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Full-Text Articles in Physical Sciences and Mathematics

Mapping Heavy Elements In The Supernova Remnant G290.1-0.8, Murat Hüdaverdi̇ Jan 2018

Mapping Heavy Elements In The Supernova Remnant G290.1-0.8, Murat Hüdaverdi̇

Turkish Journal of Physics

We present the imaging and spectroscopic study results of G290.1-0.8 Supernova Remnant (SNR) using the Suzaku X-ray archival data. The SNR belongs to the mixed-morphology class with its centrally peaked asymmetric X-ray core and distorted radio shell-like plasma. The X-ray spectra is well defined with isothermal plasma of kTe ∼ 0:5 keV. The radial profile shows enhanced elemental abundances. The EW maps reveal inhomogeneous asymmetric spatial distribution of elemental abundances. The northeast of the SNR is bright in Ne, Mg, and Si. The EW maps are enhanced in the direction of the X-ray elongation, suggesting that the distorted X-ray structure …


Electrochemical Capacitance-Voltage Profiling Of Nonuniformly Doped Gaas Heterostructures With Sqws And Mqws For Led Applications, George Yakovlev, Vasily Zubkov, Anna Solomnikova, Oleg Derevianko Jan 2018

Electrochemical Capacitance-Voltage Profiling Of Nonuniformly Doped Gaas Heterostructures With Sqws And Mqws For Led Applications, George Yakovlev, Vasily Zubkov, Anna Solomnikova, Oleg Derevianko

Turkish Journal of Physics

Light-emitting heterostructures with single and multiple GaAs/InGaAs quantum wells have been investigated by means of electrochemical capacitance-voltage (ECV) profiling. Capacitance-voltage characteristics were measured; concentration profiles of free charge carriers over the heterostructure depth as well as the intensity of quantum well filling by charge carriers were obtained. In heterostructures with a single quantum well (QW), we considered limitations of capacitance techniques for undoped QW profiling, which are situated near the metallurgic border of the p-n junction. We made a detailed consideration of phenomena related to Debye smearing and we developed and analyzed the dependence of the space charge region width …


Symmetry Reduction Of The First Heavenly Equation And $2+1$-Dimensional Bi-Hamiltonian System, Devri̇m Yazici Jan 2018

Symmetry Reduction Of The First Heavenly Equation And $2+1$-Dimensional Bi-Hamiltonian System, Devri̇m Yazici

Turkish Journal of Physics

The first heavenly equation of Plebanski in the two-component form is known to be a $3+1$-dimensional tri-Hamiltonian system. We show that a particular choice of symmetry reduction applied to the first heavenly equation yields a $2+1$-dimensional bi-Hamiltonian system. For this tri-dimensional system, we present Lagrangian, Hamiltonian, and recursion operators; point symmetries; and integrals of motions.


Analysis Of Quantum-Dot-Embedded Multicavity Arrays For On-Chip Wdm Applications, Havva Erdi̇nç, Serdar Kocaman Jan 2018

Analysis Of Quantum-Dot-Embedded Multicavity Arrays For On-Chip Wdm Applications, Havva Erdi̇nç, Serdar Kocaman

Turkish Journal of Physics

Transmission and group delay characteristics of a single-quantum-dot-(QD)-embedded double-cavity array and a triple-cavity array are compared theoretically in the weak coupling regime. When the extrinsic cavity decay rate is comparably higher than the intrinsic cavity decay rate at equal coupling strengths and normalized detuning values, transmission values of both systems converge with each other but the phase delay generated at triple-cavity systems is higher than that of the single-QD-embedded double-cavity array system. The results confirmed by the transmission calculations for both cases provide a comparative tool for designing on chip wavelength division multiplexing systems.


The Investigation Of The Lattice Strains And Crystallite Sizes Of Y358 And Y123 High-Temperature Superconductors, İbrahi̇m Düzgün Jan 2018

The Investigation Of The Lattice Strains And Crystallite Sizes Of Y358 And Y123 High-Temperature Superconductors, İbrahi̇m Düzgün

Turkish Journal of Physics

In this study, the Y358 phase, the newest high-temperature superconductor member of the yttrium barium copper oxide family, was produced using the solid-state reaction technique. The Y358 superconductor exhibited the Meissner effect at low temperature (77 K). The X-ray diffraction spectra indicated that the crystal structure was almost identical to that of Y123, but with some impurity peaks. An X-ray peak broadening analysis was applied to determine the lattice strain, and the medial crystallite size was calculated perpendicular to the surface of the superconductor specimens. As a result of the analyses, it was determined that the crystallite size of the …


Noether Symmetry Analysis Of Anisotropic Universe In F(T;B) Gravity, Yusuf Küçükakça Jan 2018

Noether Symmetry Analysis Of Anisotropic Universe In F(T;B) Gravity, Yusuf Küçükakça

Turkish Journal of Physics

The purpose of the present work was to investigate the Noether symmetries of the locally rotationally symmetric Bianchi type I space time in f(T;B) gravity theory, which depends on the torsion scalar T and the boundary term B. In this theory, we consider some particular models and investigate their Noether symmetry generators. Besides, we get exact cosmological solutions of the considered models including the matter dominant universe using the Noether symmetry technique. The obtained results coincide with the accelerated expansion behavior of the universe.


Soliton Solutions Of Perturbed Nonlinear Schrodinger Equation With Kerr Lawnonlinearity Via The Modified Simple Equation Method And The Subordinarydifferential Equation Method, Singh Subhaschandra Salam Jan 2018

Soliton Solutions Of Perturbed Nonlinear Schrodinger Equation With Kerr Lawnonlinearity Via The Modified Simple Equation Method And The Subordinarydifferential Equation Method, Singh Subhaschandra Salam

Turkish Journal of Physics

The objective of this paper was to obtain soliton solutions for a perturbed nonlinear Schrodinger equation with Kerr law nonlinearity using the modified simple equation method and subordinary differential equation method. These methods appear to be efficient and they can be applied in seeking exact solutions of many other nonlinear evolution equations encountered in science and engineering studies.


Size- And Composition-Dependent Structure Of Ternary Cd-Te-Se Nanoparticles, Mustafa Kurban Jan 2018

Size- And Composition-Dependent Structure Of Ternary Cd-Te-Se Nanoparticles, Mustafa Kurban

Turkish Journal of Physics

In this study, the geometrical, thermal, and energetic properties of zinc-blende CdTe1-xSex (x = 0.25, 0.50, and 0.75) nanoparticles were investigated using the bond order potential based on the modern classical molecular dynamics (MD) method. All MD simulations were performed using LAMMPS. Some physical properties were investigated, such as compositional variations of Cd, Te, and Se atoms; order parameter; radial distribution function; coordination number; potential energy; and heat capacity (Cv). The simulation results were compared with the available experimental results. The obtained results revealed that an increase in the composition of Se atoms can provide contributions to stability, which is …


Forward-Backward Asymmetry Of Drell-Yan Lepton Pairs At 14 Tev Center-Of-Mass Energy, Kamuran Di̇lsi̇z, Hasan Oğul Jan 2018

Forward-Backward Asymmetry Of Drell-Yan Lepton Pairs At 14 Tev Center-Of-Mass Energy, Kamuran Di̇lsi̇z, Hasan Oğul

Turkish Journal of Physics

In this paper, fiducial cross-sections of lepton pairs with opposite charge via Z → l+ l- (l± = μ±, e±) are calculated at a center-of-mass energy of 14 TeV by applying different transverse momentum selections to evaluate their impact on the production cross-section as well as the differential cross-section of Z bosons in terms of lepton pseudorapidity. The predictions are computed by next-to-next-to-leading order quantum chromodynamics including next-to-leading order electroweak corrections. Forward-backward asymmetry prediction for the Drell?Yan production in proton-proton collision is further calculated at 14 TeV using HERAPDF2.0, MMHT2014, NNPDF3.1, and CT14 parton distribution function models. Then 14 TeV …


Investigation Of The Optical Properties Of The Liquid Crystal-Based Devices Via Mueller Matrix Formalism, Ömer Polat Jan 2018

Investigation Of The Optical Properties Of The Liquid Crystal-Based Devices Via Mueller Matrix Formalism, Ömer Polat

Turkish Journal of Physics

A model approach for the Mueller matrix (MM) of the twisted nematic liquid crystal spatial light modulator (TNLC-SLM) was proposed. In the first part of the study, the MM of the TNLC cell in the absence of applied voltage was investigated both theoretically and experimentally. In the second part, the model approach was improved by considering the reorientation of both tilt and azimuth angles of the liquid crystal (LC) molecules in the presence of applied voltage. Comparison of the theoretical MM elements with the experimental ones from the literature showed that, instead of decaying exponentially, the azimuth angle rotates with …


Design Of A Multifunctional Sample Probe For Transport Measurements, Mustafa Öztürk, Numan Akdoğan Jan 2018

Design Of A Multifunctional Sample Probe For Transport Measurements, Mustafa Öztürk, Numan Akdoğan

Turkish Journal of Physics

Herein, we describe a multifunctional sample probe equipped with a two-axis goniometer for transport measurements. The two-axis goniometer enables both computer-controlled 360$^{\circ}$ out-of-plane and manual 360$^{\circ}$ in-plane rotations. The multifunctional sample probe was successfully implemented to a host dewar and an electromagnet system. The developed probe is capable of performing transport measurements while fully controlling the parameters such as the magnetic and electrical fields, the angle, the temperature, and the current/voltage parameters in a wide range. The design of the multifunctional sample probe allows easy installation into different dewar and magnet systems and connection of a wide range of external …


Permanent Magnet Motion In A Copper Tube, Jaroslav Franek, Martin Soka Jan 2018

Permanent Magnet Motion In A Copper Tube, Jaroslav Franek, Martin Soka

Turkish Journal of Physics

This paper deals with the investigation of braking forces induced by eddy currents, which have effects on the permanent magnet moving at a constant speed in the direction of the conductive tube axis. The analysis is based on calculation of an action of a force between the current density, representing the magnet, and the eddy currents. The chosen solution is based on classical electrodynamics and can serve as a guide for the calculation of other cases, where braking forces are created between the moving cell, which is a source of the magnetic field, and a close conductive subject. The obtained …


Control Of Laser-Induced Nonadiabatic Molecular Alignment In Dissipative Media, Gamze Kaya Jan 2018

Control Of Laser-Induced Nonadiabatic Molecular Alignment In Dissipative Media, Gamze Kaya

Turkish Journal of Physics

Laser-induced nonadiabatic alignment in nitrogen and mixtures of nitrogen with Ar gas was investigated using the ultrafast optical Kerr effect in the collinear pump-probe setup. We find that dissipative media produce desired alignment characteristics in distinct manners to decoherence and to population relaxation. The results show that the intense laser alignment can be used as a control tool of molecular dynamics in dissipative environments.


Quantum Many-Body Interactions In The Presence Of Disordered Potentials, Riza Oğul Jan 2018

Quantum Many-Body Interactions In The Presence Of Disordered Potentials, Riza Oğul

Turkish Journal of Physics

The time evolution of the quantum nonequilibrium states of many-body particles is described with a set of hierarchies of quantum kinetic equations with quantum wave functions. A collision term is obtained in terms of two-body interactions in the mean-field with a disordered potential, which is proposed for the first time. The implications and the limits of applicability of the resulting kinetic equations are discussed.


Thermodynamics Of Cosmological Models With Generalized $G$ And $\Lambda $, M Saratchandra Singh, Sanasam Surendra Singh Jan 2018

Thermodynamics Of Cosmological Models With Generalized $G$ And $\Lambda $, M Saratchandra Singh, Sanasam Surendra Singh

Turkish Journal of Physics

Here we investigate spatially flat Friedmann-Robertson-Walker space-time models of the universe to study the thermodynamic behaviors in light of variables $G$ and $\Lambda $. A particular method to find the solutions of Einstein's field equations and mathematical expressions for temperature and entropy of the perfect fluid cosmological models is introduced by using both the equation of state and the assumption $G=G_{0} \,a^{n}$. It is observed that the phantom field of ($\omega


Silicon Nitride As Antireflection Coating To Enhance The Conversion Efficiency Of Silicon Solar Cells, Rajinder Sharma Jan 2018

Silicon Nitride As Antireflection Coating To Enhance The Conversion Efficiency Of Silicon Solar Cells, Rajinder Sharma

Turkish Journal of Physics

The aim of this work is to investigate the effect of single and double layer antireflection coating (ARC) on the performance of silicon solar cells. In this regard, various previous works on single and double layer ARCs have been consulted. Silicon nitride (Si3N4) has been used as ARC material because of its varying refractive index (1.8-3.0). Numerical calculations have been performed to obtain the reflectance for single and double layer Si3N4 using the transfer matrix method. Double layer antireflection coating (DLARC) of Si3N4 is found to have significant advantages over single layer antireflection coating (SLARC). Calculated reflectances have been further …


An Experimental Study On The Angular Dependence Of Coherent To Compton Scattering Differential Cross-Section Ratios Of Calcium, Tuba Akkuş Jan 2018

An Experimental Study On The Angular Dependence Of Coherent To Compton Scattering Differential Cross-Section Ratios Of Calcium, Tuba Akkuş

Turkish Journal of Physics

The coherent to Compton scattering cross-section ratio of calcium was measured experimentally for several polar scattering angles (90°, 100°, 110°, 120°, and 130°) and azimuthal scattering angles (30°, 20°, 10°, 0°, -10°, and -20°). A high purity germanium semiconductor detector with a resolution of 199.6 eV at 5.9 keV was used. The theoretical values of the coherent to Compton scattering differential cross-section of calcium were calculated on the basis of nonrelativistic form factors, relativistic form factors, and S-matrix theories. It was observed that the experimental results were most compatible with the nonrelativistic form factor theory.


Size Investigation Of Silicon Nanoclusters Deposited On Hopg Using Noncontact Atomic Force Microscopy, Mümi̇n Mehmet Koç Jan 2018

Size Investigation Of Silicon Nanoclusters Deposited On Hopg Using Noncontact Atomic Force Microscopy, Mümi̇n Mehmet Koç

Turkish Journal of Physics

The sizes of silicon nanoparticles produced using two different novel methods are investigated in this report. The method of production used to generate silicon oxide nanoparticles was achieved via gas aggregation codeposition with water on a cold target, and also via a liquid jet method. The nanoparticles were drop-cast on a highly oriented pyrolytic graphite (HOPG) substrate and assessed using ultrahigh vacuum atomic force microscopy (AFM). Noncontact constant force mode was used in the AFM investigations. The silicon nanoparticles produced using the gas aggregation and water codeposition method were found to be smaller than 2 nm. A degree of deviation …


On Oxygen-Rich Sr Variables In The Solar Neighborhood, Tuncay Özdemi̇r Jan 2018

On Oxygen-Rich Sr Variables In The Solar Neighborhood, Tuncay Özdemi̇r

Turkish Journal of Physics

Brightness distribution of variable stars was investigated based on good Hipparcos parallaxes of semiregular variables (SRVs) in the solar neighborhood, and it is shown that the order of the variability types Lb, SR, SRb, SRa, and Mira is, statistically, an order of increasing brightness along the red giant branch and asymptotic giant branch. In addition, it is also shown that the majority of Miras are above and majority of SRVs are below the tip of the red giant branch. The periods of SRVs that fall in Wood's sequence C (fundamental mode) of large Magellanic clouds were identified. Statistically, the order …


One-Dimensional Fluid And Hybrid Numerical Analysis Of The Plasma Properties Inthe Discharge Channel Of A Hall Thruster, Çinar Yüncüler, İsmai̇l Rafatov, Demet Uluşen Aksoy Jan 2018

One-Dimensional Fluid And Hybrid Numerical Analysis Of The Plasma Properties Inthe Discharge Channel Of A Hall Thruster, Çinar Yüncüler, İsmai̇l Rafatov, Demet Uluşen Aksoy

Turkish Journal of Physics

One-dimensional fluid and hybrid fluid-kinetic numerical codes are developed and applied to the analysis of axial distributions of plasma properties in the discharge channel of a Hall-effect thruster. Within the hybrid model ions are described by the kinetic Vlasov equation, while electrons and neutral atoms are treated as fluids. The results obtained from fluid and hybrid models are compared. Different operating regimes such as damped, periodic, and aperiodic irregular oscillations about the stationary state are observed and discussed. Thrust and efficiency of the thruster for different input parameters are estimated.


Triple Higgs Boson Production In A Γγ-Collider At The Future Linear Collider, Nasuf Sönmez Jan 2018

Triple Higgs Boson Production In A Γγ-Collider At The Future Linear Collider, Nasuf Sönmez

Turkish Journal of Physics

In this study, triple Higgs boson production channels in a γγ-collider are investigated in the context of the two-Higgs-doublet model (2HDM). This model has three neutral Higgs bosons (h0/H0/A0 ) and two charged Higgs bosons (H±). Between all the possible combinations of the triple Higgs bosons in the final state, only the following two scattering processes are probable at tree-level: γγ → H+H-h0 and γγ → H+H-H0. These two processes are important to determine the triple Higgs self-couplings gH+H-h0 and gH+H-H0 in the 2HDM. The calculation is carried out for two scenarios, which are inspired by recent experimental and theoretical …


Annealing Effect Of Gold Thin Films On The Light Output Performances Of Organic Light Emitting Diodes, Seli̇n Piravadili Mucur, Emi̇ne Teki̇n Jan 2018

Annealing Effect Of Gold Thin Films On The Light Output Performances Of Organic Light Emitting Diodes, Seli̇n Piravadili Mucur, Emi̇ne Teki̇n

Turkish Journal of Physics

Gold thin films (GTFs) are transferred onto a nanostructured surface and their effects on the characteristics of organic light emitting diodes (OLED) are investigated. GTF deposition is realized by the physical vapor deposition technique under high vacuum. Globose gold nanostructures are successfully generated by annealing GTFs at different temperatures. Atomic force microscopy reveals morphological changes affected by film thicknesses and annealing temperatures. In the tailored device architecture, GTFs, [poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene are used as a hole injection layer, a hole transport layer, and an emissive layer, respectively. The performances of the fabricated OLEDs are enhanced in the presence …


Field Electron Emission Area Revisited: An Integrated Method For The Area Extraction Model, Ahmed Abdulrahman Al-Tabbakh Jan 2018

Field Electron Emission Area Revisited: An Integrated Method For The Area Extraction Model, Ahmed Abdulrahman Al-Tabbakh

Turkish Journal of Physics

For electron field emitters, the emitter's physical and geometrical parameters, namely the emitter work function and its geometrical factor, are extracted from the slope of the Fowler-Nordheim (FN) plot. The literature contains few investigations and reviews of extended parameter extraction models based on the slope and intercept of the FN plot. However, due to the complexity of these reviews, there is a great need for an integrated approach to the area extraction model whereby a simplified account of the derivation and implementation of the model is presented and made convenient, especially for scholars other than physicists and engineers. This is …


Surface Effect In Explaining The Elastic Scattering Of The $\Alpha +^{12}$C System At Low Energies, Yasemi̇n Küçük Jan 2018

Surface Effect In Explaining The Elastic Scattering Of The $\Alpha +^{12}$C System At Low Energies, Yasemi̇n Küçük

Turkish Journal of Physics

In this paper, the elastic scattering angular distributions data of the $\alpha +$12C reaction at an energy range of 13.0 to 172.5 MeV were analyzed within the framework of optical model formalism. A phenomenological deep real potential was used with a phenomenological Woods-Saxon type imaginary potential. Excellent agreement was obtained in the high-energy region. The phenomenological deep potential was unable to explain the experimental data in the low-energy region. The experimental data at both low and high energies could not be explained at the same time. In order to explain the data simultaneously at low energy and high energy, the …


Investigation Of The Influence Of Various Reflector Elements Material Types On The Core Nuclear Parameters Of The 2 Mw Triga Mark-Ii Research Reactor Using The Monte Carlo Code, Abdelaziz Darif, Abdelouahed Chetaine, Mohammed Mghar, Ouadie Kabach Jan 2018

Investigation Of The Influence Of Various Reflector Elements Material Types On The Core Nuclear Parameters Of The 2 Mw Triga Mark-Ii Research Reactor Using The Monte Carlo Code, Abdelaziz Darif, Abdelouahed Chetaine, Mohammed Mghar, Ouadie Kabach

Turkish Journal of Physics

The influence of variation in the kind of material of neutron reflector elements on the core neutronic parameters of the Moroccan Triga Mark-II research reactor was examined. The comparison was made between three kinds of reflector element materials: graphite, beryllium, and beryllium oxide. MCNP5 Monte Carlo computations of the effective neutron multiplication factor (${k}_{{eff}})$ of the reactor according to the number of reflector material elements inserted in the reactor core for these three reflector elements materials families were carried out. The results found could be used in order to increase the ${k}_{{eff}}$ parameter without changing the size of the reactor.


Quark Gluon Plasma And Upsilon Suppression, Rismita Ghosh, Aparajita Bhattacharya, Ballari Chakrabarti Jan 2018

Quark Gluon Plasma And Upsilon Suppression, Rismita Ghosh, Aparajita Bhattacharya, Ballari Chakrabarti

Turkish Journal of Physics

The time-dependent suppression probability P(t) of upsilon particles has been estimated due to the screening when embedded in the medium of quark gluon plasma where the screened potential is represented by an optical potential of type $V(r,\lambda) = - [\frac{V_{0}+iW_{0}}{1+exp((r-R)\lambda)}]$. A similar type of variation of suppression probability has been obtained by others. It has been observed that $t_{\frac{1}{2}}$ for melting of $\Upsilon$ is $\sim$ 1.5 fm/c. The variation of the screening radii of heavy mesons $(J/\psi, \Upsilon)$ for 1S and 2S states with respect to plasma radius have also been investigated with the same complex screening potential. We have …


Bessel And Bessel Vortex Beams Generated By Blunt-Tip Axicon, Ramazan Şahi̇n Jan 2018

Bessel And Bessel Vortex Beams Generated By Blunt-Tip Axicon, Ramazan Şahi̇n

Turkish Journal of Physics

A theoretical prediction of the propagation characteristics of Laguerre--Gaussian beams after passing through a blunt-tip axicon is presented. An ideal axicon generates theoretically perfect diffraction-free and smooth-on-axis intensity Bessel beams, while experiments and calculations show that a zeroth-order Bessel beam deviates from its perfect behavior. Strong intensity modulation occurs due to interference around the center of the beam. The origin of these oscillations should be explored to increase the quality of beam shaping. This research shows that these oscillations can be reduced by stopping the beam center for a small portion or by optimizing input beam parameters. On the other …


A Note On Noncompact And Nonmetricit Quadratic Curvature Gravity Theories, Suat Dengi̇z Jan 2018

A Note On Noncompact And Nonmetricit Quadratic Curvature Gravity Theories, Suat Dengi̇z

Turkish Journal of Physics

In this note, we evaluate the Weyl-invariant quadratic curvature tensors for the particular Weyl gauge field constructed in the $3+1$-dimensional noncompact Weyl-Einstein-Yang-Mills model. We subsequently extend the model to its higher curvature version. We also compute the Weyl-invariant extension of the topological Gauss-Bonnet term for this specific choice of vector field.


Predictions On Three-Particle Azimuthal Correlations In Proton-Proton Collisions, Şener Özönder Jan 2018

Predictions On Three-Particle Azimuthal Correlations In Proton-Proton Collisions, Şener Özönder

Turkish Journal of Physics

The ridge signal, which is long-ranged in rapidity, in di-hadron correlations in high-multiplicity p-p and p-A collisions opened up a whole new research area in high-energy QCD. Although the ridge had been observed in A-A collisions and interpreted as a result of the radial flow of quark-gluon plasma, it had not appeared until recently in the data of small collision systems such as p-p and p-A, nor had it been predicted theoretically or seen in event generators. There are two competing approaches that attempt to explain the systematics of the di-hadron ridge signal: hydrodynamics and gluon saturation physics (color glass …


Cycloid Experiment For Freshmen Physics Labs, Resat Akoglu, Seyedhabibollah Mazharimousavi, Mustafa Halilsoy Jan 2018

Cycloid Experiment For Freshmen Physics Labs, Resat Akoglu, Seyedhabibollah Mazharimousavi, Mustafa Halilsoy

Turkish Journal of Physics

We establish an instructive experiment to investigate the minimum time curve traveled by a small billiard ball rolling in a grooved track under gravity. Our intention is to popularize the concept of minimum time curves anew for pedagogical reasons and to propose it as a feasible physics experiment both for freshmen and sophomore classes. The experiment is simplified enough to provide motivation for the students. We observed that even the students who were not physics majors enjoyed such a cycloid experiment.