgap energy values ranged from 2.34 to 2.65 eV. In the structural analysis, all films were found to have a polycrystalline structure and cubic CdO crystal system. When the SEM images of CdO:(Fe + Co) films were examined, it was observed that the films had almost homogeneous surfaces. Based on all these analyses, it was concluded that the doping elements Fe and Co significantly influenced the physical properties of CdO thin films.