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Comparison Of Metallicities Adopted For The Synthetic Ubv Photometry With Those Evaluated By Means Of Rgu Photometry, S. Karaali̇, S. Güngör, Y. Karataş Jan 1998

Comparison Of Metallicities Adopted For The Synthetic Ubv Photometry With Those Evaluated By Means Of Rgu Photometry, S. Karaali̇, S. Güngör, Y. Karataş

Turkish Journal of Physics

Comparison of metallicities adopted for synthetic UBV photometry with those evaluated by means of RGU photometry for 92 stars is presented. The agreement is only for zero metallicity. The discrepancy increases to low metallicities which cover Intermediate Population II and Population II main-sequence stars. U-G and G-R colour indices are transformed from UBV synthetic data and do not include any observational error. Therefore, the disagreement may originate from a systematic error in the metallicity calibration of relatively metal-poor stars in RGU photometry. Keywords: photometry - stars : abundances - metal-poor.


Magnetic Domain Structures In As-Quenched And Annealed Fe_{78}B_{13}Si_9 Metallic Glass Ribbons, Yücel Bi̇rol Jan 1998

Magnetic Domain Structures In As-Quenched And Annealed Fe_{78}B_{13}Si_9 Metallic Glass Ribbons, Yücel Bi̇rol

Turkish Journal of Physics

Among various soft magnetic materials, ferromagnetic glasses are superior to their crystalline counterparts as they possess no magnetocrystalline anisotropy owing to a non-crystalline structure. However, ferromagnetic glasses carry residual stresses and thus anisotropies of magnetostrictive origin in the as-quenched state. These stresses have an adverse effect on the magnetic softness and should be relieved in order to improve magnetic performance, particularly in magnetostrictive alloys. In the present work, the domain structures of Fe$_{78}$B$_{13}$Si$_9$ metallic glass, a highly magnetostrictive alloy, are characterized in the as-quenched and annealed states. The annealing treatments were carried out over a wide temperature range extending from …


Economic Analysis And Comparison Of Two Solar Energy Systems With Domestic Water Heating Systems, R. Kayali Jan 1998

Economic Analysis And Comparison Of Two Solar Energy Systems With Domestic Water Heating Systems, R. Kayali

Turkish Journal of Physics

In this work, an economic analysis of different types of thermosiphons and geysers and flat plate collectors and solar ponds employeed in conventional solar energy systems used in houses is analized and the results obtained for these systems are compared with each other. These comparisons show that when the inflation rate is 50\% or less solar energy systems are more economical than the other conventional systems, except for conventional systems in which solid fuels are used. If the calculations are done assuming that the consumer credit interest rate varies between 55-70\%, it is seen that solar energy systems will only …


Domain Structures Of Epitaxial Perovskite Ferroelectric Films: Part I. Theory, S. Pamir Alpay, Alexander L. Roytburd Jan 1998

Domain Structures Of Epitaxial Perovskite Ferroelectric Films: Part I. Theory, S. Pamir Alpay, Alexander L. Roytburd

Turkish Journal of Physics

Possible equilibrium domain structures due to elastic interactions between the film and the substrate as a result of a cubic-tetragonal transformation observed in epitaxial perovskite ferroelectric films are analyzed. Domain structures are compared in terms of their elastic energies. The formation of both two- and three-domain states is taken into account. Maps which shows domain stability regions are developed in coordinates of misfit strain and tetragonality of the lattice of the ferroelectric phase.


The Structure Of Liquid Alloys With Chemical Short Range Order, Serap Dalgiç, Seyfettin Dalgiç, Mehmet Tomak Jan 1998

The Structure Of Liquid Alloys With Chemical Short Range Order, Serap Dalgiç, Seyfettin Dalgiç, Mehmet Tomak

Turkish Journal of Physics

We present a study of the structural properties of liquid binary alloys with chemical short range order starting from the effective interatomic pair potentials. The interatomic pair potentials are derived using the second order pseudopotential theory and the static structure is obtained using the modified hypernetted chain approximation. The partial structure factors $S_{ij}(q)$ and the concentration - fluctuation structure factor $S_{cc}(q)$ are calculated to analize the ordering tendencies in a binary alloy. In this work, liquid Li-Mg alloy is studied as a test case. The agreement between theory and experiment is quite good. We conclude that the structural properties of …


Crystal Data For A_3b_5c_9-Type Ternary Compounds, Hüsnü Özkan, Nizami Gasanly, İbrahim Yilmaz, Ali Çulfaz, Vyaceslav Nagiev Jan 1998

Crystal Data For A_3b_5c_9-Type Ternary Compounds, Hüsnü Özkan, Nizami Gasanly, İbrahim Yilmaz, Ali Çulfaz, Vyaceslav Nagiev

Turkish Journal of Physics

X-ray powder diffraction data were obtained for Cu$_3$Ga$_5$Se$_9$, Cu$_3$In$_5$Se$_9$, Cu$_3$In$_5$Te$_9$, Ag$_3$In$_5$S$_9$, Ag$_3$Ga$_5$S$_9$, Ag$_3$In$_5$Se$_9$, and Ag$_3$Ga$_5$Te$_9$ ternary compounds. The data indicate that these compounds crystallize in orthorhombic, monoclinic, orthorhombic, monoclinic, tetragonal, tetragonal, and orthorhombic systems, respectively.


Observation Of Events At Very High Q^2 In E^+P Collisions At Hera, A. Wagner Jan 1998

Observation Of Events At Very High Q^2 In E^+P Collisions At Hera, A. Wagner

Turkish Journal of Physics

Data collected at the $e^+p$ collider HERA at DESY by the experiments H1 and ZEUS have allowed to probe a previously inaccessible domain of very large $Q^2$ in deep-inelastic $ep$ scattering. For $Q^2 > 15000 GeV^2$ both experiments see more events than expected assuming the Standard Model of deep-inelastic scattering. In this report the observed events, the theoretical expectations and their comparison are discussed.


Progess In Photon Colliders, Valery Telnov Jan 1998

Progess In Photon Colliders, Valery Telnov

Turkish Journal of Physics

Last two years were very important in history of a photon colliders. This option is included now in conceptual design reports of the NLC, JLC and TESLA/SBLC projects. All the designs foresee two interaction regions: one for e^+e^- and the second for \gamma\gamma, \gamma e and e^-e^- collisions. This paper is focused on three aspects: 1) arguments for photon colliders; 2) parameters of current projects; 3) ultimate luminosities and energies, new ideas. Recent studies have shown that the main collision effect - coherent pair creation - is suppressed at photon colliders with the energy (2E $


High Luminosity Muon Collider Studies In The U.S.A., Muzaffer Ataç Jan 1998

High Luminosity Muon Collider Studies In The U.S.A., Muzaffer Ataç

Turkish Journal of Physics

Muon colliders as a future collider project in the U.S.A., have attracted many physicists from many institutions in recent years. Workshops and conferences have been held on the subject in the last few years. The studies show that high luminosity circular muon colliders can be built at high luminosities and at high center-of-mass energies. Some aspects of the muon colliders, physics possibilities, background and detector issues will be discussed. Some comparisons between the muon and hadron colliders, and electron-positron colliders, will be made.


Possibility To Measure Polarized Gluon Distribution Via Real Gamma Beam, A. Çeli̇kel Jan 1998

Possibility To Measure Polarized Gluon Distribution Via Real Gamma Beam, A. Çeli̇kel

Turkish Journal of Physics

We propose an experiment to measure the polarized gluon and quark distributions in scattering of polarized real $\gamma$ beam on polarized nuclear target.


Topics On The Physics Potential And Detector Aspects Of The Lc-Hera Ep Collider, A. De Roeck Jan 1998

Topics On The Physics Potential And Detector Aspects Of The Lc-Hera Ep Collider, A. De Roeck

Turkish Journal of Physics

We present a brief account of some physics topics which could be addressed at a collider consisting of the HERA proton ring and the future $e^+e^-$ Linear Collider. A few experimental aspects are also discussed.


Some Physical Problems For Photon Colliders, Ilya F. Ginzburg Jan 1998

Some Physical Problems For Photon Colliders, Ilya F. Ginzburg

Turkish Journal of Physics

Higgs hunting at different colliders is discussed with new possibilities related to photon colliders are discussed. Brief review of discovery potential for new physics is presented.


Search For Supersymmetry At \Gammap - Colliders, A. U. Yilmazer Jan 1998

Search For Supersymmetry At \Gammap - Colliders, A. U. Yilmazer

Turkish Journal of Physics

We discuss the possibility of searching supersymmetry at TeV scale $\gamma p$ colliders proposed recently. Theoretical predictions are derived within the framework of minimal supersymmetric standard model (MSSM) with R-parity conservation. Productions of squarks, gluinos, charginos and neutralinos through the processes $\gamma p\rightarrow\tilde{q}\tilde{w}X$, $\gamma p\rightarrow\tilde{q}\tilde{g}X$, $\gamma p\rightarrow\tilde{q}\tilde{\gamma}X$ (or $\tilde{q}\tilde{z}$) and $\gamma p\rightarrow\tilde{q}\tilde{q}^*X$ are considered. Cross sections for different initial beam polarizations are calculated and it is shown that polarization asymmetries are sensitive to the particle masses. Discovery mass limits of the superpartners are tabulated for various $\gamma p$ colliders at different center of mass energies. The results are compared with …


Tune Shift Limitations For Linac-Ring Type Colliders, Ö. Yavaş Jan 1998

Tune Shift Limitations For Linac-Ring Type Colliders, Ö. Yavaş

Turkish Journal of Physics

Limitations on incoherent and beam-beam tune shift values are calculated by using gaussian beam distribution for linac-ring type $ep$ colliders. The advantage of this machine is achievement of multi TeV center of mass energies in lepton-hadron interactions at sufficiently high luminosities. Tune shift puts a limit on the number of electrons per effective area for the stability of proton beam and, therefore, gives an upper bound for the luminosity.


A Proposal For A Measurement Of The Nucleon Form Factors At An Asymmetric E^+E^- Linac-Ring Collider, R. Baldini, C. Bini, P. Patteri Jan 1998

A Proposal For A Measurement Of The Nucleon Form Factors At An Asymmetric E^+E^- Linac-Ring Collider, R. Baldini, C. Bini, P. Patteri

Turkish Journal of Physics

The neutron electromagnetic form factors have been measured for the first time in the time-like region in the $Q^2$ range between 3.6 and 6 $GeV^2$ by the FENICE experiment. The results show some unexpected features. First the neutron magnetic form factor turns out to be larger than the proton one, the neutron electric form factor being negligible. Then there are indications of a narrow structure very near the $N\overline{N}$ threshold, in the e^+e^- multihadronic annihilation. A new, high statistics experiment is needed to clarify the indications. An asymmetric, unconventional, linac-storage ring collider is proposed, using one of the existing high …


Main Parameters Of \Gammap Colliders, A.K. Çi̇ftçi̇ Jan 1998

Main Parameters Of \Gammap Colliders, A.K. Çi̇ftçi̇

Turkish Journal of Physics

Main parameters of TeV energy $\gamma $p colliders have been investigated for HERA+ SBLC, HERA+TESLA, HERA+e-linac, LHC+TESLA, LHC+CLIC and LHC+$e$ -linac proposals. Luminosity of $\gamma p$ collisions for these colliders are studied in terms of a distance between the conversion region and the collision point.


Main Parameters Of Linac-Ring Type E-Nucleus And \Gamma-Nucleus Colliders, Ş. Turköz Jan 1998

Main Parameters Of Linac-Ring Type E-Nucleus And \Gamma-Nucleus Colliders, Ş. Turköz

Turkish Journal of Physics

The main parameters of linac-ring type e-nucleus and $\gamma $-nucleus colliders are considered. It is shown that the reasonable luminosities at the multi-TeV energies can be achieved.


Electroweak Gauge Boson Production At \Gamma\Gamma Collider, G. Jikia Jan 1998

Electroweak Gauge Boson Production At \Gamma\Gamma Collider, G. Jikia

Turkish Journal of Physics

No abstract provided.


Ordinary And Coherent Bremsstrahlung At Linac-Ring Ep Colliders, V.G. Serbo, D.V. Serebryakova Jan 1998

Ordinary And Coherent Bremsstrahlung At Linac-Ring Ep Colliders, V.G. Serbo, D.V. Serebryakova

Turkish Journal of Physics

The ordinary bremsstrahlung $ep \rightarrow ep\gamma$ can be used at the linac-ring $ep$ colliders for luminosity measurement. It is known that at high energies this process has a large correction due to beam-size effect. We have calculated this effect for $ep$ colliders of the linac-ring type. For the LHC+CLIC collider the correction exceeds 10\% for $E_{\gamma} < 0.95\;E_e$. As a rule, the bremsstrahlung of protons in the $ep$ scattering is not considered due to its small cross section. However, if the photon energy $E_{\gamma}$ becomes small enough, the number of produced photons become large because in this case the radiation is determined by the interaction of a proton with the collective electromagnetic field of the electron bunch. It is coherent bremsstrahlung (CBS). We present the main characteristics of CBS calculated for linac-ring $ep$ colliders. At the LHC+CLIC collider it should be about $1700 \; dE_\gamma /E_\gamma$ photons for a single collision of bunches at $E_\gamma \stackrel{


The Heavy Higgs Effects In The Framework Of Sm, V. Borodulin, G. Jikia Jan 1998

The Heavy Higgs Effects In The Framework Of Sm, V. Borodulin, G. Jikia

Turkish Journal of Physics

No abstract provided.


Discovery Limits For New Resonances At Ep And \Gammap Colliders, M. Kantar Jan 1998

Discovery Limits For New Resonances At Ep And \Gammap Colliders, M. Kantar

Turkish Journal of Physics

We study the resonance production of new particles at Linac-Ring type $ep$ and $\gamma p$ colliders.


A Possibility To Control The Polarization Of High-Energy Photons By Means Of A Laser Beam, G.L. Kotkin, V.G. Serbo Jan 1998

A Possibility To Control The Polarization Of High-Energy Photons By Means Of A Laser Beam, G.L. Kotkin, V.G. Serbo

Turkish Journal of Physics

The elastic light-light scattering below the threshold of the $e^+e^-$ pair production leads to a variation in polarization of hard $\gamma$-quanta traversing without loss a region where the laser light is focused. This effect can be used to control the $\gamma$-quantum polarization. Equations are obtained which determine the variation of Stokes parameters of $\gamma$-quanta in this case, and their solutions are given. It is pointed out that this effect can be observed in the experiment E-144 at SLAC. It should be taken into account and, perhaps, it can be used in experiments at future $\gamma \gamma$ colliders.


Cahit Arf's Contribution To Algebraic Number Theory And Related Fields, Masatoshi G. İkeda Jan 1998

Cahit Arf's Contribution To Algebraic Number Theory And Related Fields, Masatoshi G. İkeda

Turkish Journal of Mathematics

No abstract provided.


Fractional Crystallization And Magma Mingling/Mixing Processes In The Monzonitic Association In The Sw Part Of The Composite Yozgat Batholith (Şefaatli-Yerköy, Sw Yozgat), Si̇bel Tatar, Durmuş Boztuğ Jan 1998

Fractional Crystallization And Magma Mingling/Mixing Processes In The Monzonitic Association In The Sw Part Of The Composite Yozgat Batholith (Şefaatli-Yerköy, Sw Yozgat), Si̇bel Tatar, Durmuş Boztuğ

Turkish Journal of Earth Sciences

The Yozgat batholith takes place in the passive margin of the Anatolide-Pontide convergence system. It includes; syn-collisional S-type, two-mica granites; post-collisional I-type, calcalkaline monzonitic association, and post-collisional, M-type, tholeiitic gabbroic/dioritic association. Among these associations, the monzonitic association is also subdivided into five mapable units such as Cankılı monzogabbro/monzodiorite, Akçakoyunlu quartz monzodiorite, Adatepe quartz monzonite, Yassiagil monzogranite and Karakaya monzogranite. All these subunits, except the Karakaya monzogranite, include K-feldspar megacrysts. These five subunits represent some evidence of fractional crystallization (FC) and magma mingling/mixing processes by means of field, mineralogical-petrographical and geochemical characteristics. There is a good zonation in the field that …


Late Diagnosed Fanconi's Anemia Presenting Asacute Renal Failure, Hilal Mocan, M. Ziya Mocan, Alisan Yildiran Jan 1998

Late Diagnosed Fanconi's Anemia Presenting Asacute Renal Failure, Hilal Mocan, M. Ziya Mocan, Alisan Yildiran

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Physics

No abstract provided.