Cairo University

MTPR Journal

 

THE VARIATION OF THE SOLAR DIAMETER AND IRRADIANCE: ECLIPSE OBSERVATION OF JULY 11, 2010

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0001
SERGE KOUTCHMY, CYRIL BAZIN, JEAN-YVES PRADO, PHILIPPE LAMY and PATRICK ROCHER

The variation of the solar diameter is the subject of hot debates due to the possible effect on the Earth climate and also due to different interpretations of long period solar variabilities, including the total irradiance. We shortly review the topic and show that rather long term variations, corresponding to a length well over a solar magnetic cycle, are interesting to consider. The very recently launched mission “Picard” is entirely devoted to the topic but will just permit a short term evaluation. At the time of the last solar total eclipse of 11/7/2010, several experiments were prepared to precisely measure the transit time of the Moon related to the precise value of the solar diameter. Preliminary results coming from the use of a specially designed CNES photometer, put on different atolls of the French Polynesia, are presented. In addition the results of new experiments devoted to fast observations of flash spectra, including their precise chrono-dating, are illustrated and discussed. A new definition of the edge of the Sun, free of spurious scattered light effects strongly affecting all out of eclipse evaluations, is emerging from these observations, in agreement with the most advanced attempts of modeling the outer layers of the photosphere. We also argue for a definite answer concerning the solar diameter measurement from eclipses based on a better precision of lunar profiles coming from lunar altimetry space experiments which will be possible in the following decades.

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Photo-excitation and Photoionization for Plasma Opacities under the Iron Project

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0002
Sultana N. Nahar

Opacity gives a measure of radiation transport in a medium such that higher or lower opacity indicates more or less attenuation of radiation. As the radiation propagates, opacity is caused by the absorption and emission of radiation by the constituent elements in the medium, such as astrophysical plasmas. It is also affected by photon scatterings. Hence opacity depends mainly on the intrinsic atomic processes, photo-excitation in a bound-bound transition, photoionization in a bound-free transition, and photon-electron scattering. Monochromatic opacity at a particular frequency, κ(ν), is obtained mainly from oscillator strengths (f) and photoionization cross sections (σPI). However, the total monochromatic opacity is obtained from summed contributions of all possible transitions from all ionization stages of all elements in the source. Calculation of accurate parameters for such a large number of transitions has been the main problem for obtaining accurate opacities. The overal mean opacity, such as Rosseland mean opacity (κR), depends also on the physical conditions, such as temperature and density, elemental abundances and equation of state such as local thermodynaic equilibrium (LTE) of the plasmas. For plasmas under HED (high energy density) conditions, fluid dynamics may be considered for shock waves such as in a supernova explosion. In this report, I will exemplify the necessity for high precision atomic calculations for the radiative processes of photoexcitation and photoionization in order to resolve some perplexing astrophysical problems relevant to elemental abundances and hence opacities. In particular I will present results on oscillator strengths of Fe XVIII and photoionization cross sections of Fe XVII which are abundant in high temperature plasmas, such as solar corona, and photoionization and recombination of O II which is abundant in low temperature plasmas, such as in a planetary nebula. Sophisticated atomic calculations under the Iron Project are revealing important and dominant features not included in the current opacities. Opacities with these new results are expected to resolve the longstanding problems on abundances in the sun, orion nebula etc.

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PHYSICS OF THE CORONA AND PRESENT AND FUTURE MAJOR SOLAR AND HELIOSPHERIC SPACE MISSIONS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0003
LUC DAMÉ

Several ground facilities and space missions are currently dedicated to the study of the Sun at high resolution and of the solar corona in particular. However, and despite significant progress with the advent of space missions and UV, EUV and XUV direct observations of the hot chromosphere and million degrees coronal plasma, much is yet to be achieved in the understanding of these high temperatures, fine dissipative structures and of the coronal heating in general. Recent missions, in particular Hinode, have shown the definite role of waves and of the magnetic field deep in the inner corona, at the chromosphere-corona interface, where dramatic changes occur. Observations of multithermal loops and modelling will be presented…

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SOLAR ACTIVITIES AND SPACE WEATHER HAZARDS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0004
AHMED A. HADY

Geomagnetic storms have a good correlation with solar activity and solar radiation variability. Many proton events and geomagnetic storms have occurred during solar cycles21, 22, and 23. The solar activities during the last three cycles, gave us a good indication of the climatic change and its behavior during the 21st century. High energetic eruptive flares were recorded during the decline phase of the last three solar cycles. The appearances of the second peak on the decline phase of solar cycles have been detected. Halloween storms during Nov. 2003 and its effects on the geomagnetic storms have been studied analytically. The data of amplitude and phase of most common indicators of geomagnetic activities during solar cycle 23 have been analyzed.

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ELECTRON BEAM ION TRAP AND ITS APPLICATIONS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0005
YAMING ZOU

Electron Beam Ion Traps (EBIT), initially developed at LLNL, are sophisticated devices capable of acting both as highly charged ion (HCI) light sources and ion sources. As a HCI light source, they can basically provide light from emission states of any charge state of any element in the periodic table, hence almost unique for spectroscopic research. Furthermore, the emitting ions are almost at rest compared to those produced by heavy ion accelerators or storage rings, much less bothered with Doppler shifts and line broadening. Because of its flexibility in producing various ions, it is very good for studies along iso-electronic sequences, and along iso-nuclear charge sequences to reveal physical properties behind experimental phenomenon. In an EBIT, a thin plasma can be formed with basically any elements, and more important with almost mono-energy electrons. On top of this, the electron energy can be tuned in the range of few hundreds eV to above one hundred keV. This property made it possible to use an EBIT for detail studies of processes in hot plasmas, so as to make disentangling studies of hot plasmas and to assist plasma diagnostics for temperature, density, electromagnetic field, as well as ion moving…

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GENERATION, DESIGN AND APPLICATIONS OF HIGH ENERGY ELECTRON BEAM SOURCES - AN OVERVIEW

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0006
MUNAWAR IQBAL, GHALIB UL ISLAM, HARIS RASHID and FAZAL-E-ALEEM

Thermionic electron beam is a fundamental part of linear accelerators in the field of Experimental High Energy Physics (EHEP). Thermionic type of beam is very economical and easy to produce as compared to the other electron beam sources. In this work, we give an overview of generation, design and applications of the electron beam with particular reference to e-beam generation at high energy physics linear accelerators. The data, which is available in the literature is presented in tabular form for ready reference. In order to have a feel of the vast applications of e-beam technology, we elaborate an e-beam source developed in our laboratory.

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FUNDAMENTAL STUDIES AND APPLICATIONS OF HIGHLY CHARGED IONS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0007
REINHOLD SCHUCH

The talk addresses the novel physics that is done with trapped Highly Charged Ions (HCI). We have built up an Electron Beam Ion Trap (SEBIT) at AlbaNova that is now been upgraded to a super-EBIT version for making HCI up to bare uranium ions at rest. Examples are given where this facility together with novel instrumentation is used in challenging new experiments in atomic and fundamental studies:…

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CLASSIFICATION OF SPECTRAL WAVELENGTHS IN ALL REGIONS FOR Si XII

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0008
A. I. REFAIE

Fine structure energy levels, wavelengths, log gf and radiative dipole allowed (E1) transitions have been calculated for lithium-like Si XII. Relativistic Hrtree-Fock and configuration interaction effects have been included in the calculations using the electrostatic parameters that have been optimized by a least squares approach, in order to improve the adjustment to the observed energy levels and transition rates. The 69 fine structure energy levels of total angular momenta, 1/2 ≤ J ≤ 9/2 of even and odd parities, total angular momentum 2 ≤ l ≤ 5 for 2 ≤ n ≤ 10. The spectral wavelengths of 627 lines have been calculated in addition to their radiative transition probabilities. The calculated results obtained from Breit –Pauli show a very good agreement in soft X-ray, EUV and far UV regions with almost all observed and calculated values. In the visible and near IR, the present results are in comparable with the measured and calculated ones. An acceptable discrepancy has been shown in the mid IR region in both measured and calculated results. The comprehensive data sets are applicable for various models such as for ionization balance and recombination-cascade for EUV and X-ray lines.

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SOME HISTORIC AND CURRENT ASPECTS OF PLASMA DIAGNOSTICS USING ATOMIC SPECTROSCOPY

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0009
ROGER HUTTON

The use of atomic spectroscopy in the diagnostics of hot plasma, whether terrestrial or astrophysical, has a long and distinguished history. Some examples of past highlights will be given, along with a mention of their impact on contemporary thinking. In terms of more current lines of research on atomic spectroscopy relevant to plasma diagnostics, we will discuss more subtle effects concerning the influence of magnetic and nuclear interactions on atomic structure. For example, there are more effects of magnetic fields on atomic structure than the often though about Zeeman splitting of atomic energy levels. As magnetic fields exist in many astrophysical plasmas and also in Tokomak machines, this line of research may be of great importance to these very important branches of physics. Similarly, effects of nuclear-spin, through the hyperfine interaction, can have dramatic effects on the lifetimes of forbidden transitions. Again, important additions to plasma diagnostics are expected through effects caused by the hyperfine interaction. We will also stress the importance of Electron Beam Ion Traps as excellent laboratory light sources to study such potentially very interesting effects.

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NOVELTY PREPARATION, CHARACTERIZATION AND ENHANCEMENT OF MAGNETIC PROPERTIES OF MN NANOFERRITES USING SAFETY BINDER (EGG WHITE)

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0010
M. A. AHMED, N. OKASHA and S. I. EL-DEK

Nanocrystalline MnFe2O4 ferrite was prepared using natural binder; egg white was used as an aqueous medium to extend nanoparticle preparation better than any other interesting materials. X-ray diffraction (XRD) and transmission electron microscope (TEM) showed also that the investigated samples revealed the nanosized structure with crystallite size of 39nm. The magnetic susceptibility measurements give a Curie temperature TC = 613K with effective magnetic moment 23 B. M. The values of magnetic constants as obtained from hysteresis data are, saturation magnetization Ms = 13.71 emu/g, remanent magnetization Mr = 0.1694 emu/g and coercivity Hc = 25.6 Oe.

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STARK BROADENING CALCULATIONS OF SEVERAL Ti LINES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0011
A. I. REFAIE and H. SHARKAWY

This work reports calculated Stark broadening transition of several Ti lines at 1064 nm in a laser-produced plasma (ne = 2.27-1.59 × 1019 cm−3). The method is based on the assumption of homogenous plasma and local thermodynamical equilibrium (LTE). Electron temperatures are in the range of 0.79-0.85 eV. There is no data available to be compared with the present calculated parameters except only one experimental reference has been used to compare only three lines with the present data.

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Nanostructure iron-silicon thin film deposition using plasma focus device

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0012
M. Kotb, A. H. Saudy, S. Hassaballa and M. M. ElOker

The presented study in this paper reports the deposition of nano-structure iron-silicon thin film on a glass substrate using 3.3 KJ Mather-type plasma focus device. The iron-silicon powder was put on the top of hollow copper anode electrode. The deposition was done under different experimental conditions such as numbers of electric discharge shots and angular position of substrate. The film samples were exposed to energetic argon ions generated by plasma focus device at different distances from the top of the central electrode. The exposed samples were then analyzed for their structure and optical properties using X-ray diffraction (XRD) and UV-visible spectroscopy. The structure of iron-silicon thin films deposited using plasma focus device depends on the distance from the anode, the number of focus deposition shots and the angular position of the sample

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SIZE CONFINEMENT AND MAGNETIZATION IMPROVEMENT BY LA3+ DOPING IN BIFEO3 QUANTUM DOTS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0013
M. A. AHMED, S. I. El-DEK and M. S. AYOUB

A series of La3+ doped nanoparticles of BiFeO3 multiferroic samples was prepared using solid state reaction. Structural and magnetic properties were investigated using XRD, TEM, magnetic susceptibility and M-H loop. All samples were antiferromagnetic in character. Maximum coercivity HC = 5265 Oe was obtained at x = 0.25. Improvement of the magnetization of BiFeO3 is achieved by La3+ at different doping levels.

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SYNTHESIS OF RARE-EARTH DOPED AND UNDOPED GaN NANO-CRYSTALLITES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0014
LOTFIA EL NADI, SAMAH AHMED, M. AWAAD, MAGDY OMAR and YEHIA BADR

Semiconductor nanostructures doped with rare earth ions is a possible way to overcome the limitation of low luminescence efficiency of rare earth ions, providing that the strong confinement of carriers in dots will enhance their recombination in the vicinity of RE ions. Undoped and Eu3+-doped GaN crystallites have been synthesized by the co-precipitation method followed by nitridation reaction at 1100 °C for 2 h, under a continuous flow of NH3 gas. X-ray diffraction patterns (XRD) revealed that the synthesized undoped and Eu3+-doped GaN crystallites are of a single-phase wurtzite structure. The morphology of the samples was examined by field emission scanning electron microscope (FE-SEM) and high resolution transmission electron microscope (HR-TEM), and it was shown that the micron-sized particles are composed of agglomerated nano-crystallites. Under the above band gap excitation, all samples exhibited room-temperature photoluminescence with the characteristic GaN band-edge emission peak centered at 363 nm (∼3.4 eV, FWHM ∼ 10 nm) as well as broad defect-related emission peak centered at about 405 nm. The Eu-doped GaN sample, under below bandgap excitation, exhibited red emission peaks centered at 593 nm and 616 nm corresponding to the 5D0 → 7F1 and 5D0 → 7F2 transitions, respectively, within the 4f shell of Eu3+ ions.

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THE FORMATION AND CHARACTERIZATION OF NANOCRYSTALLINE MN-FERRITE FROM MAGNETITE

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0015
M. A. AHMED, N. OKASHA and D. NABEEL

Nanocrystalline manganese ferrite of MnxFe3-xO4 with x = 0, 0.2, 0.4 and 0.6 was prepared by chemical co-precipitation method. The as prepared samples were characterized by XRD and magnetization. X-ray diffraction patterns confirmed the inverse spinel structure of ferrites particles with size ranged from 12 to 30 nm. The Magnetic properties such as typical saturation magnetization (Ms), remanence magnetization (Mr) and coercive field (Hc) measured at room temperature along with doped at different Mn contents show that the maximum Mn ions content doped into ferrite lattices is x = 0.4 which agree well with the magnetic susceptibility (χM) measurements and the high magnetic parameters.

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THE STRUCTURAL, SPECTRAL AND DIELECTRIC PROPERTIES OF COMPOSITE SYSTEM NZF-BT

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0016
O. M. HEMEDA, A. TAWFIK, M. A. AMER, B. M. KAMAL and D. E. EL REFAAY

The Composite material of NiZnFe2O4 and BaTiO3 were prepared by double sintering ceramic technique. X-ray diffraction pattern for composite xBaTiO3 + (1-x) Ni0.8Zn0.2 Fe2O4 where (x = 0%, 20%, 40%, 60%, 80% and 100%) show the presence of diphase and confirms the successful preparation the composite. Some parameters were deduced from the analysis of x-ray like porosity, density, particle size and the lattice constant for both phases were calculated from XRD. SEM shows nearly homogeneous microstructure with good dispersion of BT grains and the presence of some pores. There was an enlargement of BT grain by BT content. IR spectra of composite sample indicate that BT content affect the intermolecular character of the ferrite. A rise in dielectric constant occurs at high temperature due to the effect of space change resulting from the increase of change carriers in paramagnetic region. The dielectric loss (tan δ) decrease by increasing BT content.

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ON THE ELECTRICAL CONDUCTIVITY OF POLY(VINYLCHLORIDE)/POLY(ETHYLENE OXIDE) BLENDS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0017
G. M. NASR, S. M. ABD EL-WAHAB and A. ABD EL-ATHEM

Physical blending of different polymers is a very popular, simple and economical method of preparing composite with desirable and useful properties. The electrical conductivity of blends of amorphous poly(vinyl chloride) (PVC) with semicrystalline poly(ethylene oxide) (PEO) in the form of thin films has been measured by studying the I-V characteristics at room temperature and temperature dependence of the sample conductivity. The results are presented in the form of I-V characteristics and analysis has been made by interpretation of Poole Frenkel, Fowler-Nordheim and Schottky-Richardson plots. The analysis of these results suggests that Schottky - Richardson mechanism are primarily responsible for the observed conduction. Meanwhile, the percolation concentration of PEO in PVC matrix was found to be round 10%. Furthermore, the mechanism of electrical transport in this system is examined in temperature range 300-350K. The temperature dependence of conductivity gives evidence for the charge carriers transport mechanism via the occurred agreement of experimental results with the employed hopping models.

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CONDUCTIVITY ENHANCEMENT OF Mn Zn FERRITE BY GAMMA IRRADIATION

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0018
M. A. AHMED, A. M. DIAB and S. F. MANSOUR

A series of the ferrite system Mn1-xZnxFe2O4 (x = 0.0, 0.05, 0.1, 0.15, and 2.0) were prepared by the standard ceramic method. The X-ray diffraction patterns confirmed the formation of single phase cubic structure and shows also that the lattice constant decreases with increasing Zn content. The effect of Zn+2 ion concentration on the structural and the electrical properties of the investigated samples are studied. The most important result of γ-irradiation on the electrical properties is the variation of change ratio Fe2+ Fe3 + e− on the octahedral site leading to an increase in the conductivity as well as the dielectric constant.

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EFFECT OF Y3+ CATION ON ELECTRICAL PROPERTIES OF Ni-Zn FERRITES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0019
L. M. SALAH

Two groups of the ferrite samples of the general formula Ni0.5Zn0.5YyFe2-iyO4; were prepared by double sintering ceramic method. The first group, i=1, 0.02 y 0.12 i.e. the Fe ion was partially substituted the Y ion. The second group; i=0, 0.02 y 0.08 i.e. the Y ion was added to the Ni0.5 Zn0.5Fe2O4. The influence of Y3+ ion on the electrical properties of the two groups of the investigated samples is studied. It is noticed that the ac conductivity (ln) are nearly constant for all Y3+ ion concentration for the two groups. This result confirm the x-ray diffraction data and the calculated values of the cation distribution, where the process of dissolution of any ratio of yttrium in the cubic spinel lattice never occurs but exists outside the grain as aggregation and the non stoichiometeric system can redistribute itself to produce a single phase of cubic spinel under the suitable sintering process. The obtained results indicate that the ac conductivity of the investigated samples is controlled by hopping mechanism. The dielectric constant (ε′) as well as dielectric loss (tanδ) change. The obtained result is discussed in view of Maxwell–Wagner process.

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CHARACTERIZATION AND DRAMATIC VARIATIONS OF THE MAGNETIC PROPERTIES OF Cu-DOPED NANOMETRIC CO-FERRITE

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0020
M. A. AHMED, S. F. MANSOUR and M. A. ABDO

Structure and magnetic properties of Co1-xCuxFe2O4 were investigated. Cobalt ferrite has been synthesized by double sintering ceramic technique. X-ray Diffraction (XRD) analysis and Transmission Electron Microscope (TEM) confirmed the formation of single phase cobalt ferrite nanoparticles in the range 38 − 46 ± 3nm which is a good result for this method of preparation. The magnetic susceptibility was studied at different temperature as a function of magnetic field intensities. The room temperature hysteresis loop was performed for the present samples in the field intensity of 108kOe using VSM. The parameters of X-ray density (dx) and apparent density (da) increases with increasing Cu+2 concentrations in the prepared samples.

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ELECTRONIC STRUCTURE AND MAGNETIC PROPERTIES OF THE ND2FE14B INTERMETALLIC COMPOUND

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0021
ABEER E. ALY

The calculations on electronic structures of Nd2Fe14B are calculated using first-principles full-potential linearized augmented plane wave (FPLAPW) method. We study the magnetic properties of Nd2Fe14B using the LDA+U and spin-orbit coupling methods. Results are presented for total density of states (DOS) as well as the site-projected partial density of states (PDOS) and the spin magnetic moment of Fe at each of the six in-equivalent transition-metal sites. The total spin-magnetic moments and the average Fe moment are in a good agreement with the values deduced from the neutron scattering experiment. The spin-polarized calculations, excluding the Hubbard and SO interaction, resulted in the total spin magnetic moment is 46.6 μB compared to the experimental values 34.63 μB to the value of 39.6 μB we obtained using LDA+U scheme without Spin-Orbit coupling(SO). But using LDA+U +SO the total spin magnetic moment is 37.6 μB.

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THE OPTICAL PROPERTIES OF POLY (VINYL CHLORIDE)/POLY (ETHYLENE OXIDE) BLENDS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0022
G. M. NASR, S. M. ABD EL-WAHAB and A. ABD EL-ATHEM

The miscibility and optical properties of polyvinylchloride (PVC) blends with different concentration of polyethylene oxide (PEO) have been studied. FTIR spectroscopy studies show the presence of interactions between blend constituents. The optical properties in the UV-visible regions are investigated at room temperature. From absorption spectra in UV-visible regions, the dependence of the absorption coefficient on the photon energy suggests the presence of both direct and indirect allowed transitions in k-space. The values of the optical band gap (Eopt) for both transitions have been obtained. The width of the tail of localized states in the band gap (Eu) was evaluated using the Urbach-edges. Both the parameters (Eopt) and (Eu) vary with different PEO content.

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GIANT ENHANCEMENT IN THE PHYSICAL PROPERTIES OF LaFeO3 BY SUBSTITUTION OF DIVALENT IONS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0023
M. A. AHMED, S. I. DEK and M. M. ARMAN

Perovskites with the general formula La1-xMxFeO3, x = 0.0 and x = 0.3, M = Ca2+, Sr2+ and Ba2+ were prepared by the double sintering ceramic technique. The X-ray powder diffraction, IR and TEM were carried out to characterize the samples. The molar magnetic susceptibility (χM) was enhanced by substitution the divalent metal ion (M2+ = Ca2+, Sr2+ and Ba2+) instead of La+3. The saturation magnetization for both Ca2+ and Sr2+ substituted samples is increased up to 10 times its values for the parent which allow to use these samples in many applications. The Ca substitution improves the conductivity by more than 18 times while the Sr enhances it by 25 times.

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GIANT ENHANCEMENT IN THE PHYSICAL PROPERTIES OF LaFeO3 BY SUBSTITUTION OF DIVALENT IONS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0023
M. A. AHMED, S. I. DEK and M. M. ARMAN

Perovskites with the general formula La1-xMxFeO3, x = 0.0 and x = 0.3, M = Ca2+, Sr2+ and Ba2+ were prepared by the double sintering ceramic technique. The X-ray powder diffraction, IR and TEM were carried out to characterize the samples. The molar magnetic susceptibility (χM) was enhanced by substitution the divalent metal ion (M2+ = Ca2+, Sr2+ and Ba2+) instead of La+3. The saturation magnetization for both Ca2+ and Sr2+ substituted samples is increased up to 10 times its values for the parent which allow to use these samples in many applications. The Ca substitution improves the conductivity by more than 18 times while the Sr enhances it by 25 times.

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LASER DRIVEN SECONDARY SOURCES FOR SPECTROSCOPY, PLASMA DIAGNOSTICS AND OTHER APPLICATIONS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0024
THOMAS KUEHL, BASTIAN AURAND, VINCENT BAGNOUD, BORIS ECKER, UDO EISENBARTH, DANIEL HOCHHAUS, PAUL NEUMAYER, HUANYU ZHAO, BERNHARD ZIELBAUER, DANIEL ZIMMER, JAMIL HABIB, SOPHIE KAZAMIAS, ANNIE KLISNICK, DAVID ROS, JOSEF SERES, CHRISTIAN SPIELMANN and DANIEL URSESCU

Ultra-High Intensity lasers in the regime above 100 TW have developed into a well studied tool for the preparation of plasma targets. In addition they can provide unprecedented sources of coherent soft x-rays and incoherent hard x-rays and of proton and light-ion beams. These sources are unique in their intensity and time definition. In the specific case of the laser driven x-ray laser, the coherence and narrow bandwidth of the source holds promises for additional applications. Use of secondary sources for plasma diagnostic has already been reported by several groups but in all cases still source developments are going on. The presentation will report on activities at the PHELIX laser at the GSI Helmholtz Centre, and plans and proposals for the application in combination with heavy-ion beams at GSI and the future FAIR facility.

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ADVANCED LABORATORY FOR HIGH DENSITY PHYSICS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0025
LOTFIA ELNADI, A. NASSER A. FETTOH, A. REFAIE, GALLILA A. MEHENA, HUSSEIN A. MONIEM, HISHAM IMAM, KHALED A. ELSAYED, MAGDY OMAR and SALAH H. NABY

The following sections are included: Introduction The Architecture of the High Density Short Pulse Laser Femtosecond Oscillator Booster 10 Hz Amplifier Passive Pulse Cleaner Stretcher Regenerative Amplifier Pre-Amplifier Main High Energy Amplifier Compressor Interaction Processes of HDSP Lasers with Matter Conclusion References

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HIGH ENERGY DENSITY PHYSICS: THE LASER FIELD OF TOMORROW

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0026
RICHARD R. FREEMAN

Ever since its invention, the laser has become an increasingly important tool for physics research. Indeed, the laser has made it possible to not only study many extant physical phenomena, but also to actually produce matter in conditions that don't exist in nature, or more precisely, don't exist on the earth. In this lecture, I discuss how the development of lasers that produce ultra-short (∼fsec) and ultra-intense (≥1020 W/cm2) laser pulses actually produce plasmas that are at a density and temperature that exist only in stars. In doing so I discuss some of the basics of these extreme pulses interacting with electrons, yielding surprisingly intriguing physical phenomena. Finally, I argue that this field is an essential element in any comprehensive physical research endeavor, explicitly citing its fundamental relationship with the development of clean, unlimited fusion energy power.

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CHARACTERIZATION OF DC GLOW DISCHARGE PLASMA BY HOLLOW CATHODE

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0027
K. H. METWALLY, A. H. SAUDY, M. FAROUK and M. M. EL-OKR

The following sections are included: Introduction Experimental Setup Results and Discussion Conclusion References

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THE TEXAS PETAWATT LASER AND TECHNOLOGY DEVELOPMENT TOWARDS AN EXAWATT LASER

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0028
TODD DITMIRE

We have completed the construction of a high peak power, ultrafast laser which delivers peak power in excess of 1 petawatt (1015 W). This laser, the Texas Petawatt Laser, is based on a combination of OPCPA and mixed Nd: glass amplifiers, enabling high energy operation with compressed pulse duration of <160 fs. The laser presently delivers 160 fs pulses with pulse energy exceeding 200 J. Using pulse shaping technology and broad band amplification on the front end, this laser demonstrates petawatt technology in Nd: glass amplifiers at pulse duration shorter than other Nd: glass-based petawatt facilities around the world. In my talk, I will report on the design and performance of the laser, including the technology used to access such high powers and near 100 fs compressed pulse duration…

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DENSELY PACKED 2-D MATRIX-ADDRESSABLE VERTICAL-CAVITY SURFACE-EMITTING LASER ARRAYS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0029
ABDEL-SATTAR GADALLAH and RAINER MICHALZIK

We report on design, manufacturing, and characterization of densely packed top-emitting 16 × 16 elements wire-bonded matrix-addressable vertical-cavity surface-emitting laser (VCSEL) arrays, which may find future applications such as non-mechanical particle movement with optical multi-tweezers, confocal microscopy or free-space communications with beam steering capability. The factors that control the packing density such as layer structure, mask design, and VCSEL processing are investigated, aiming to minimize the pitch between VCSELs in the array. Both wet-etched and dry-etched arrays are presented and discussed. The single transverse mode VCSELs in the two-dimensional (2-D) matrix-addressable architecture have threshold currents which vary from 0.5 to 1.6 mA and maximum output powers between 2.4 and 4 mW. A simple analysis of the parasitic ohmic resistances is made.

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XUV AND SOFT X-RAY LASER RADIATION FROM Ni-LIKE Au

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0030
WESSAMELDIN S. ABDELAZIZ and H. M. HAMED

Atomic structure data and effective collision strengths from literature for 1s2 2s2 2p6 3s2 3p63d10 and 34 fine-structure levels contained in the configurations 1s2 2s2 2p6 3s2 3p63d9 4l (l = s, p, d) for the nickel-like Au ion are used in the determination of the reduced population for the 35 fine structure levels over a wide range of electron densities and at various electron plasma temperatures. The gain coefficient for those transitions with positive population inversion factor are determined and plotted against the electron density.

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Enhanced Type-I Polarization-Entangled Photons Using CW-Diode Laser

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0031
Salem Hegazy, Mohy S. Mansour and Lotfia El Nadi

We used two type-I BBO crystals pumped by violet cw-diode laser of relatively wide bandwidth to produce entangled photons of considerable degree of purity. While diode laser serves the mobility and the low-cost of the entangled photons source, suitable temporal compensation is required in this case to recover the purity of the state. We studied also effect of tilting the two-crystal set on overlapping of the SPDC cones.

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EFFECT OF PREPARATION METHOD ON LUMINESCENCE PROPERTIES AND QUANTUM EFFICIENCY OF CdTe QDs

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0032
A. M. SAAD, M. M. BAKER, M. A. KANA and I. M. AZZOUZ

The effect of preparation procedure on the optical properties of CdTe semiconductor nanoparticles (NPs) has been investigated. CdTe NPs have been prepared via two different methods, organometallic pyrolysis method and microwave assisted aqueous based method. The nanostructure for the prepared NPs via both methods was confirmed by transmission electron microscopy, absorption and photoluminescence spectroscopy. Comparison between the quantum yield emissions of the as-prepared NPs of both methods is presented. The results shows that CdTe NPs which prepared via microwave assisted aqueous method yielded a much higher quantum efficiency (>41%). Amplified stimulated emission is investigated at room temperature (300K) and at low temperature (10K). Lifetime is also measured.

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Novel Process for Laser Stain Removal from Archaeological Oil Paintings

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0033
Lotfia El-Nadi, Osama El-Feky, Galila Abdellatif and Sawsan Darwish

Some samples of oil paintings (5 × 5 cm) were prepared on wooden panel with four types of fungi commonly encountered on oil paintings were selected for this study. Each of the fungi is associated with different colored stains. Fungus Alternaria tenuis is associated by a dense black stain, Chetomium globosum by a brownish gray stain, Aspergillus flavus by a yellowish stain, and Fusaruim oxysporum by a pinkish stain. Fungi growing on oil paintings affect the surface characteristics by forming a variety of colored patches typically composed of many complex chemical substances that are produced during metabolic processes. These colored stains may be encrusted in spores, present in mycelium or secreted to a substance such as oil paintings surfaces. While the fungal stains can sometimes be extracted with appropriate solvents, there are some stains that resist solvent extraction entirely. Developing new solvent system that might attack the paint structure, and is time consuming and requires a great deal of trial and error. Mechanical stain removal is also problematic in that it often produces abrasion of the surface, markedly deteriorating the artwork, and is extra ordinarily fine and tedious. For these reasons, we decided to examine an alternative physical technique as a new approach to deal with stain removal. Since the stains are due to the existence of fungi, we thought it a good idea to remove them by singlet oxygen. We applied the photo dynamic process through which the fungi stains were covered with organic dye derivatives in solution under controlled illumination in the lab. The samples were then irradiated by low power Laser light from a He-Ne laser, the dye will be photodecomposed and produce singlet oxygen. We report in this work the results obtained as a function of: - The concentration and types of the organic dye in solution, - The presence of certain amounts of liquids added to the solution, - The scanning speed of the laser beam on the sample surface, - The irradiation time. For each case fresh samples were used and photographed before and after the treatment. The results obtained will be speculated and discussed. This procedure was applied to the cleaning of archaeological oil paintings for the first time to our knowledge. The method could well be considered as a new field of combined science and technology applied to laser stain removal and represents a significant addition to the techniques available to art conservation.

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APPLICATION OF LASER INDUCED PLASMA SPECTROSCOPY ON BREAST CANCER DIAGNOSES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0034
A. ABD-ALFATTAH, A. A. ELDAKROURI, H. EMAM and I. M. AZZOUZ

Worldwide, millions of breast cancer cases appear each year. It ranked as the first malignant tumors in Egypt. Breast cancer patients are at increased risk of developing malignant melanoma and cancers of the ovary, endometrium, colon, thyroid, and salivary glands because of similar hormonal and genetic factors. Therefore, early diagnosis by a quick and accurate method may have a great affect on healing. In this work, we investigate the feasibility of using LIPS as a simple, technique to diagnose breast cancer by measuring the concentration of trace elements in breast tissues. The accuracy of LIPS measurements was confirmed by carrying out another elemental analysis via atomic absorption spectroscopy (AAS) technique. The results obtained via these two techniques showed that the concentration of Ca, Cu, Fe, Zn and Mn in the malignant tissue cells are significantly enhanced. A voting algorithm was built for instantaneous decision of the diagnostic technique (normal or malignant). This study instigates developing a new diagnostic tool with potential use in vivo.

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ULTRAFAST PROCESSES IN CONDENSED MATTER STUDIED WITH ULTRASHORT LASER PULSES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0035
P. A. LOUKAKUS

The high peak power and the short temporal duration of modern solid state laser systems are valuable tools to perform research on the interactions of light with matter in fundamental as well as applied and technological directions…

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ENERGY SECURITY OF INDIA — NUCLEAR ENERGY — AN INEVITABLE OPTION PRESENT PLANS AND FUTURE PERSPECTIVES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0036
JAI P. MITTAL

Recently, during last 5-10 years, India has been witnessing a very healthy economic growth of ∼6-8% pa in GDP. Energy, particularly electricity becomes a key input for sustaining such an accelerating growth…

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CHARGE MEASUREMENTS OF FRAGMENTED NUCLEI OF Si AT DIFFERENT ENERGIES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0037
M. S. EL-Nagdy, A. Abdelsalam, A. Algaood and M. Ahmed

This experimental research is a preparatory study to reflect the accuracy in identifying heavy fragmented nuclei in nuclear emulsion. The distributions of δ-rays produced by projectile fragments from 3.7A GeV 28Si in NIKFI-BR2 emulsion have been investigated. Such 28Si beam was accelerated at Dubna Synchrophastron. For sake of comparison, another source of data due to 14.6A GeV 28Si from Brookhaven National Laboratory (BNL), using different type of photographic emulsion (Fuji), is introduced. The charges of the produced projectile fragments having 2 ≤ Z ≤ 14 are deduced. This research may be important to carry out any subsequent investigation dealing with the mechanism of Si fragmentation at high energy, on the basis of the present identified charges.

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PASSIVE SAFETY FEATURES IN ADVANCED NUCLEAR POWER PLANT DESIGN

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0038
M. TAHIR, I. R. CHUGHTAI and M. ASLAM

For implementation of advance passive safety features in future nuclear power plant design, a passive safety system has been proposed and its response has been observed for Loss of Coolant Accident (LOCA) in the cold leg of a reactor coolant system. In a transient simulation the performance of proposed system is validated against existing safety injection system for a reference power plant of 325 MWe. The existing safety injection system is a huge system and consists of many active components including pumps, valves, piping and Instrumentation and Control (I&C). A good running of the active components of this system is necessary for its functionality as high head safety injection system under design basis accidents. Using reactor simulation technique, the proposed passive safety injection system and existing safety injection system are simulated and tested for their performance under large break LOCA for the same boundary conditions. Critical thermal hydraulic parameters of both the systems are presented graphically and discussed. The results obtained are approximately the same in both the cases. However, the proposed passive safety injection system is a better choice for such type of reactors due to reduction in components with improved safety.

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RESEARCH STUDIES PERFORMED USING THE CAIRO FOURIER DIFFRACTOMETER FACILITY

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0039
R. M. A. MAAYOUF

This report represents the results of research studies performed using the Cairo Fourier diffractometer facility (CFDF), within 10 years after it was installed and put into operation at the beginning of 1996. The main components of the CFDF were supplied by the IAEA according to the technical assistance project EGY/1/022. Plenty of measurements were performed, since then; yielding several publications, both in local and international scientific periodicals; and 8 M.Sc. & Ph.D. degrees from Egyptian Universities. Besides, a new approach for the analysis of the neutron spectra measured using the CFDF; applying especially designed interface card, along with its proper software program, instead of the reverse time of flight (RTOF), Finnish make, analyzer originally attached to the facility. It has been verified that the new approach cnn successfully replace the RTOF analyzer; significantly decreasing the time of measurement; and saving the reactor's operation time. A special fault diagnostic system program was developed and tested for caring and handling the possible failures of the CFDF. Besides the new developments required for the CFDF for industrial applications in wide scale, are also considered.

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K-SURFACES IN SCHWARZSCHILD GEOMETRY

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0040
AYUB FARIDI, FAZAL-E-ALEEM and HARIS RASHID

Study of the spacetime dynamics in Schwarzschild Geometry (SG) has always been in the lime light. Constant Mean Extrinsic Curvature (CMEC) hypersurfaces, also known as K-Surfaces, play an important role in SG. The talk spells out the importance of spacetime foliations and elaborates the behavior of K-surfaces for large values of K near essential singularity of Schwarzschild black hole.

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X-Rays of Heavy Elements for Nanotechnological Applications: W and Pb Ions

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0041
Sultana N. Nahar

Heavy elements can absorb or emit hard X-rays and hence are commonly implemented in various high energy nanotechnological applications. The absorptin or emission occurs mainly through the 1s-2p (Kα) transitions, and the process can be used as the source for production of radiation or electron in the applications. For enhanced productions of electrons and photons in the nanobiomedical applications, investigations have focused on the K-shell ionization of the atom or ion. This is because of the well-known rise in photoionization at the K-shell ionization threshold. However, experimental investigations to find any evidence of this rise has not been successful. We have developed a new method called Resonant Theranostics for biomedical applications, where we show that the energy for the rise is related to 1s-np, particularly to 1s-2p transitions which appear as resonances in the photoionization for heavy elements. The energy for the 1s-2p transitions varies some with the ionic state of the element and gives a narrow band resonant energy for the element. The strength of the process depends on the oscillator strength of the transitions. This report will demonstrate these through illustrations of the resonant energy range and strengths of photoabsorption due to K-alpha transitions using some elements, such as tungsten (W, Z=74) and lead (Pb, Z=82). An X-ray photon can ionize a high-Z element by ejection of a K-shell electron. This will create a hole or vacancy which, through the Auger process, will be filled out by an upper shell electron with emission of a photon. Such process at the resonant energy can lead to Koster-Kronig cascade giving out a number of photons and electrons as the element goes through various ionic states and can be modeled using the oscillator strengths. Such emissions are highly desirable in radiation therapy application. Present illustrations will include electric dipole allowed transitions for nine ionic states, from hydrogen to fluorine like ions. The 2p subshell is filled beyond fluorine. The number of transitions in each ionic state is different because of different number of 2p electrons. There are 2, 2, 6, 2, 14, 35, 35, 14 and 2 transitions in H-, He-like, Li-like, Be-like, B-like, C-like, N-like, O-like, and F-like ions respectively, with a total of 112 Kα transitions for each element to occur in the event of breaking of the ionic states, such as, due to Auger process. The Kα transitions are found to be in hard X-ray region of 57 - 63 keV (0.22 - 0.20 Å) for W, and 71 - 80 keV (0.17 - 0.16 Å) for lead.

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EFFECTS OF RADON INHALATION ON SOME BIOPHYSICAL PROPERTIES OF BLOOD IN RATS

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0042
M. F. ESSA, FAYEZ M. SHAHIN, ASHOUR M. AHMED and OMAR ABDEL-SALAM

The major source of human exposure to natural radiation arises from the inhalation of radon (222Rn) gas. Exposure to high concentrations of radon 222Rn and its daughters for long period leads to pathological effects like lung cancer, leukaemia, skin cancer and kidney diseases. The present study was performed on rats to investigate the effect of radon exposure on the absorption spectra of hemoglobin. Measurements have been performed in a radon chamber where rats were exposed to radon for 1, 5 or 7 weeks. The inhalation of radon resulted in decrease in intensity of the absorption bands characterizing the hemoglobin molecular structure with increased radon doses.

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INJECTION OF SCATTERED DISC OBJECTS INTO THE INNER SOLAR SYSTEM IN RESPONSE TO SHRINKAGE OF THE HELIOSPHERE

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0043
STEVEN FOSTER and SHAHINAZ YOUSEF

The heliosphere is the cocoon which engulfs the solar system within. It includes the planets, dwarf planets, the asteroid belt and finally the icy fragments of Kuiper belt objects and the scattered disk objects. The Kuiper belt is rather a thick donut extending from 30 AU inclined by about 0-10 degrees to the ecliptic. Beyond the Kuiper belt. Extend the scattered disc objects, SDOs to perhaps 100 AU and beyond. Most important, the SDOs are the source of periodic comets lasting less than 200 years which is of the order of the De Verie solar cycle. The boundary of the heliosphere is determined by the balance between the solar wind pressure and the stellar wind pressure. At times of reduced solar wind, the heliosphere is pushed inward. Right now we are at the bottom of the 80-120 years Solar Wolf-Gleissberg cycle where weak solar cycle series persists. During the period 1890-2010, the heliosphere oscillated between 75-125 AU. This paper proposes a “pump mechanism” in which scattered disc objects are injected into the inner solar system during times of low solar cycles and the conjunction of Neptune with the Hydrogen wall. We suggest that the inward movement of the heliosphere inject short period comets into the inner solar system. A possible orbital relationship exists between Neptune (164.3 years) and two Wolf-Gleissberg cycles (165 years). As the solar wind has been reduced at present, we suggest an increased frequency of these short period comets after allowing for delay times.

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Transverse momentum spectra of alpha-particles as projectile fragments in Nucleus - Em Interaction at (4.1 - 4.5) A GeV/c

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0044
S. S. Abd El-Aziz, M. Mohery and M. H. Soleiman

The transverse momentum spectra (pT-distribution) of the relativistic α-aparticles in the projectile fragmentation resulting from the interaction of 12C, 16O, 28Si (4.5 A GeV/c), and 22Ne (4.1 A GeV/c) projectiles with emulsion have been analyzed and modeled. The behavior of PT-adistribution of the emitted α-fragments was found to be independent of the types of projectile and also of the energy of the projectile. All of the pT-distributions have a tail, at large transverse momentum. Single Maxwell-Boltzmann model (M-B) is not sufficient to describe this behavior, but a superimposition of two Maxwell-Boltzmann (M-B) models with different transverse momentum spectra PTMean, and with different temperatures is adequate. The linear fitting method has a drawback that the total model resulting from superimposition of two M-B models is shifted toward larger transverse momentum regions and doesn't completely fit with the total PT-distribution of α-fragments.

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LIGHT-STRANGE MESONS DECAYS IN THE QUARK MODEL

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0045
A. M. Yasser, E. M. Hassan, M. A. Fawzy and M. A. Allosh

The 3P0 model is used to investigate light-strange mesons strong decays. Decay amplitudes and decay widths are evaluated by using relativistic and non-relativistic simple harmonic oscillator (SHO) wave-functions. Numerical results are given for allowed open-flavor decay modes for and mesons. The results for the relativistic model are in good agreement with the recent published data.

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SURPRISING RAPID COLLAPSE OF SIRIUS B FROM RED GIANT TO WHITE DWARF THROUGH MASS TRANSFER TO SIRIUS A

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0046
SHAHINAZ YOUSEF and OLA ALI

Sirius was observed in antiquity as a red star. In his famous astronomy textbook the Almagest written 140 AD, Ptolemy described the star Sirius as fiery red. He curiously depicted it as one of six red-colored stars. The other five are class M and K stars, such as Arcturus and Betelgeuse. Apparent confirmation in ancient Greek and Roman sources are found and Sirius was also reported red in Europe about 1400 years ago. Sirius must have changed to a white dwarf in the night of Ascension. The star chapter in the Quran started with “by the star as it collapsed (1) your companion have not gone astray nor being misled (2), and in verse 49 which is the rotation period of the companion Sirius B around Sirius A, it is said” He is the Lord of Sirius (49). If Sirius actually was red what could have caused it to change into the brilliant bluish-white star we see today? What the naked eye perceives as a single star is actually a binary star system, consisting of a white main sequence star of spectral type A1V, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B. The red color indicates that the star seen then was a red giant. It looks that what they have seen in antiquity was Sirius B which was then a red giant and it collapsed to form a white dwarf. Since there is no evidence of a planetary nebula, then the red Sirius paradox can be solved in terms of stellar evolution with mass transfer. Sirius B was the most massive star which evolved to a red giant and filled the Roche lobe. Mass transfer to Sirius A occurred through the Lagrangian point. Sirius A then became more massive while Sirius B lost mass and shrank. Sirius B then collapsed abruptly into a white dwarf. In the case of Algol, Ptolmy observed it as white star but it was red at the time of El sufi. At present it is white. The rate of mass transfer from Sirius B to Sirius A, and from Algol B to A is estimated from observational data of colour change from red to bullish white to be 0.0021 and 0.0024 M⊙/yr respectively.

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EVALUATION OF RADIOACTIVITY CONCENTRATION IN TILAPIA NILOTICA AND RADIATION DOSE TO EGYPTIAN POPULATION

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0047
HANNAN H. AMER and ENAS H. EL-KHAWAS

One of the three goals of the United Nations for sustainable food security is to ensure that all people have access to sufficient, nutritionally adequate, and safe food. The study was carried out to evaluate the Uranium (238U) and thorium (232Th) concentration in the Bolti (Tilapia nilotica) fish collected from Nasser Lake by using two different types of detectors CR-39 SSNTDs and gamma spectroscopy. The annual intake of Bolti fish was estimated on the basis of their average annual consumption. Calculations were also made to determine the effective dose to an individual consuming such diet.

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SOLAR FORCINGS ON NILE AND EARTHQUAKES

U+1F512 & doi: https://doi.org/10.1142/9789814504898_0048
SAAD MOHAMMED AL-SHEHRI, ISMAIL SABBAH, SHAHINAZ MOUSTAFA YOUSEF and MAGDY Y. AMIN

Nile and earthquake periodicities are examined in the light of solar and geomagnetic periodicities in order to uncover the role of the sun in initiating such terrestrial phenomena. The Nile periodicities under considerations covers the period 622-1420 AD. 1749- 1800 and 1870-1945 and are taken from an earlier paper by Yousef and El-Rae (1995). It is found that 11 yr and 21 yr solar periodicities affected the White Nile originating from the Equatorial plateau. On the other hand the Blue Nile arising mainly from Lake Tana in Ethiopia was affected mostly by the 3.3 yr, 2.9 yr, 2.7 yr, and the 2.52 yr periodicities. Such short periodicities are also present in cosmic rays. This is fairly true as during weak solar cycles series at the bottom of the 80-120 year Solar Wolf-Gleissberg Cycles, the level of the second to last of the weak cycles rise and fall coherently with full solar cycles with a correlation coefficient of about 0.9. Rain over Ethiopia is affected by the Monsoon precipitation which is related to the quasi biennial oscillations QBO of the equatorial zonal wind between the easterlies and the westerlies in the tropical stratosphere with a mean period of 29 months. We propose that the QBO are stimulated by the 2.52-2.48 yr solar periodicities. The 2.52 and 2.48 yr periodicity is strong in odd solar cycles 21 and 23. Generally speaking, it looks that different solar periodicities are space-time dependant and that they affect different regimes of terrestrial responses. In the case of earthquakes, we think that they are related to geomagnetic storms initiated by solar stimuli. Several solar periodicities are found in earthquakes. We postulate that electric currents in the ring current and in the ionosphere induce surface as well as deep electric currents in the magma thus produce motion and disturbances of the plates and the magma leading to earthquakes and volcanoes.

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