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2002

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Articles 451 - 480 of 530

Full-Text Articles in Physics

Experimental Investigation Of Temperature Effect On Refractive Index Of Dye Laser Liquids, Şeref Yaltkaya, Ramazan Aydin Jan 2002

Experimental Investigation Of Temperature Effect On Refractive Index Of Dye Laser Liquids, Şeref Yaltkaya, Ramazan Aydin

Turkish Journal of Physics

In this work, refractive index of selected dye laser solutions were measured by fiber optic sensor. The fiber optic probe was dipped into the liquids and according to Fresnel's Reflection Law, refractive index values were obtained at the wavelength of the laser utilized. The solutions consisted of Rhodamine 6G, Rhodamine B and Coumarin 481 dissolved in methanol, and ethylene glycol, respectively. Refractive index variations of the dye solutions and their solvents with temperature were measured and the refractive index temperature coefficient dn/dT were calculated at the wavelength of 780 nm.

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Temperature Dependence Of Galvanomagnetic Properties For Lightly Doped N-Type Si, Aytunç Ateş, Beki̇r Gürbulak, Seydi̇ Doğan, Muhammet Yildirim, Sebahatti̇n Tüzemen Jan 2002

Temperature Dependence Of Galvanomagnetic Properties For Lightly Doped N-Type Si, Aytunç Ateş, Beki̇r Gürbulak, Seydi̇ Doğan, Muhammet Yildirim, Sebahatti̇n Tüzemen

Turkish Journal of Physics

The temperature dependence of Hall and magnetoresistance effects in n-type Si having a resistivity of 1400 {\Omega } cm at room temperature is studied in the temperature range of 210-320 K. The variation of transverse magnetoresistance as a function of temperature is similar to the longitudinal magnetoresistance variation in < 001 > and < 1\bar {1}0 > n-Si the samples. It is observed that, in < 001 > sample, the transverse and longitudinal magnetoresistance variation is greater than that in the < 1\bar {1}0 > sample. In both samples, the temperature dependences of magnetoresistance is in accordance to double space anisotropy parameters. In both samples, the transverse and longitudinal magnetoresistance coefficents increase with increasing …

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Dependence Of Neutron-Proton Entity Transfer On Superfluid Parameters, Hüseyi̇n Ayteki̇n Jan 2002

Dependence Of Neutron-Proton Entity Transfer On Superfluid Parameters, Hüseyi̇n Ayteki̇n

Turkish Journal of Physics

In this study the nuclear matrix elements of neutron-proton (n-p) entity transfer of even-even nuclei are investigated in the Tamm-Dancoff Approximation (TDA). These matrix elements are used for n-p entity stripping from even-even nuclei and n-p entity absorbing of even-even nuclei. It is shown that the matrix element of 0^{+} \to 0^{+} transition between {\left {Z,N} \right\rangle} and {\left {Z - 2,N - 2} \right\rangle} even-even nuclei via the 1^{+} states of {\left {Z - 1,N - 1} \right\rangle} intermediate nuclei depends only on the superfluid parameters.

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Radiation Transfer For Exponential C(X), Fatma Erdoğan Jan 2002

Radiation Transfer For Exponential C(X), Fatma Erdoğan

Turkish Journal of Physics

The emergent flux for radiation transfer in inhomogeneous half-space for exponential c(x) = 1 + ke^{-mx}/1 + be^{-mx} is obtained by using Modified-Eddington method, where m, b, k are constants. As a result of this work, angular flux is obtained in terms of Jacobi polynomials.

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Monte Carlo Simulation Of Electron Transport In Insb, Ö. Özbaş, M. Akarsu Jan 2002

Monte Carlo Simulation Of Electron Transport In Insb, Ö. Özbaş, M. Akarsu

Turkish Journal of Physics

Transport properties of indium antimonide in an electric field have been calculated at 77 K. The calculation shows that ionized impurity scattering plays a dominant role in InSb at low electric field. The mobility, mean energy, and drift velocity are calculated as a function of the electric field strength, and comparison is made with previous theoretical results. Types of the scattering mechanisms and percentage of each mechanism in the total scattering events are determined.

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The Spectral Properties Of Two Interacting Electrons In A Quantum Dot, Mohammad Elsaid Jan 2002

The Spectral Properties Of Two Interacting Electrons In A Quantum Dot, Mohammad Elsaid

Turkish Journal of Physics

The shifted 1/N expansion method is used to study the spectral properties of two interacting electrons confined in a QD, under influence of a uniform magnetic field of arbitrary strength. We give explanation to the transitions in the spin and angular momenta of the QD ground state as the magnetic field sweeps. The electron addition energy is also calculated. Based on different comparisons , the shifted 1/N expansion method gives very good result against various methods used to study the spectra of a two electron QD.

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Study Of The Effectiveness Of Various Solar Wind Parameters In The Development Of Geomagnetic Storms During Interplanetary Events, -- Badruddin Jan 2002

Study Of The Effectiveness Of Various Solar Wind Parameters In The Development Of Geomagnetic Storms During Interplanetary Events, -- Badruddin

Turkish Journal of Physics

We have selected some interplanetary events responsible for geomagnetic disturbances of varying magnitude, fairly different from one another. We then tried to find the heliospheric structure (e.g. shock/sheath and/or CME/magnetic cloud) responsible for individual disturbances. We have discussed and inter-compared these structures in their plasma and field parameters as well as in their geomagnetic effects. As a parameter for geomagnetic disturbance we have chosen index Dst, to compare it with variations in field and plasma to heliospheric response structures. We considered parameters such as total field strength, its north-south component, solar wind density, temperature and velocity. In addition, we have …

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Effect Of The Oxygen/Halogen Ratio On The Physical Properties Of Some Sodium-Boro-Vanadate Glasses, Ahmed Gamal El-Din Mostafa Jan 2002

Effect Of The Oxygen/Halogen Ratio On The Physical Properties Of Some Sodium-Boro-Vanadate Glasses, Ahmed Gamal El-Din Mostafa

Turkish Journal of Physics

Four different glass systems of the sodium boro-vanadate type containing halogen ions, were prepared by melting at 1000°C for three hours and annealed at 300°C. These glasses were investigated using dc conductivity, density, molar volume and magnetic susceptibility measurements. It was found that the activation energy shows a decrease as the halogen ions were increased, which was attributed to the increase in the mobility of sodium ions and the gradual formation of some terminal non-bridging halogens, in addition to the electron hopping between the different oxidation states of vanadium. The activation energy values for glasses containing iodine ions was less …

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Paramagnetic Defects In \Gamma-Irradiated, Pure And Doped (With As, Cl And Br) Selenium, Ibrahimgizi Salima Mekhtieva, Ibrahimogli Namig Ibragimov, Isaogli Abasat Isaev, Zeinalogli Vasif Zeinalov, Arifogli Eldar Mamedov Jan 2002

Paramagnetic Defects In \Gamma-Irradiated, Pure And Doped (With As, Cl And Br) Selenium, Ibrahimgizi Salima Mekhtieva, Ibrahimogli Namig Ibragimov, Isaogli Abasat Isaev, Zeinalogli Vasif Zeinalov, Arifogli Eldar Mamedov

Turkish Journal of Physics

This paper presents results of an EPR spectrum investigation of \gamma-irradiated (Co^{60} dose 10^{7} Rad) glasses Se, SeCl_{x}, Se_{0.95}As_{0.05}Cl_{x} and Se_{0.95}As_{0.05}Br_{x} (x=0.001--0.1) at 77 K. An analysis of spectra reveals that two types of paramagnetic radiation-induced defects arise (broken bonds localized on Se and As atoms) from the irradiation of such chalcogenide glasses.

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Monitoring The Effect Of Recrystallization And Quenching In Almg_{X} Alloy By Pat, A. Ashour, Nour Zaki El-Said, Emad A. Badawi Jan 2002

Monitoring The Effect Of Recrystallization And Quenching In Almg_{X} Alloy By Pat, A. Ashour, Nour Zaki El-Said, Emad A. Badawi

Turkish Journal of Physics

Positron annihilation technique (PAT) lifetime measurements have been carried out on AlMg_{x} samples (x = 0.23, 0.85, 1.27 and 1.4 at %) with point defects and dislocations introduced by plastic deformation at room temperature. Clustering of vacancies was observed by quenching using PAT. The samples were annealed at 573 K for 12 hours to homogenize and divided into two sets. The first set of AlMg_{x} (x = 0.23, 0.85 and 1.4 at %) was deformed to 10, 25 and 35% thickness reduction. Isochronal annealing was studied in the range of 300-550 K. In the second set of measurements, AlMg_{x} (x …

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Measurement Of Photon-Induced K X-Rays Production Cross Sections For Elements With 62 \Le Z \Le 74, Sabri̇ye Seven Jan 2002

Measurement Of Photon-Induced K X-Rays Production Cross Sections For Elements With 62 \Le Z \Le 74, Sabri̇ye Seven

Turkish Journal of Physics

X-ray production cross sections of K\alpha_{1}, K\alpha_{2}, K\beta'_{1} (= K\beta {\ss}_{1} + K\beta_{3} + K\beta_{5}) and K\beta'_{2} (= K\beta_{2} + K\beta_{4} + transitions from higher levels) lines have been measured and theoretically calculated for six elements with 62 \le Z \le 74 at excitation energy of 78.706 keV, the weighted avarage of K conversion x-rays emitted from Bi. The experimental results were compared with theoretically predicted values based on relativistic Hartree-Slater and Hartree-Fock theories, a comparison that was found to be in good agreement to within the experimental uncertainties.

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The Sensitivity Of C\Rightarrow U \Gamma Decay In The Gluino-Axion Model, Müge Boz Jan 2002

The Sensitivity Of C\Rightarrow U \Gamma Decay In The Gluino-Axion Model, Müge Boz

Turkish Journal of Physics

The sensitivity of c\rightarrow u \gamma decay in the recently proposed gluino-axion model is analyzed for a light sbottom in a restricted parameter space. The decay rate enhances up to 3\%$ with respect to the SM result in a moderate range of \tan\beta values.

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Stimulated Polarization In \Bf Linbo_{3} And \Bf Ba_{2}Nanb_{5}O_{15} Crystals, Süleyman Çabuk, Amirullah Mamedov Jan 2002

Stimulated Polarization In \Bf Linbo_{3} And \Bf Ba_{2}Nanb_{5}O_{15} Crystals, Süleyman Çabuk, Amirullah Mamedov

Turkish Journal of Physics

Thermally Stimulated Conductivity (TSC) and thermoelectret state in LiNbO_{3} and Ba_{2}NaNb_{5}O_{15} were measured as a function of temperature and time in dark and under UV excitation at liquid nitrogen temperature. Effect of polarization and the other external influences on thermoelectret were investigated. The thermal activation energy levels of traps were determined from TSC measurements as well as parameters (electric field, temperature, etc.) which are necessary for characterizing thermoelectrets were obtained.

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Near Bandedge Optical Absorption Processes In Semi Insulating And N-Type Gaas, Tacetti̇n Yildirim, Sebahatti̇n Tüzemen, Seydi̇ Doğan, Beki̇r Gürbulak, Aytunç Ateş, Muhammet Yildirim Jan 2002

Near Bandedge Optical Absorption Processes In Semi Insulating And N-Type Gaas, Tacetti̇n Yildirim, Sebahatti̇n Tüzemen, Seydi̇ Doğan, Beki̇r Gürbulak, Aytunç Ateş, Muhammet Yildirim

Turkish Journal of Physics

Near bandedge optical absorption processes in semi-insulating (SI) GaAs and Te-doped n-type GaAs crystals were investigated in the temperature range 10--300 K. We observed absorption peaks whose maximum energies E_{m}, ranging from 1.498 to 1.485 eV decrease as the temperature increases from 10 K to 100 K. The peaks for both SI and n-type GaAs disappeared above 100 K. Extrapolating the graphs of E$_{g}-E_{m} versus temperature, we observed that near bandedge absorption is overlapped by the conduction band at about 220 K and 260 K for n-type and SI samples, respectively. Furthermore, we demonstrated that the absorption in the region …

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Kinetics Of Light-Induced Metastable Defect Creation And Annealing In A-Si:H, Alp Osman Kodolbaş, Aynur Eray, Özcan Öktü Jan 2002

Kinetics Of Light-Induced Metastable Defect Creation And Annealing In A-Si:H, Alp Osman Kodolbaş, Aynur Eray, Özcan Öktü

Turkish Journal of Physics

Constant Photocurrent Method (CPM) and steady state photoconductivity measurements are used to investigate the creation of light-induced metastable defects in a-Si:H at room temperature and their annealing. Light-induced metastable defect concentration N$_{d}$ varies with exposure time t_{e}as t_{e}^{r} with r=0.34\ pm 0.02, as expected from the recombination induced weak bond breaking model [1]. The validity of a stretched exponential model is also studied [2]. From the annealing experiments, the distribution of thermal annealing activation energies is calculated following the method proposed by Hata and Wagner [3]. Defects created at room temperature show a narrow distribution of annealing activation energies peaking …

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The Contributions Of Anomalous Magnetic Moment To Relativistic Landau Orbits, Ali̇ Havare, Nuri̇ Ünal Jan 2002

The Contributions Of Anomalous Magnetic Moment To Relativistic Landau Orbits, Ali̇ Havare, Nuri̇ Ünal

Turkish Journal of Physics

In this work, the contributions of anomalous magnetic moment to relativistic Landau orbits are calculated by the method of self-field quantum electrodynamics. In addition to contributions from positive energy states new terms from negative energy states that have not been taken into account before are now also included. Contributions from these terms are found to be in the same order as positive terms.

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The Determination Of Thermal Annealing Effect On A-Si:H Films Coated On Glass And On Single Crystalline Of Silicon, Necmi̇ Seri̇n, Tülay Seri̇n, Ali̇ Riza Özdemi̇r, Bora Alkan, Çeli̇k Tarimci, Basri̇ Ünal Jan 2002

The Determination Of Thermal Annealing Effect On A-Si:H Films Coated On Glass And On Single Crystalline Of Silicon, Necmi̇ Seri̇n, Tülay Seri̇n, Ali̇ Riza Özdemi̇r, Bora Alkan, Çeli̇k Tarimci, Basri̇ Ünal

Turkish Journal of Physics

The aim of this study was to examine the effect of thermal annealing on hydrogenated intrinsic amorphous silicon a-Si:H films. Hydrogenated intrinsic amorphous films were seperately coated on glass and single cyrstalline silicon substrates by means of d.c. magnetron sputtering technique. a-Si:H/glass and a-Si:H/c-Si samples were annealed in the temperature range of 23-250^oC, 23-200^oC and 600-1050^oC, respectively. The effect of annealing on the a-Si:H films were examined by means of Infrared vibrational transmittance spectrum technique (IR) in the wavenumber range 4000-400 cm^{-1} and Scanning Electron Microsope (SEM). The results were interpreted in terms of hydrogen diffusion.

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Preparation And Anisotropic Elastic Property Of Bi-Sr-Ca-Cu-O Whiskers, Khaliq A. Chaudhary, M. Arshad Choudhry Jan 2002

Preparation And Anisotropic Elastic Property Of Bi-Sr-Ca-Cu-O Whiskers, Khaliq A. Chaudhary, M. Arshad Choudhry

Turkish Journal of Physics

Flexible and superconducting Bi-Sr-Ca-Cu-O whiskers have been prepared by sintering the melt-quenched glassy powder at 830^oC in oxygen atmosphere. X-ray diffraction and a.c. susceptibility measurements reveal that the whiskers belong to 2212 phase with T_{c} = 79k. The whiskers possess high strength and flexibility along c-axis but were found to be weak and brittle when bent normal to the c-axis. The anisotropic micromechanical elastic property of the whiskers have been demonstrated under a low power optical microscope.

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Filamentation Of Light Emission In An Infrared-Visible Image Converter With A Semiconductor Photodetector, Hi̇lal Yücel Kurt, H. S. Kiymaz, B. G. Salamov, K. Çolakoğlu Jan 2002

Filamentation Of Light Emission In An Infrared-Visible Image Converter With A Semiconductor Photodetector, Hi̇lal Yücel Kurt, H. S. Kiymaz, B. G. Salamov, K. Çolakoğlu

Turkish Journal of Physics

This work studies the light emission patterns associated with the spatial modulation of the transversal distribution of the current density in a converter cell with a GaAs semiconductor cathode. Such light emission exhibits spatial structures of current filaments depending on the feeding voltage, illumination intensity, gas pressure and the surface treatment of the electrodes. When the current is increased above the stable limit, breakdown or small current filamentations begin. However, n-GaAs exhibits an S-shaped current-density-field relation due to impact ionization of carriers from shallow donors into the conduction band under high electric fields. The assessment of the filament formation is …

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A Method For Identifying Gluon Jets With High Purity In 3-Jet Hadronic Z Decays, Ayda Beddall Jan 2002

A Method For Identifying Gluon Jets With High Purity In 3-Jet Hadronic Z Decays, Ayda Beddall

Turkish Journal of Physics

A method for identifying gluon jets with very high purity is presented and the performance evaluated. Quark and gluon jets from Monte Carlo simulated Hadronic Z decays are identified by energy ordered jets and applying heavy flavour tagging. It is shown that quark and gluon jets can be identified with a purity of about 98%.

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The Investigation Of The E2/M1 Multipole Mixing Ratios And Deformation Parameters Of Electromagnetic Transitions In Decay Of ^{156}Gd, Mehmet Baylan, İhsan Uluer Jan 2002

The Investigation Of The E2/M1 Multipole Mixing Ratios And Deformation Parameters Of Electromagnetic Transitions In Decay Of ^{156}Gd, Mehmet Baylan, İhsan Uluer

Turkish Journal of Physics

The extended Rotation -- Vibration Model (RTV) containing different deformations for protons and neutrons is applied to ^{156}Gd nucleus. Using the Rotation-Vibration Model approach multipole mixing ratios \delta (E2/M1), deformation parameter \beta_{o} , g_{R} factors, and quadrupole moments q_{2} + and q_{o} were calculated.

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Micro-Crystallographic, Optical And Transport Studies Of Cd_{0.7} Zn_{0.3} Se : Sb Thin Films, D. S. Sutrave, G. S. Shahane, V. B. Patil, L. P. Deshmukh, B. D. Sarwade Jan 2002

Micro-Crystallographic, Optical And Transport Studies Of Cd_{0.7} Zn_{0.3} Se : Sb Thin Films, D. S. Sutrave, G. S. Shahane, V. B. Patil, L. P. Deshmukh, B. D. Sarwade

Turkish Journal of Physics

Cd_{1-x}Zn_{x}Se thin film structures doped with various concentrations of trivalent antimony were chemically deposited onto glass-substrates. These structures were then characterised through the XRD, SEM, optical and electrical characterization techniques. The X-ray diffractograms of both as-prepared and Sb-doped samples were obtained and analysed. The analysis revealed that the samples are microcrystalline over the whole range of the doping concentration (0 to 2 mol %). It is striking that the intensities of hexagonal and cubic reflections of CdSe went on increasing with doping concentration upto 0.1 mol % and decreased with further increase in Sb^{3+} content in the film whereas peak …

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Relations For Different Resonators Of Nd:Glass And Nd:Yag Lasers, Erol Taşal, M. Selami̇ Kiliçkaya Jan 2002

Relations For Different Resonators Of Nd:Glass And Nd:Yag Lasers, Erol Taşal, M. Selami̇ Kiliçkaya

Turkish Journal of Physics

Simple relations in terms of effective g parameters are given for linear resonators that contain laser rods with curved endfaces and for symmetrical and asymmetric ring resonators of Nd:Glass and Nd:YAG lasers. The equivalence relationships of thick and thin lenses have been applied.

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Urbach's Rule And Optical Properties For Tlgas_{2}, Aytunç Ateş, Beki̇r Gürbulak, Muhammet Yildirim, Seydi̇ Doğan, Songül Duman, Tacetti̇n Yildirim, Sebahatti̇n Tüzemen Jan 2002

Urbach's Rule And Optical Properties For Tlgas_{2}, Aytunç Ateş, Beki̇r Gürbulak, Muhammet Yildirim, Seydi̇ Doğan, Songül Duman, Tacetti̇n Yildirim, Sebahatti̇n Tüzemen

Turkish Journal of Physics

Absorption measurements were carried out on TlGaS_{2} sample in the temperature range between 10 and 320 K in 10 K steps. There is an abrupt change in the Urbach energy at 180 K and 280 K and steepness parameter at 120 K and 220 K .Obtained from the changing of the Urbach energy, these may be phase transition temperatures. The phonon energies calculated for TlGaS_{2} is 19.7 \pm 5 meV.

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On Numerical Simulations Of Composite Dielectrics In Thermally Stimulated Conditions, Eni̇s Tuncer, Stanislaw M. Gubanski Jan 2002

On Numerical Simulations Of Composite Dielectrics In Thermally Stimulated Conditions, Eni̇s Tuncer, Stanislaw M. Gubanski

Turkish Journal of Physics

A binary composite system with particulated inclusions was considered. First, thermally stimulated depolarization ({\sc tsd}) currents of the system were simulated by altering different parameters of the {\sc tsd} current equation, {\em i.e.}, intrinsic dielectric properties of constituents, conductivity of inclusions, heating rate and activation energy of inclusion conductivity and shape of inclusions. Two different methods of finding the activation energy of {\sc tsd} processes from the simulated {\sc tsd} currents were discussed. Second, we have included the Monte Carlo technique by assuming that the shape factor of inclusions were distributed. These simulations have shown that if the inclusions were …

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The B --> S G G Decay In The General Two Higgs Doublet Model, E. O. İltan Jan 2002

The B --> S G G Decay In The General Two Higgs Doublet Model, E. O. İltan

Turkish Journal of Physics

We study the decay width of the inclusive process b --> s g g in the two Higgs doublet model with three-level flavor changing neutral currents (model III). We analyse the dependencies of the differential decay width to the s- quark energy E_s and model III parameters, charged Higgs mass m_H_{^{±}} and Yukawa coupling \bar{\xi}_{N,bb}^D. We observe that there exist a considerable enhancement in the decay width for the relevant process. This enhancement can be reduced by choosing C_7^{eff} as negative or increasing the lower bound of m_H_{^{±}} to the large values. This is an interesting result which gives an …

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Spin Polarized Cold And Hot Dense Neutron Matter, S. A. Moharrm, Azza O. El-Shal Jan 2002

Spin Polarized Cold And Hot Dense Neutron Matter, S. A. Moharrm, Azza O. El-Shal

Turkish Journal of Physics

The Thomas-Fermi (TF) model is used to calculate the equation of state of thermal polarized neutron matter. The properties of cold and hot neutron matter have been investigated. A realistic density-dependent M3Y effective nucleon-nucleon (NN) interaction where the Yukawa strengthes are based on the G-matrix of the Paris interaction has been used. Special attention is devoted to the effect of the spin excess parameter on these properties. Moreover, the effect of some realistic density dependence has been studied. The results obtained are in reasonable agreement with previous theoretical estimates using different methods of calculation.

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Radial And Nonradial Oscillations Of 63 Her (Hd155514 = Hr6391), Ri̇kkat Ci̇velek, Ni̇lgün Kiziloğlu, Hali̇l Kirbiyik Jan 2002

Radial And Nonradial Oscillations Of 63 Her (Hd155514 = Hr6391), Ri̇kkat Ci̇velek, Ni̇lgün Kiziloğlu, Hali̇l Kirbiyik

Turkish Journal of Physics

An attempt has been made toward explaining the observed frequencies in 63 Her. A sequence of evolutionary models have been calculated up to a point where stellar parameters match the observed luminosity and effective temperature of 63 Her. Radial and nonradial oscillations frequencies were obtained for a series of masses 1.85, 1.90 and 1.95 M_\odot and eigth models which represent best the pulsations of 63 Her are given in this paper. Calculations are restricted to low harmonic degrees ( l= 0,1,2,3 ). Six of the eigth observed frequencies quoted in literature were obtained. These we obtained for the model of …

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Tsl-Epr Correlation Study Of Lapo_4 : Ce, Tb, B. S. Chakrabarty, K. V. R. Murthy, T. R. Joshi Jan 2002

Tsl-Epr Correlation Study Of Lapo_4 : Ce, Tb, B. S. Chakrabarty, K. V. R. Murthy, T. R. Joshi

Turkish Journal of Physics

Gamma irradiated TSL glow curves of laboratory made phosphor samples of LaPO_{4}:Ce, Tb exhibited one intense peak around 408 K and two smaller peaks around 508 K and 613 K. The spectrum of the first glow peak gives spectral peaks around 480 nm and 540 nm, which can be attributed to the thermal destruction of F^{++} centres and PO_4^{2-} radicals. The luminescense centre has been thought to be Cerium and Terbium ions. The glow peak around 413 K for UV irradiated samples has been attributed to aggregates of dopant ions. The photoluminescence study of the samples exhibited one intense peak …

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Structural Analysis Of A Gaas/Al_Xga_{1-X} As Hot Electron Light Emitter Using Double Axis X-Ray Diffraction, Ali̇ Teke Jan 2002

Structural Analysis Of A Gaas/Al_Xga_{1-X} As Hot Electron Light Emitter Using Double Axis X-Ray Diffraction, Ali̇ Teke

Turkish Journal of Physics

We report on interference peaks in double axis x-ray rocking curves of tunable wavelength hot electron light emitters. The device is based on a p-GaAs and n-Ga_{1-x}Al_xAs heterojunction containing an inversion layer on the p- side, and GaAs quantum wells on the n- side of the junction, a construction known as HELLISH-2 (Hot Electron Light Emitting and Lasing in Semiconductor Heterostructure-Type 2). The interference has been shown to strongly depend on the periodicy of the device structure. Experimental curves are compared with simulated rocking curves. Some structural parameters, such as total epilayer thickness, composition ratio and quantum well width and …

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