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Full-Text Articles in Physical Sciences and Mathematics

On The Nilpotency Class Of Lie Rings With Fixed-Point-Free Automorphisms, Pavel Shumyatsky Jan 2005

On The Nilpotency Class Of Lie Rings With Fixed-Point-Free Automorphisms, Pavel Shumyatsky

Turkish Journal of Mathematics

Let L be a solvable Lie ring with derived length s. Assume that L admits an automorphism \phi of prime order p\geq 11 such that C_L(\phi)=0. It is proved that the class of L is less than \frac{(p-2)^{s+1}}{(p-3)^2}.


Su(2) Representations Of The Groups Of Integer Tangles, Tangül Uygur Jan 2005

Su(2) Representations Of The Groups Of Integer Tangles, Tangül Uygur

Turkish Journal of Mathematics

In this work we classify the irreducible SU(2) representations of \Pi_1(S^3\backslash k_n) where k_n is an integer n tangle and as a result we have proved the following theorem: Let n be an odd integer then \mathcal{R}^{\ast}(\Pi_1(S^3 \backslash k_n)) /SO(3) is the disjoint union of n open arcs where \mathcal{R}^{\ast}(\Pi _1(S^3 \backslash k_n)) is the space of irreducible representations.


Weighted Boundedness For A Rough Homogeneous Singular Integral, Hussain Al-Qassem Jan 2005

Weighted Boundedness For A Rough Homogeneous Singular Integral, Hussain Al-Qassem

Turkish Journal of Mathematics

A weighted norm inequality for a homogeneous singular integral with a kernel belonging to a certain block space is proved. Also, some applications of this inequality are obtained. Our results are essential improvements as well as extensions of some known results on the weighted boundedness of singular integrals.


Alpine Metamorphism And Granitoid Magmatism In The Strandja Zone: New Data From The Sakar Unit, Se Bulgaria, Ianko Gerdjikov Jan 2005

Alpine Metamorphism And Granitoid Magmatism In The Strandja Zone: New Data From The Sakar Unit, Se Bulgaria, Ianko Gerdjikov

Turkish Journal of Earth Sciences

The Strandja Zone is a pre-Cenomanian orogen consisting of three tectonic units: the Veleka, Strandja and Sakar units. The first two units display very low-grade Alpine metamorphism, whereas in the Sakar unit the Triassic sediments are metamorphosed to the amphibolite facies. For years this high-grade metamorphism was enigmatic and most of the metamorphic rocks were interpreted as a reworked Precambrian crust of the Rhodope. This contribution begins with a review of the recent data about the structure and evolution of the Sakar unit. Probably the most important recent finding was the demonstration of the lack of a structural break between …


Trilobites From The Çal Tepe Formation (Cambrian), Near Seydişehir, Central Taurides, Southwestern Turkey, William T. Dean Jan 2005

Trilobites From The Çal Tepe Formation (Cambrian), Near Seydişehir, Central Taurides, Southwestern Turkey, William T. Dean

Turkish Journal of Earth Sciences

The type section of the Çal Tepe Formation, near Seydişehir, is reviewed. The basal dolomite member is unfossiliferous, but the succeeding black limestone member (24 m), light-grey limestone member (10.15 m), and red nodular limestone member (46.7 m) are subdivided into thirty-seven numbered, often fossiliferous beds. Trilobites from the black limestone member, late Early Cambrian, exhibit affinities with Morocco, Spain and northwestern Europe; they include one new genus and species (Pamphyliaspis nigra) and three other new species (Condylopyge matutina, Alueva venulosa, Antatlasia scabra). The lower light-grey limestone member contains Acadoparadoxides (Acadoparadoxides) mureroensis, basal Middle Cambrian index species in Spain, with …


Karst In Turkish Thrace: Compatibility Between Geological History And Karst Type, Mehmet Ekmekçi̇ Jan 2005

Karst In Turkish Thrace: Compatibility Between Geological History And Karst Type, Mehmet Ekmekçi̇

Turkish Journal of Earth Sciences

Geographically, Thrace is a region located in southeastern Europe within the territories of Greece, Bulgaria and Turkey. In Turkish Thrace, karst occurs extensively in Eocene limestones, although some limited karst occurs in marble of the metamorphic series of Palaeozoic age. The karstification base is shallow to very shallow and most of the dolines and poljes have been captured by surface streams. Subsurface drainage has been changed to surface drainage in most parts of the region. Caves and cave relicts are concentrated mainly at three different altitudes, and almost all caves are horizontal or sub-horizontal. With these characteristics, Turkish Thrace hosts …


Shape And Size Characteristics Of Bedload Transported During Winter Storm Events In The Cwm Treweryn Stream, Brecon Beacons, South Wales, Tuncer Demi̇r, R. P. D. Walsh Jan 2005

Shape And Size Characteristics Of Bedload Transported During Winter Storm Events In The Cwm Treweryn Stream, Brecon Beacons, South Wales, Tuncer Demi̇r, R. P. D. Walsh

Turkish Journal of Earth Sciences

Bedload transport in the Cwm Treweryn stream, a tributary of the Usk in the Brecon Beacons, South Wales, was investigated during a wet winter period in early 1995 using basket-type bedload traps and the tracing of painted clasts. The Cwm Treweryn is a typical mountain stream of the region with its gravel-bedload, flashy regime, high gradient and pool-riffle sequences. In particular, the study explored - for a range of categories of clast size - the nature of any influence of clast shape on bedload movement. Competent flows ranging from 2.5 to 19.5 m^3 s^{-1} (the latter close to bankfull flow) …


Laboratory Determination Of Multicomponent Effective Diffusion Coefficients For Heavy Metals In A Compacted Clay, M. Zeki̇ Çamur, Hasan Yazicigi̇l Jan 2005

Laboratory Determination Of Multicomponent Effective Diffusion Coefficients For Heavy Metals In A Compacted Clay, M. Zeki̇ Çamur, Hasan Yazicigi̇l

Turkish Journal of Earth Sciences

Diffusion and sorption of heavy-metal ions (Cd, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn) through an Ankara clay liner were studied experimentally. The Ankara clay consists of calcite, quartz, smectite and illite, and is a highly plastic inorganic clay with optimum weight water content of 32% and corresponding dry density of 1.413 g/cm3. Under optimum compaction conditions, effective porosity (volumetric water content) and hydraulic conductivity in the material were determined as 0.45 and 1.3 to 2.6x10-9 cm/s, respectively. The Ankara clay adsorbed Cd, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn metals, but desorbed Ca, Mg and …


A Solution To Symmetric Teleparallel Gravity, Muzaffer Adak, Özcan Sert Jan 2005

A Solution To Symmetric Teleparallel Gravity, Muzaffer Adak, Özcan Sert

Turkish Journal of Physics

Teleparallel gravity models, in which the curvature and the nonmetricity of spacetime are both set zero, are widely studied in the literature. We work a different teleparallel theory, in which the curvature and the torsion of spacetime are both constrained to zero, but the nonmetricity is nonzero. After reformulating the general relativity in this spacetime we find a solution and investigate its singularity structure.


Investigation Of The Intergrain Junctions Of Polycrystalline Htsc In Rotating Weak Ac Magnetic Fields, Ioseb R. Metskhvarishvili, Magda R. Metskhvarishvili, Luiza Khorbaladze, Mikheil Elizbarashvili, Zaur Miminoshvili, Larisa Nekrasova Jan 2005

Investigation Of The Intergrain Junctions Of Polycrystalline Htsc In Rotating Weak Ac Magnetic Fields, Ioseb R. Metskhvarishvili, Magda R. Metskhvarishvili, Luiza Khorbaladze, Mikheil Elizbarashvili, Zaur Miminoshvili, Larisa Nekrasova

Turkish Journal of Physics

YBa_2Cu_3O_y polycrystalline superconductor has been studied in weak rotating ac magnetic fields with existence of constant dc field. Measurements were carried out in various temperature intervals, and in various variable and constant fields. Results of our experiments are in good agreement with the isotropic model.


Determination Of Defect Distribution In A Ga-Rich Zno/Cds/Cu(In,Ga)Se_2 Solar Cell By Admittance Spectroscopy, Habi̇be Bayhan Jan 2005

Determination Of Defect Distribution In A Ga-Rich Zno/Cds/Cu(In,Ga)Se_2 Solar Cell By Admittance Spectroscopy, Habi̇be Bayhan

Turkish Journal of Physics

This article presents a study on the energy distribution of defects in efficient thin film ZnO/CdS/Cu(In,Ga)Se_2 heterojunction solar cell by the use of admittance spectroscopy. The capacitance spectra of the device has been analyzed using a model based on the existence of a homogeneous distribution of bulk acceptors in the absorber Cu(In,Ga)Se_2 layer. This model reveals an emission from a distribution of hole traps centered at an activation energy of about 300 meV with a defect density of 1.2 \times 10^{17} eV^{-1} cm^{-3}. The band gap of the absorber layer is estimated to be about 1.46 eV which corresponds to …


Magnetic Behaviour Of ``Lithiated'' Fe_2tio_5, M. A. Madare, S. V. Salvi Jan 2005

Magnetic Behaviour Of ``Lithiated'' Fe_2tio_5, M. A. Madare, S. V. Salvi

Turkish Journal of Physics

Fe_2TiO_5 shows a spin glass transition at 53 K and is mainly known for its semiconducting nature. A `LiAl' pair is incorporated in Fe_2TiO_5 by high temperature solid-state reaction. Fe_2TiO_5 + xLiAlH_4 \frac{1000 °C}{24 hrs in atmosphere} \to Fe_2Ti_{1-x} (LiAl)_xO_5 x < x The presence and quantity of ``LiAl'' is confirmed by Inductively Coupled Argon Plasma (IACP) technique. The crystalline geometry is determined by X- ray diffraction and Fourier Transform Infrared (FTIR) spectroscopy of powders. It remains orthorhombic pseudobrookite. Certain reflections of Fe_2TiO_5 are observed to enhance progressively with the content of ``LiAl''. The magnetic hysteresis parameters are observed to depend on the content of ``LiAl''. Initial susceptibility and permeability are measured as a function of temperature. The magnetic order is discussed and explained. It is concluded that the pseudobrookite possesses a `spinel like network', which is strengthened by incorporation of ``LiAl''. It produces a weak long-range ferrimagnetic order in place of short-range antiferromagnetic order. Possible applications are discussed in the text.


New Phases Of Ybacugeo Superconductors Identified From X-Ray Diffraction And Infra-Red Absorption Measurements, Ahmed Abo-Arais, Mohamad Ahmad Taher Dawoud Jan 2005

New Phases Of Ybacugeo Superconductors Identified From X-Ray Diffraction And Infra-Red Absorption Measurements, Ahmed Abo-Arais, Mohamad Ahmad Taher Dawoud

Turkish Journal of Physics

X-ray powder diffraction patterns and infra-red absorption spectra have been evaluated and analysed for the Y_1 Ba_2 Cu_3 O_{7-\delta} - Ge_x compound samples prepared by the solid state reaction with x values ranging from 0.0 to 1.13. All samples show bulk superconductivity above liquid nitrogen temperature using the levitation test (Meissner effect). Samples with Ge content up to x = 0.2 have offset T_c between 83K and 92K while the sample with x = 1.13 shows semiconducting behavior above 100K. As a result of the solid state interaction between YBCO and Ge, new phases are observed and determined, mainly three …


Design And Preparation Of Antireflection Films On Glass Substrate, Muhammad Hammad Asghar, Muhammad Bilal Khan, Shahzad Naseem, Zubair Ahmad Khan Jan 2005

Design And Preparation Of Antireflection Films On Glass Substrate, Muhammad Hammad Asghar, Muhammad Bilal Khan, Shahzad Naseem, Zubair Ahmad Khan

Turkish Journal of Physics

Antireflection coatings (ARC) have been modeled and prepared experimentally for optical and electro-optical applications in the visible spectrum (0.4--0.7 \mu m) to reduce reflections from the surface of glass. Reflection of BK7 bare glass substrate varies from 3.5 to 6.0% over the desired spectrum. This value is reduced reasonably by integrating multilayer thin films, based on dielectric materials, behaving as ARC. Three different three-layer configurations are deposited on glass substrate. The reflection profiles of theoretical and experimental curves are compared and analyzed to demonstrate the use of these multilayered structures. The physical parameters and deposition conditions of the three configurations …


Cosmic Ray Diurnal Anisotropy Related To Solar Activity, Rajesh K. Mishra, Rekha Agarwal Mishra Jan 2005

Cosmic Ray Diurnal Anisotropy Related To Solar Activity, Rajesh K. Mishra, Rekha Agarwal Mishra

Turkish Journal of Physics

The occurrence of a large number high amplitude event (HAE) of cosmic ray diurnal anisotropy during 1981--1994 has been examined as a function of solar activity. The high amplitude days with the time of maximum in the corotational/azimuthal direction do not indicate any significant correlation with solar activity. Our observations suggest that the direction of the anisotropy of HAE events contribute significantly to the long-term behaviour of the diurnal anisotropy. The occurrence of HAE is dominant during sunspot maximum as well as sunspot minimum.


Modeling Global Solar Radiation For A Tropical Location: Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk Jan 2005

Modeling Global Solar Radiation For A Tropical Location: Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk

Turkish Journal of Physics

Monthly average daily values of clearness index and relative sunshine over a period of sixteen years, using quadratic form of the Angstrom-Prescott model have been developed to estimate global solar radiation at Onne (Lat. 4° 46' N, Long. 7° 10' E), a tropical location. The predictive efficiencies of the models are also compared with those developed for the Nigerian environment, and those which are believed to be applicable globally. The applicability of the developed equations was tested in terms of mean percentage error (MPE), mean bias error (MBE) and root mean square error (RMSE).


A Study On Breit Interaction Through Heavy Mesons Spectra, L. I. Abou-Salem, M. S. M. Nour El-Din, M. M. Moussa Jan 2005

A Study On Breit Interaction Through Heavy Mesons Spectra, L. I. Abou-Salem, M. S. M. Nour El-Din, M. M. Moussa

Turkish Journal of Physics

In the present work the adequacy of the complete Breit interaction terms in describing the strong interaction can be tested through studying c\bar{c} and b\bar{b} spectra. Breit equation is solved using the complete Breit interaction form. The Breit equation can be transformed into three categories of differential equations according to the spectroscopic signature of the different states. The resonance masses of c\bar{c} and b\bar{b} states are calculated to order \alpha^4. One can see a good agreement between our results and the corresponding experimental data in all considered states.


Study Of Pseudorapidity Distributions Of Shower Particles Emitted In Interactions Of Nuclei With Emulsion At 4.1- 4.5 A Gev/C, Sakina Fakhraddin Jan 2005

Study Of Pseudorapidity Distributions Of Shower Particles Emitted In Interactions Of Nuclei With Emulsion At 4.1- 4.5 A Gev/C, Sakina Fakhraddin

Turkish Journal of Physics

The pseudorapidity distributions of shower particles in interactions of 4.5 A GeV/c ^{12}C, ^{16}O, ^{28}Si and ^{22}Ne at 4.1 A GeV/c with emulsion have been presented. The dependence of these distributions on the target nuclei (AgBr and CNO) have been investigated. The energy density for ^{24}Mg--Pb interactions is calculated using the Bjorken model.


Microstructure Characterization Of Znfe_{2-X}M_{X}O_{4} (M = Bi, Y And X = 0.1, 0.2) Ferrites By The Rietveld Refinement, Mansour Al-Haj Jan 2005

Microstructure Characterization Of Znfe_{2-X}M_{X}O_{4} (M = Bi, Y And X = 0.1, 0.2) Ferrites By The Rietveld Refinement, Mansour Al-Haj

Turkish Journal of Physics

The microstructure of the ferrites was analyzed by the Reitveld refinement method. The Bi-containing ferrites revealed a decrease in the lattice parameter as the Bi^{3+} concentration is increased, due to the distortion of the ferrite lattice. There was a minor distortion in the ZnFe_{1.9}Y_{0.1}O_4 ferrite lattice. A minor yttrium oxide phase coexisted with the ZnFe_{1.8}Y_{0.2}O_4 spinel phase.


Composition Dependence Of Photoconductivity In Amorphous Thin Films Of Se_{.80-X}Te_{.20}Ge_X, Deepak Kumar, Santosh Kumar Jan 2005

Composition Dependence Of Photoconductivity In Amorphous Thin Films Of Se_{.80-X}Te_{.20}Ge_X, Deepak Kumar, Santosh Kumar

Turkish Journal of Physics

The present paper reports the dependence on composition of photoconductivity in vacuum evaporated thin films of amorphous Se_{.80-x}Te_{.20}Ge_x (x = .05, .10, .15 and .20). Temperature dependence of conductivity in dark as well as in presence of light show that conduction is through a thermally activated process in both cases. The activation energy is found to decrease with increase in light intensity, indicating shift of the Fermi level with intensity. A correlation between activation energy and the pre-exponential factor is observed in all the compositions, which could be fitted to the Meyer-Neldel rule. Measurements on the dependence of photoconductivity on …


Low Frequency Dispersion In Non-Conducting Contacts In Humidity, Altaf Husain, S. Shakeel Ahmed Jan 2005

Low Frequency Dispersion In Non-Conducting Contacts In Humidity, Altaf Husain, S. Shakeel Ahmed

Turkish Journal of Physics

To develop an enhanced understanding of an aspect of the charge transport mechanism in systems composed of solid-solid insulating contacts, the dynamic dielectric response of sand grains and of silica-silica rod contacts was investigated at dry and at 97% relative humidity (RH), in the frequency range 10^{-2} to10^5 Hz. In dry atmosphere no appreciable amount of conductivity is observed, while in humidity the response follows a strongly dispersive behaviour. Sharp rise in capacitance gives a clear evidence for the storage of charge in the transport process. Collectively, the conductance of the sand grains increases super-linearly with the number of contacts …


Optical Characterization Of Chemical Bath Deposited Bismuth Oxyiodide (Bioi) Thin Films, F. I. Ezema Jan 2005

Optical Characterization Of Chemical Bath Deposited Bismuth Oxyiodide (Bioi) Thin Films, F. I. Ezema

Turkish Journal of Physics

Thin films of Bismuth oxyiodide (BiOI) were deposited, using chemical bath deposition techniques. The films were characterized using energy dispersive x-ray fluorescence (EDXRF) and Fourier transform infrared (FTIR) spectroscopy for chemical composition, and a spectrophotometer for the analysis of spectral absorbance / transmittance / reflectance. Deposited film thickness ranged between 0.115 and 0.140 \mu m. The optical properties deduced from the spectral absorbance / transmittance / reflectance include the maximum values of the refractive index n that ranged between 2.62 and 2.64, the extinction coefficient k ranged between 25.84 \times 10^{-3} and 42.92 \times 10^{-3} while the Optical conductivity \sigma …


Electrical And Structural Properties Of Ex-Situ Annealed Superconducting Bi_2sr_2cacu_2o_8 Thin Films Obtained By Coevaporation Of Components, Necdet Baştürk Jan 2005

Electrical And Structural Properties Of Ex-Situ Annealed Superconducting Bi_2sr_2cacu_2o_8 Thin Films Obtained By Coevaporation Of Components, Necdet Baştürk

Turkish Journal of Physics

Bi_2Sr_2CaCu_2O_8 system superconducting thin films were obtained by synchronized deposition of Bi, Cu, CaF_2 and SrF_2 components onto cleaved MgO (100) single crystal substrates after annealing in the temperature range 600--840 °C. The films were annealed in H_2O and O_2, then dry O_2 atmosphere for the removal of fluorine from the structure and to attain superconducting properties. X-ray powder diffraction patterns were used to characterize the obtained film structure. The films were observed to grow along c-axis perpendicular to the substrate surface with the identified reflection on the (00l, l = 6, 8, 10...) planes. The films having the critical …


Dielectric Relaxation In Glassy Se_{100 - X} Sb_X, N. Choudhary, A. Kumar Jan 2005

Dielectric Relaxation In Glassy Se_{100 - X} Sb_X, N. Choudhary, A. Kumar

Turkish Journal of Physics

Frequency and temperature dependence of dielectric constant \varepsilon' and dielectric loss \varepsilon'' are studied in glassy Se_{1-x} Sb_x (x = 0, 0.02, 0.04, 0.06, 0.08 and 0.10) in the frequency range from 1--10 kHz and in the temperature range 290 K to 360 K. The experimental results indicate that no dielectric dispersion exist in glassy Se in the operating range of frequencies. However, when Sb concentration increases in Se_{1-x} Sb_x (x = 0.02, 0.04, 0.06, 0.08 and 0.10) dielectric dispersion starts in the upper frequency and temperature range. The values of \varepsilon' and \varepsilon'', as functions of temperature and frequency, …


Electron-Deuteron Tensor Polarization And D-State Probability, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser Jan 2005

Electron-Deuteron Tensor Polarization And D-State Probability, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser

Turkish Journal of Physics

Electron-deuteron tensor polarization T_{21}(q) is calculated for thirty-three N-N local potential models. New relations have been found between the peak value of T_{21}(q) and some of the deuteron properties. An experimental value of deuteron D-state probability P_D = 5.9861\% \pm 0.2687\% is deduced.


Multiple Scale And Hamilton-Jacobi Analysis Of Extended Mathieu Equation, Özlem Yeşi̇ltaş, Mehmet Şi̇mşek Jan 2005

Multiple Scale And Hamilton-Jacobi Analysis Of Extended Mathieu Equation, Özlem Yeşi̇ltaş, Mehmet Şi̇mşek

Turkish Journal of Physics

In this study, we use perturbation approximations and semiclassical methods to investigate the boundary solutions of non-linear vibrating systems. The extended Mathieu Equation, related to the perturbed Van der Pol oscillator with periodic coefficients, is solved using multiple time scales. Then, using the Von Zeipel Method, which is based on the Hamilton-Jacobi theory, stability conditions are presented. It is shown that the stability boundaries are the same with those obtained by both methods.


Quantization Of Reparametrized Systems Using The Wkb Method, Khaled I. Nawafleh, Eqab M. Rabei, Humam B. Ghassib Jan 2005

Quantization Of Reparametrized Systems Using The Wkb Method, Khaled I. Nawafleh, Eqab M. Rabei, Humam B. Ghassib

Turkish Journal of Physics

The quantization of reparametrized systems is discussed using the WKB approximation. The Hamilton-Jacobi function, the equations of motion and the wave function---which the conditions constrain in the semiclassical limit---are determined. The success of this approach is then demonstrated for two applications. The first is an illustrative example of nonrelativistic dynamics. The second is the well-known motion of a relativistic particle in an external electromagnetic field.


Mössbauer, Infrared And X-Ray Studies For Ni_{0.5}Zn_{0.5}Cr_Xfe_{2-X}O_4 Ferrites, Mohamed Amer, S. Ata-Allah, T. Meaz, S. Aboul-Enein, M. Abd-El-Hamid Jan 2005

Mössbauer, Infrared And X-Ray Studies For Ni_{0.5}Zn_{0.5}Cr_Xfe_{2-X}O_4 Ferrites, Mohamed Amer, S. Ata-Allah, T. Meaz, S. Aboul-Enein, M. Abd-El-Hamid

Turkish Journal of Physics

Spinel ferrites of the system Ni_{0.5}Zn_{0.5}Cr_xFe_{2-x}O_4, 0 \le x \le 1, have been studied via Mössbauer, IR and X-ray spectra. Mössbauer spectra of the samples showed broad six-line patterns and a central paramagnetic phase. The spectra have been analyzed to two magnetic patterns, A and B, and two quadrupole doublets, C_A and C_B. The patterns A and C_A are assigned to Fe^{3+} ions at the tetrahedral A-sites and the patterns B and C_B to Fe^{3+} and Fe^{2+} ions at the octahedral B-sites. The deduced hyperfine interaction parameters; the isomer shifts, quadrupole splitting, outermost line widths, hyperfine magnetic fields and bulk …


Influence Of Solar Activity On Low Amplitude Cosmic Ray Diurnal Anisotropy, Rajesh K. Mishra, Rekha Agarwal Mishra Jan 2005

Influence Of Solar Activity On Low Amplitude Cosmic Ray Diurnal Anisotropy, Rajesh K. Mishra, Rekha Agarwal Mishra

Turkish Journal of Physics

A detailed study has been conducted on the occurrence of a large number of low amplitude events (LAE) of cosmic ray (CR) diurnal anisotropy during 1981--1994 as a function of solar activity. The low amplitude days with the time of maximum in the corotational/azimuthal direction do not indicate any significant correlation with solar activity. Our observations suggest that the direction of the anisotropy of LAE events contribute significantly to the long-term behaviour of the CR diurnal anisotropy. The occurrence of LAE is dominant during solar activity minimum years.


East-West And Radial Anisotropy In Cosmic Ray Modulation, Rekha Agarwal Mishra, Rajesh K. Mishra Jan 2005

East-West And Radial Anisotropy In Cosmic Ray Modulation, Rekha Agarwal Mishra, Rajesh K. Mishra

Turkish Journal of Physics

The cosmic ray (CR) data observed with the Deep River neutron monitoring station has been harmonically analyzed for the period 1964--95 to obtain the diurnal and semi-diurnal components of cosmic ray intensity on geomagnetically 60 quiet days. The annual diurnal anisotropy vectors have been resolved into two components: one along the 12-Hr direction, the radial anisotropy component; and the other along 18-Hr direction, east-west anisotropy component. It is observed that when the polarity of solar poloidal magnetic field (SPMF) in northern hemisphere (NH) is positive, the radial anisotropy component increases; whereas, the east-west anisotropy component decreases. This results in shifting …