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Measurement Of The Diffractive Cross Section In Deep Inelastic Scattering Using Zeus 1994 Data, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti Jan 1999

Measurement Of The Diffractive Cross Section In Deep Inelastic Scattering Using Zeus 1994 Data, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The DIS diffractive cross section, dσdiffγ*p→XN/dMx, has been measured in the mass range Mx < 15 GeV for γ*p c.m. energies 60 < W < 200 GeV and photon virtualities Q2 = 7 to 140 GeV2. For fixed Q2 and Mx, the diffractive cross section rises rapidly with W, dσdiffγ*p→X N (Mx, W, Q2)/dMx ∝ Wadiff with adiff = 0.507 ± 0.034 (stat) +0.155-0.046 (syst) corresponding to a t-averaged pomeron trajectory of ̄αℙ = 1.127 ± 0.009 (stat) +0.039-0.012 (syst) which is larger than ̄αℙ observed in hadron-hadron scattering. The W dependence of the diffractive cross section is found to be the same as that of the total cross section for scattering of virtual photons on protons. The data are consistent with the assumption that the diffractive structure function FD(3)2 factorizes according to cursive greek chiℙFD(3)2(cursive greek chiℙ, β, Q2) = (cursive greek chi0//cursive greek chiℙ)nFD(2)2(β, Q2). They are also consistent with QCD based models which incorporate factorization breaking. The rise of cursive greek chiℙFD(3)2 with decreasing cursive greek chiℙ and the weak dependence of FD(2)2 on Q2 suggest a substantial contribution from partonic interactions.

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Zeus Results On The Measurement And Phenomenology Of F2 At Low Cursive Greek Chi And Low Q2, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti Jan 1999

Zeus Results On The Measurement And Phenomenology Of F2 At Low Cursive Greek Chi And Low Q2, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti

Faculty Publications

Measurements of the proton structure function F2 for 0.6 < Q2 < 17 GeV2 and 1.2 × 10-5 < cursive Greek chi < 1.9 × 10 -3 from ZEUS 1995 shifted vertex data are presented. From ZEUS F2 data the slopes dF2/d ln Q2 at fixed cursive Greek chi and din F2/d ln(1/cursive Greek chi) for cursive Greek chi < 0.01 at fixed Q2 are derived. For the latter, E665 data are also used. The transition region in Q2 is explored using the simplest non-perturbative models and NLO QCD. The data at very low Q2 ≤ 0.65 GeV2 are described successfully by a combination of generalised vector meson dominance and Regge theory. From a NLO QCD fit to ZEUS data the gluon density in the proton is extracted in the range 3 × 10-5 < cursive Greek chi < 0.7. Data from NMC and BCDMS constrain the fit at large cursive Greek chi. Assuming the NLO QCD description to be valid down to Q2 ∼ 1 GeV2, it is found that the qq̄ sea distribution is still rising at small cursive Greek chi and the lowest Q2 values whereas the gluon distribution is strongly suppressed.

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Measurement Of High-Q2 Neutral-Current E+P Deep Inelastic Scattering Cross-Sections At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti Jan 1999

Measurement Of High-Q2 Neutral-Current E+P Deep Inelastic Scattering Cross-Sections At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The e+p neutral-current deep inelastic scattering differential cross-sections dσ/dQ2, for Q2 > 400 GeV2, dσ/dx and dσ/dy, for Q2 > 400, 2500 and 10000 GeV2, have been measured with the ZEUS detector at HERA. The data sample of 47.7 pb-1 was collected at a center-of-mass energy of 300 GeV. The cross-section, dσ/dQ2, falls by six orders of magnitude between Q2 = 400 and 40000 GeV2. The predictions of the Standard Model are in very good agreement with the data. Complementing the observations of time-like Z° contributions to fermion-antifermion annihilation, the data provide direct evidence for the presence of Z° exchange in the …

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Measurement Of Multiplicity And Momentum Spectra In The Current And Target Regions Of The Breit Frame In Deep Inelastic Scattering At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi Jan 1999

Measurement Of Multiplicity And Momentum Spectra In The Current And Target Regions Of The Breit Frame In Deep Inelastic Scattering At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi

Faculty Publications

Charged particle production in neutral current deep inelastic scattering (DIS) has been studied using the ZEUS detector. The evolution of the mean multiplicities, scaled momenta and transverse momenta in Q2 and cursive Greek chi for 10 < Q2 < 5120 GeV2 and cursive Greek chi > 6 × 10-4 has been investigated in the current and target fragmentation regions of the Breit frame. Distributions in the target region, using HERA data for the first time, are compared to distributions in the current region. Predictions based on MLLA and LPHD are inconsistent with the data.

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Critical Adsorption Near Edges, Andreas Hanke, M. Krech, F. Schlesener, S. Dietrich Jan 1999

Critical Adsorption Near Edges, Andreas Hanke, M. Krech, F. Schlesener, S. Dietrich

Physics & Astronomy Faculty Publications

Symmetry breaking surface fields give rise to nontrivial and long-ranged order parameter profiles for critical systems such as fluids, alloys, or magnets confined to wedges. We discuss the properties of the corresponding universal scaling functions of the order parameter profile and the two-point correlation function, and determine the critical exponents η∥ and η⊥ for the so-called normal transition.

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Measurement Of Jet Shapes In High-Q2 Deep Inelastic Scattering At Hera, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti Jan 1999

Measurement Of Jet Shapes In High-Q2 Deep Inelastic Scattering At Hera, J. Breitweg, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, R. Yoshida, H. Zhang, Margarita C. K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The shapes of jets with transverse energies, EjetT, up to 45 GeV produced in neutral- and charged-current deep inelastic e+p scattering (DIS) at Q2 > 100 GeV2 have been measured with the ZEUS detector at HERA. Jets are identified using a cone algorithm in the η-φ plane with a cone radius of one unit. The jets become narrower as EjetT increases. The jet shapes in neutral- and charged-current DIS are found to be very similar. The jets in neutral-current DIS are narrower than those in resolved processes in photoproduction and closer to those in direct-photon processes for the same ranges in …

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A New Formalism For Nonextensive Physical Systems: Tsallis Thermostatistics, Uğur Tirnakli, Fevzi Büyükkiliç, Doğan Demi̇rhan Jan 1999

A New Formalism For Nonextensive Physical Systems: Tsallis Thermostatistics, Uğur Tirnakli, Fevzi Büyükkiliç, Doğan Demi̇rhan

Turkish Journal of Physics

Although Boltzmann-Gibbs (BG) statistics provides a suitable tool which enables us to handle a large number of physical systems satisfactorily, it has some basic restrictions : (i) the range of the microscopic interactions must be small compared to the linear size of the macroscopic systems (short-range interactions) , (ii) the time range of the microscopic memory must be small compared to the observation time (Marcovian processes) and (iii) the system must evolve in an Euclidean-like space-time. In the case of a breakdown in one and/or the others of these restrictions, BG statistics fails. More precisely, the situation could be classified …

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Statistical Physics, Neural Networks, Brain Studies, Gerard Toulouse Jan 1999

Statistical Physics, Neural Networks, Brain Studies, Gerard Toulouse

Turkish Journal of Physics

An overview of some aspects of a vast domain, located at the crossroads of physics, biology and computer science is presented: 1) During the last fifteen years, physicists advancing along various pathways have come into contact with biology (computational neurosciences) and engineering (formal neural nets). 2) This move may actually be viewed as one component in a larger picture. A prominent trend of recent years, observable over many countries, has been the establishment of interdisciplinary centers devoted to the study of: cognitive sciences; natural and artificial intelligence; brain, mind and behaviour; perception and action; learning and memory; robotics; man-machine communication, …

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Spectral Broadening Functions, Slavek Rucinski Jan 1999

Spectral Broadening Functions, Slavek Rucinski

Turkish Journal of Physics

Many astrophysical phenomena involving velocity fields produce broadening of spectral lines. Frequently, the cross-correlation function (CCF) is used to extract information about this broadening from segments of high resolution spectra. CCF has become the standard tool for handing extraction of radial-velocity and broadening information from high resolution spectra as it permits integration of information which is common to many spectral lines into one function which is easy to calculate, visualize and interpret. However, it can be argued that this is not the best tool for applications such as determinations of metallicities ([Fe/H]), for finding locations of star spots on active …

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Angular Momentum Evolution In Close Late-Type Binaries, Carla Maceroni Jan 1999

Angular Momentum Evolution In Close Late-Type Binaries, Carla Maceroni

Turkish Journal of Physics

Accurate monitoring of the orbital period of late-type close binaries can provide important information on their secular evolution and on the structural changes of their components on very short timescales (i.e. decades). The orbital period turns out to be a powerful tool of investigation: it can be measured to great accuracy even with simple equipments and its change produces an easily detectable cumulative effect over time. This paper focuses on two physical mechanisms that cause orbital periods changes in late type binaries with negligible mass loss from the system: the dynamical evolution due to magnetic braking in tidally locked systems, …

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Photometric Imaging Of Starspots, Techniques And Reliability, Zeki̇ Eker Jan 1999

Photometric Imaging Of Starspots, Techniques And Reliability, Zeki̇ Eker

Turkish Journal of Physics

Historical development of the starspot hypothesis and the unsolved problems associated with it are presented. The "non{uniqueness" attributed to the spot solutions is a major problem which could still discredit current efforts of starspot modeling by photometric or spectroscopic data. The basics of the starspot photometry(direct and inverse photometric problem, and the error analysis of the inverse problem) are presented. Since an analytical formulation exists to compute synthetic light curves from the physical parameters of spots, and recomputing original parameters analytically from the synthetic curves are also possible, the starspot hypothesis is a consistent physical problem. According to the error …

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The Light And Colour Variations Of Mm Her, Günay Taş Jan 1999

The Light And Colour Variations Of Mm Her, Günay Taş

Turkish Journal of Physics

RS CVn type eclipsing binary MM Herculis have been observed using B, V, R filters in 1997 and obtained light and colour curves were examined together with the earlier 12 light and colour curves obtained between 1976 and 1997. It was seen that the system is bluer, while it is fainter. Such finding probably reveals the evolutionary effect of the photospheric bright facular structures surrounding starspots.

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The Structure Of Liquid Alkali Metals Calculated By The Thermodynamic Perturbation Theory, H. Bi̇rtan Kavanoz, İdri̇s Gümüş Jan 1999

The Structure Of Liquid Alkali Metals Calculated By The Thermodynamic Perturbation Theory, H. Bi̇rtan Kavanoz, İdri̇s Gümüş

Turkish Journal of Physics

The structure of a hard sphere fluid has been calculated numerically via the Percus-Yevick (PY) and hypernetted-chain (HNC) closure relations and used as a reference system to calculate the structure of liquid alkali metals under the optimized random-phase approximation (ORPA) using the effective ion-ion pair potential formed by the Heine-Abarenkov (HA), and the empty-core (EC) pseudopotentials. The results are compared with experimental results. The calculations made by the reference system under the HNC closure relation are in better agreement with experimental results than those found under the PY closure relation.

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The Lattice Dynamics Of \Gamma-Iron, Kemal Çolakoğlu, G. Uğur, M. Çakmak, H. M. Tütüncü Jan 1999

The Lattice Dynamics Of \Gamma-Iron, Kemal Çolakoğlu, G. Uğur, M. Çakmak, H. M. Tütüncü

Turkish Journal of Physics

Lattice dynamical calculations are performed on \gamma-iron using the Clark-Gazis-Wallis (CGW) model to represent the ion-ion interactions, and a modified form of the Sharma-Joshi model to include ion-electron interactions. The theory is used to compute the phonon dispersion curves, frequency spectra and the lattice specific heat of \gamma-iron. The obtained results are in good agreement with the experimental findings, and are better than those calculated using the other theories.

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Calibration Of Millimetric Marmara Radio Telescope And Radio Detection Of Ozone Line Over Gebze/Kocaeli In Turkey, Mehmet Emi̇n Özel, I. M. Yusifov, A. O. Allakhverdiev, A. A. Vertiy, G. Bayer, Osman Demi̇rcan, H. Kirbiyik, T. Adigüzel Jan 1999

Calibration Of Millimetric Marmara Radio Telescope And Radio Detection Of Ozone Line Over Gebze/Kocaeli In Turkey, Mehmet Emi̇n Özel, I. M. Yusifov, A. O. Allakhverdiev, A. A. Vertiy, G. Bayer, Osman Demi̇rcan, H. Kirbiyik, T. Adigüzel

Turkish Journal of Physics

A brief description of the calibration procedures for the millimetric Marmara Radio Telescope, MRT-2 is presented. Observations carried out during the spectroscopic calibration work is indicative of daily variations of Ozone line of sight density over the telescope location. This being also the first radio observations carried out in Turkey, a short account of observations and results are given.

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Exchange-Correlation Effects In The Impurity-Limited Mobility Of Gaas Quantum Wires, B. Tanatar Jan 1999

Exchange-Correlation Effects In The Impurity-Limited Mobility Of Gaas Quantum Wires, B. Tanatar

Turkish Journal of Physics

We study the many-body effects described by the local-field corrections on the mobility of quasi-one dimensional electron systems. The low temperature mobility due to remote-impurity doping and interface-roughness scattering is calculated within the relaxation time approximation. We find that correlation effects significantly reduce the mobility at low density.

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Semiconductor And Dielectric Microcavity Spectroscopy, Ali̇ Serpengüzel Jan 1999

Semiconductor And Dielectric Microcavity Spectroscopy, Ali̇ Serpengüzel

Turkish Journal of Physics

Semiconductor and dielectric microcavities are used for the localization of photons as well as the enhancement of photon density of states. The enhancement of photoluminescence, electroluminescence, and lasing by the use of microcavities leads to novel active and passive optoelectronic and photonic devices such as channel droppping filters, semiconductor lasers, and resonant cavity enhanced devices. Experimental results showing photoluminescence enhancement in active planar, lasing in active ellipsoidal microcavities as well as light scattering in passive and spherical microcavities are presented.

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Wigner Crystalization In Semiconductor Quantum Wires, I. Al-Hayek, B. Tanatar, M. Tomak Jan 1999

Wigner Crystalization In Semiconductor Quantum Wires, I. Al-Hayek, B. Tanatar, M. Tomak

Turkish Journal of Physics

We study the Wigner crystallization in semiconductor quantum wires within the density functional approach. As the density of electrons in quasi-one-dimensional structures is lowered, we find that the system favors the crystalline phase as envisioned by Wigner.

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Multitime Generalization Of Maxwell Electrodynamics And Gravity, Vladilen Barashenkov Jan 1999

Multitime Generalization Of Maxwell Electrodynamics And Gravity, Vladilen Barashenkov

Turkish Journal of Physics

System of equations of motion for interacting electromagnetic field and charged bodies is derived by means of an action principle in six-dimensional space with a three-dimensional time vector. The influence of the additional (hidden) components of time on the body motion is considered. Macroscopic experiments and astrophysical observations which can reveal the time multi-dimensionality are discussed. At present there are no facts which would be in contradiction with the hypothesis of the multi-dimensionality of time.

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Quantum Mechanics Of The Electric Charge, Andrzej Staruszkiewicz Jan 1999

Quantum Mechanics Of The Electric Charge, Andrzej Staruszkiewicz

Turkish Journal of Physics

The Author summarizes the evidence that his quantum theory of the electric charge depends in a nontrivial way on the numerical value of the fine structure constant.

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Bands Of Localized Electromagnetic Waves In Random Collections Of Dielectric Particles, Marian Rusek, Arkadiusz Orlowski Jan 1999

Bands Of Localized Electromagnetic Waves In Random Collections Of Dielectric Particles, Marian Rusek, Arkadiusz Orlowski

Turkish Journal of Physics

Anderson localization of electromagnetic waves in random arrays of dielectric cylinders is studied. An effective theoretical approach based on the finite size scaling analysis of transmission is developed. The disordered dielectric medium is modeled by a system of randomly distributed 2D electric dipoles. The appearance of the band of localized waves emerging in the limit of an infinite medium is discovered. It suggests deeper insight into existing experimental and theoretical results.

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Electromagnetic Waves In Disordered Dielectric Media: Coupled-Dipole Model, Arkadiusz Orlowski, Marian Rusek Jan 1999

Electromagnetic Waves In Disordered Dielectric Media: Coupled-Dipole Model, Arkadiusz Orlowski, Marian Rusek

Turkish Journal of Physics

An effective approach to multiple scattering of electromagnetic waves by disordered dielectric media is developed. A self-consistent energy-conserving coupled-dipole model is used. Applications to the Anderson localization of electromagnetic waves are presented. A complete set of Maxwell's equations is used to describe the propagation of waves and the vector character of the electromagnetic field is fully taken into account.

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The Wigner Problem In Electrodynamics, Andrzej Horzela Jan 1999

The Wigner Problem In Electrodynamics, Andrzej Horzela

Turkish Journal of Physics

The relation between canonical commutation rules and a shape of acting force is analysed. It is shown that canonical commutation relations and Newtonian equations of motion for a single particle dynamics do imply the force to be of the Lorentz type but the inverse is not true. The example of a single particle motion in a constant magnetic field shows that equations of motion allow an alternative to canonical commutation relations to exist and it is a Lie algebra. The algebra found is of the type of algebras found in studies leading towards noncommutative geometry approaches to physical problems.

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The Gauge Freedoms Of Enlarged Helmholtz Theorem And Debye Potentials; Their Use In The Multipole Expansion Of Conserved Current, Elena N. Bukina, Vladimir M. Dubovik Jan 1999

The Gauge Freedoms Of Enlarged Helmholtz Theorem And Debye Potentials; Their Use In The Multipole Expansion Of Conserved Current, Elena N. Bukina, Vladimir M. Dubovik

Turkish Journal of Physics

We discuss gauge freedom within the scope of the enlarged Helmholtz theorem and Neumann-Debye decomposition and then demonstrate its realization for the multipole expansion of a conserved electromagnetic current. The exact solution to the latter problem was obtained in 1974, but answers to some purely mathematical questions raised by I.B. French and Y. Shimamoto [1] about 40 years ago are given in this paper for the first time.

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Relative L X-Ray Fluorescene Cross-Sections In Heavy Elements In The Energy Region Of 16-122 Kev, Oğuz Doğan, Mehmet Ertuğrul, Önder Şi̇mşek, Ümi̇t Turgut, Hasan Erdoğan Jan 1999

Relative L X-Ray Fluorescene Cross-Sections In Heavy Elements In The Energy Region Of 16-122 Kev, Oğuz Doğan, Mehmet Ertuğrul, Önder Şi̇mşek, Ümi̇t Turgut, Hasan Erdoğan

Turkish Journal of Physics

Relative L1, L\alpha, L\beta and L\gamma x-ray fluorescence cross-sections were observed in Ta, W, Re, Au, Hg, T1, Pb, Bi, Th and U of 16.03, 17.78, 22.58, 25.77, 32.89, 38.18, 43.94, 50.21, 59,5 and 122 keV energies. In this study, L X-ray fluorescence cross-sections were measured at 59.5 and 122 keV and measured values of the other energies were taken from tables by Mann et. al. (1). The experimental relative fluorescene cross-sections were computed for the excitation energies 16.03, 17.78, 22.58, 25.77, 32.89, 38.18, 43.94, 50.21, 59.5 and 122 keV, compared with the theoretically calculated values by Scofield(11). The experimental …

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Supersymmetric Electroweak Radiative Corrections To E^+ E^- -> W^+W^-, S. Alam Jan 1999

Supersymmetric Electroweak Radiative Corrections To E^+ E^- -> W^+W^-, S. Alam

Turkish Journal of Physics

In this short note we summarize some of the work of our thesis, which is also reported elsewhere in detail. We have examined the one loop quantum corrections to the W pair production in the electron positron annihilation in the context of supersymmetric electroweak theory. We have adopted the On Mass Shell Renormalization scheme of Sakakibara and previously demonstrated the consistency of this scheme. The relevant analytic results are written out. A complete computer program for these corrections has been developed. This program has been checked in several ways to ensure against errors over the life of the calculation where …

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Effect Of Illumination Temperature On Thermally Stimulated Current Spectrum Of Tlins_2, Selahatti̇n Özdemi̇r, Rauf Süleymanov, Mahmut Bucurgat, Enver Bulur Jan 1999

Effect Of Illumination Temperature On Thermally Stimulated Current Spectrum Of Tlins_2, Selahatti̇n Özdemi̇r, Rauf Süleymanov, Mahmut Bucurgat, Enver Bulur

Turkish Journal of Physics

The effect of pre-illumination on both thermally stimulated current and photocurrent spectra of TlInS_2 crystal is investigated. The increase in the photosensitivity of the crystal by several orders of magnitude together with the appearance of a new peak in the thermally stimulated current spectrum are observed as a result of the pre-illumination process. The filling of the traps, especially the sensitizing centers, during the pre-illumination is found to be the most favourable physical mechanism to explain the results.

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Implications Of \Delta\Rho And Charm Ii Data For Z' Physics, Durmuş Ali̇ Demi̇r Jan 1999

Implications Of \Delta\Rho And Charm Ii Data For Z' Physics, Durmuş Ali̇ Demi̇r

Turkish Journal of Physics

We discuss the constraints on the Z^{\prime} model parameters coming from Z-pole and low-energy \nu_{\mu}-e scattering data in the frame work of GUT-motivated models. We find that when the coupling constant of the extra U(1) is small (large) the parameter space is mainly determined by the Z-pole (the low-energy \nu_{\mu}-e scattering) data.

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Electroweak Symmetry Breaking In Low-Scale Quantum Gravity, M. Boz, A. Demi̇r, Namik Kemal Pak Jan 1999

Electroweak Symmetry Breaking In Low-Scale Quantum Gravity, M. Boz, A. Demi̇r, Namik Kemal Pak

Turkish Journal of Physics

We discuss the implications of low-scale quantum gravity on electroweak symmetry breaking by computing one-loop gravitational corrections to the Higgs potential. We conclude that these radiative corrections are quite large after summing over the graviton and dilaton Kaluza-Klein towers, and there is no possibility of electroweak symmetry breaking unless one allows for the complex vacuum expectation value for the Higgs field.

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Stellar Observations Made At The Malatya Danjon Astrolabe Station, Orhan Gölbaşi, Hüseyi̇n Kiliç, Fernand Chollet Jan 1999

Stellar Observations Made At The Malatya Danjon Astrolabe Station, Orhan Gölbaşi, Hüseyi̇n Kiliç, Fernand Chollet

Turkish Journal of Physics

We give here the first results of astrometric stellar observations made at the Malatya Station with the modified astrolabe of Paris observatory. This campaign is conducted as part of a cooperation between Inönü University and the Paris Observatory. The astrolabe, which is strictly similar to that of Santiago de Chile, can use two reflecting prisms instead of the trnsparent prism of the Danjon Astrolabe. Consequently, it is possible to observe at the two zenith distances of 30° and 60°. The time is supplied by a GPS receiver which gives UTC with the necessary precision. As the station is a new …

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