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- Thermoluminescence (2)
- A-Si:H (1)
- A-Si:H p-i-n solar cells. (1)
- A. Dark conductivity; B. Photoconductivity; Rf power density; D. Activation energy; E.Hydrogenated amorphous silicon. (1)
- A. High temperature superconductors; B. Hot pressing; C. YBCO; D. I-V; E. AC susceptibility. (1)
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- A. Hydrogenated amorphous silicon nitride; B. Substrate temperature; C. Dark conductivity; D. Photoconductivity; E. Optical gap. (1)
- Acetylene (1)
- Amorphous (a-) Si:H p-i-n solar cells (1)
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- Coriolis force. (1)
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- Cross section. (1)
- Decay width (1)
- Defect structure (1)
- Deformation parameter (1)
- Dielectric constant (1)
- Dielectrics (1)
- Dispersion analysis (1)
- Distribution of annealing activation energies. (1)
- Effects of nonstoichiometry (1)
- Electromagnetic transitions. (1)
- Electron Scattering. (1)
Articles 1 - 30 of 64
Full-Text Articles in Physical Sciences and Mathematics
The Sensitivity Of C\Rightarrow U \Gamma Decay In The Gluino-Axion Model, Müge Boz
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.
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
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 …
Temperature Dependence Of Galvanomagnetic Properties For Lightly Doped N-Type Si, Aytunç Ateş, Beki̇r Gürbulak, Seydi̇ Doğan, Muhammet Yildirim, Sebahatti̇n Tüzemen
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 …
A Method For Identifying Gluon Jets With High Purity In 3-Jet Hadronic Z Decays, Ayda Beddall
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%.
The Investigation Of The E2/M1 Multipole Mixing Ratios And Deformation Parameters Of Electromagnetic Transitions In Decay Of ^{156}Gd, Mehmet Baylan, İhsan Uluer
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.
Relations For Different Resonators Of Nd:Glass And Nd:Yag Lasers, Erol Taşal, M. Selami̇ Kiliçkaya
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.
Effect Of The Zn Concentration On The Characteristic Parameters Of Zn_{X}Cd_{1 - X}S Thin Films Developed By Spraying Pyrolysis Method Under The Nitrogen Atmosphere, Meti̇n Bedi̇r, Refi̇k Kayali, Mustafa Öztaş
Effect Of The Zn Concentration On The Characteristic Parameters Of Zn_{X}Cd_{1 - X}S Thin Films Developed By Spraying Pyrolysis Method Under The Nitrogen Atmosphere, Meti̇n Bedi̇r, Refi̇k Kayali, Mustafa Öztaş
Turkish Journal of Physics
The electronic and optical properties of Zn_{x}Cd _{(1- x)}S thin films (0.0 \le x \le 0.7) fabricated using the chemical spray method have been investigated in nitrogen atmosphere. The films are deposited on glass substrates at 420^oC substrate temperature. The related optical data are recorded in the wavelength range 200-700 nm. In addition, the absorption coefficient is determined and correlated with the photon energy in order to estimate the direct transition energy bandgap. The crystallite size and degree of preferential orientation were found to decrease with the increase of x and to improve upon annealing in vacuum at \cong 600^oC. …
The B --> S G G Decay In The General Two Higgs Doublet Model, E. O. İltan
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 …
Spin Polarized Cold And Hot Dense Neutron Matter, S. A. Moharrm, Azza O. El-Shal
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.
Tsl-Epr Correlation Study Of Lapo_4 : Ce, Tb, B. S. Chakrabarty, K. V. R. Murthy, T. R. Joshi
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 …
Contribution To The Relationship Between Solar Radiation And Sunshine Duration In The Tropics: A Case Study Of Experimental Data At Ilorin, Nigeria, Sunday O. Udo
Turkish Journal of Physics
From monthly average daily values of clearness index and relative sunshine spanning a period of two years, two equations (linear and quadratic) of the Angstrom-Prescott model have been developed for the estimation of global solar irradiation at Ilorin (Lat. 8°32'N, Long. 4°34'E), a tropical location. Comparison of the regression coefficients of the linear type model showed that the values are quite consistent with those quoted in the literature for the Tropics. The predictive efficiencies of these two models are also compared with those which are believed to be applicable globally, and those developed for the Nigerian environment. Although some of …
Effects Of Substrate Temperature On Properties Of A-Sin_X:H Films, Tayyar Güngör, Hüseyi̇n Tolunay
Effects Of Substrate Temperature On Properties Of A-Sin_X:H Films, Tayyar Güngör, Hüseyi̇n Tolunay
Turkish Journal of Physics
Hydrogenated amorphous silicon nitride films were prepared in an rf glow-discharge system by the decomposition of silane + nitrogen gas mixture at various substrate temperatures. The effects of substrate temperature on the electrical and optical properties of the films have been studied.
Monte Carlo Simulation Of Electron Transport In Insb, Ö. Özbaş, M. Akarsu
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.
The Ibm-2 Study For Some Even - Even Platinum Isotopes, Mehmet Baylan, Mehmet Altay Atlihan
The Ibm-2 Study For Some Even - Even Platinum Isotopes, Mehmet Baylan, Mehmet Altay Atlihan
Turkish Journal of Physics
The structure of some even -- even Pt isotopes have been studied within the framework of the interacting boson model. The B(E2), B(M1) and Q(I) values of the above nuclei have been calculated. The numerical results obtained for Pt have been compared with the previous experimental and theoretical values obtained on the basis of the interacting boson model (IBA-2).
The Single Step Vmhnc Calculations For Liquid Alkali Metals In The Inverse Problem, Serap Şentürk Dalgiç, Seyfetti̇n Dalgiç, Mehmet Tomak
The Single Step Vmhnc Calculations For Liquid Alkali Metals In The Inverse Problem, Serap Şentürk Dalgiç, Seyfetti̇n Dalgiç, Mehmet Tomak
Turkish Journal of Physics
An effective pair potential \phi (r) for liquid alkali metals close totheir melting points is extracted from an experimental structure factor using the inverse method based on the variational modified hypernetted-chain integral equation theory of liquids (VMHNC). The first order pair potential according to the procedure suggested by de Angelis and March is also presented for comparison. It has been found that the inverted pair potentials of liquid alkali metals scale well.
Single And Double-Layer Antireflection Coatings On Silicon, İpek Gi̇rgi̇n Kavakli, Kayhan Kantarli
Single And Double-Layer Antireflection Coatings On Silicon, İpek Gi̇rgi̇n Kavakli, Kayhan Kantarli
Turkish Journal of Physics
In this study, the effect of single and double-layer thin film coatings on the reflectance spectrum of silicon surfaces has been investigated. Thin film coatings have been prepared by vacuum evaporation of the materials with suitable refractive index. Reflectance measurements in the visible and near infrared have shown that the coated samples acquire antireflection properties. Thickness and wavelength dependence of the antireflection properties of SiO, CeO_2 and ZnS single-layer coatings with optical thickness of one quarter wavelength has been studied. In double-layer coatings, a thin film of SiO, CeO_2 and ZnS with optical thickness of quarter wavelength were used as …
The Effects Of Nonstoichiometry In High - T_C Superconducting Properties Of Yba_2cu_{3 + X}O_{7 - \Delta}, Beniah Ndudim Onwuagba
The Effects Of Nonstoichiometry In High - T_C Superconducting Properties Of Yba_2cu_{3 + X}O_{7 - \Delta}, Beniah Ndudim Onwuagba
Turkish Journal of Physics
Polycrystalline samples of high T_c superconductor YBa_2Cu_{3 + x}O_{7 - \delta} with 0 \leqslant x \leqslant 0.5 were grown. The effects of nonstoichiometry on the resistance slope above transition temperature T_c and X-ray diffraction patterns for these samples were investigated. In the diffraction patterns obtained, apart from some new features in the peaks, these polycrystalline samples show predominantly 123 phase.
Some Characteristic Properties, Vithal Bhivaba Pujari, V. B. Gaikwad, E. U. Masumdar, P. D. More, L. P. Deshmukh
Some Characteristic Properties, Vithal Bhivaba Pujari, V. B. Gaikwad, E. U. Masumdar, P. D. More, L. P. Deshmukh
Turkish Journal of Physics
This paper presents some information regarding (Cd, Hg) Se materials synthesized by a simple chemical growth process and the structural, optical and electrical transport properties. The growth of these films depends on various preparative parameters and deposition conditions such as concentration of the starting materials, pH, temperature, time, speed of mechanical churning, etc., and the reaction kinetics suggests that the films grow into two different phases: one, initialy an almost linear phase; and second, a saturation phase. The deposits were analysed chemically and by an EDS techniques. It has been seen that more than 70% of the materials taken in …
Mathematical Modeling Of Plasmachemical Processes, Meli̇k-Aslanova Tamilla
Mathematical Modeling Of Plasmachemical Processes, Meli̇k-Aslanova Tamilla
Turkish Journal of Physics
In this research, we studied the kinetics of plasmachemical processes in quasiequilibrium and nonequilibrium conditions. The example of methane conversion into acetylene showed that the most efficient plasmachemical process may be achieved under nonequilibrium conditions, especially, when the reaction was stimulated by vibrational excitation of molecules.
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
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.
Monitoring The Effect Of Recrystallization And Quenching In Almg_{X} Alloy By Pat, A. Ashour, Nour Zaki El-Said, Emad A. Badawi
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 …
On The Numerical Solution And Limitations Of Energy Equation For Vertical Bridgman System With Varying Temperature Gradient At The Boundary, Ergün Taşarkuyu, Evren Akar, Bülent Gülteki̇n Akinoğlu
On The Numerical Solution And Limitations Of Energy Equation For Vertical Bridgman System With Varying Temperature Gradient At The Boundary, Ergün Taşarkuyu, Evren Akar, Bülent Gülteki̇n Akinoğlu
Turkish Journal of Physics
In vertical Bridgman crystal growth systems solid-liquid interface shape is one of the most important factors affecting the product quality. Most of the theoretical studies to determine the interface shape consider the numerical solution to the heat-conduction and the energy equation. The purpose of this work is to present and discuss a numerical solution to the energy equation (also called the convection-diffusion equation) for a vertical Bridgman system with varying temperature gradient at the boundary. Different system parameters are examined and the importance of the pulling rate for different materials in the utilization of the energy equation is emphasized. The …
Excess Properties Of Alcohol - Water Systems At 298.15 K, Hülya Yilmaz
Excess Properties Of Alcohol - Water Systems At 298.15 K, Hülya Yilmaz
Turkish Journal of Physics
Dielectric constants \varepsilon, viscosities \eta, refractive indices n and densities d have been measured over the entire mole fraction range for the water - methyl, ethyl, n-propyl alcohol binary systems at 298.15 K. From the experimental data excess dielectric constants \varepsilon^E, excess viscosities \eta^E and Kirkwood correlation factors g_k have been calculated and studied. Their behaviour suggests the existence of intermolecular interactions and plotted curves show that excess dielectric constant and g_k values decrease with the increasing of carbon atom number, while excess viscosity increases.
The Electron-Photon Coincidence Method And Its Application To Excitation Of The 2p State Of Atomic Hydrogen, Hüseyi̇n Ali̇ Yalim, Albert Crowe
The Electron-Photon Coincidence Method And Its Application To Excitation Of The 2p State Of Atomic Hydrogen, Hüseyi̇n Ali̇ Yalim, Albert Crowe
Turkish Journal of Physics
Early measurements of atomic excitation by electron scattering observed either the scattered electron or decay photon. An excited state can not be completely defined by such experiments due to loss of information. Therefore a new method was developed in the early 70's called the correlation method. The new correlation method involves the detection of both the scattered electron and photon arising from the same collision using coincidence techniques. This method enables a full description of an excited state. In this paper, we give a discussion of to the method and its application to excitation of the 2p state of atomic …
Short-Range Correlations In Coupled Quantum-Wire Systems, A. Yurtsever, B. Tanatar
Short-Range Correlations In Coupled Quantum-Wire Systems, A. Yurtsever, B. Tanatar
Turkish Journal of Physics
We study the contact values of the inter-wire pair-correlation function in electron-electron and electron-hole double-wire systems. For this purpose the ladder approximation as generalized to multicomponent systems is used. The ladder approximation yields positive values for the inter-wire g_{ee}(0) and g_{eh}(0) for all values of the density parameter r_s and distance d between the wires. This allows us to infer possible instabilities in the system more reliably compared to other approaches. We also investigate the effects of quantum-wire width and screening on the inter-wire pair-correlation functions. PACS numbers: 05.30.Fk, 73.20.Dx, 71.45.Gm, 73.40.Kp
Interface Roughness-Induced Intrassubband Scattering In A Quantum Well Under An Electric Field, Guseyn Behbudoglu Ibragimov
Interface Roughness-Induced Intrassubband Scattering In A Quantum Well Under An Electric Field, Guseyn Behbudoglu Ibragimov
Turkish Journal of Physics
The scattering rates in the lowest subband in a quantum well are calculated for interface roughness scattering when an electric field is applied perpendicular to the layer plane. It is found that the interface roughness scattering rate increases with increase in the electric field. The electric field changes the interface roughness scattering rates drastically in thick QWs compared with those for the zero-field case. This behaviour in the scattering rate gives a new degree of freedom in regions of interest in device applications.
Off-Diagonal Matrix Elements And Sum Rules Involving Coulomb And Isotropic Oscillator Functions, Harry A. Mavromatis
Off-Diagonal Matrix Elements And Sum Rules Involving Coulomb And Isotropic Oscillator Functions, Harry A. Mavromatis
Turkish Journal of Physics
Off-diagonal matrix elements and sum rules for the Coulomb and isotropic oscillator systems are obtained from a study of relations between the off-diagonal matrix elements of a general recursion relation.
Determination Of The Trapping Parameters Of Zns Thin Films Developed By Chemical Spraying Technique, A. Necmetti̇n Yazici, Mustafa Öztaş, Meti̇n Bedi̇r, Refi̇k Kayali
Determination Of The Trapping Parameters Of Zns Thin Films Developed By Chemical Spraying Technique, A. Necmetti̇n Yazici, Mustafa Öztaş, Meti̇n Bedi̇r, Refi̇k Kayali
Turkish Journal of Physics
In this study, the thermoluminescence (TL) glow curves of ZnS thin films developed using chemical spraying technique were carefully investigated and its kinetic parameters were determined with a specially developed computer program. The results of investigations have shown that the trapping states of ZnS thin films could not be analysed by a well-known Randall-Wilkins (RW) or General-Order (GO) models. A detailed investigation of experimental results has indicated that the trapping states have a form that is best described by a distribution of energies. After the comparison of the experimental glow curves of ZnS thin films with theoretically generated glow curves, …
Effects Of The Back Reflector On The Optical Enhancement Factor And Quantum Efficiency Of A-Si:H P-I-N Solar Cells, Ruhi̇ Kaplan, Bengü Kaplan
Effects Of The Back Reflector On The Optical Enhancement Factor And Quantum Efficiency Of A-Si:H P-I-N Solar Cells, Ruhi̇ Kaplan, Bengü Kaplan
Turkish Journal of Physics
The effect of tin oxide (SnO_2) texture and back reflector (BR) on optical enhancement factor has been extensively investigated in a series of 4 a-Si:H p-i-n solar cells. The internal quantum efficiency QE in the wavelength range 550--750 nm has been analyzed using an optical model. The optical enhancement factor m, which is a wavelength-dependent fitting parameter, represents the increase in optical pathlength relative to the i-layer thickness. Our solar cells, at low or high haze SnO_{2} with an Al BR, have negligible optical enhancement, m < 1.5, representing failure to obtain multiple reflections. This is consistent with large parasitic absorption at the Al/Si interface. Our solar cells at high haze SnO_{2} with ZnO/Al or ZnO/Ag BRs have peak values of m \sim 3-4, with ZnO/Ag having slightly larger values than ZnO/Al. The maximum values of m , and thus the QE increase with reflectivity of the BR, indicates that efficient light trapping needs a very reflective BR to minimize parasitic absorption losses with each pass.
Formation Energy In Al-Mg Alloy By Positron Annihilation Lifetime Technique (Palt), Mamduh Abedl-Rahman, Emad A. Badawi, Essmat Mahmoud Hassan, Gamal Yahya
Formation Energy In Al-Mg Alloy By Positron Annihilation Lifetime Technique (Palt), Mamduh Abedl-Rahman, Emad A. Badawi, Essmat Mahmoud Hassan, Gamal Yahya
Turkish Journal of Physics
The propose of the present work is to study the interaction of positrons with quenched-in defects and clustered atoms to estimate formation enthalpy in series 50xx of commercial Al-Mg alloys, namely, 5049, 5051,5052 and 5083 at various concentrations: 1.9, 2.09, 2.46 and 4.44 wt % of Mg, respectively. Typically additional impurities were mainly Si, Fe, Cu, Cr and Ti. The monvacancy formation energy of Al-Mg alloys was measured from a trapping model analysis of the T-dependence of the positron lifetime.