Open Access Original Research Article

Method for Constraining Light Speed Anisotropy by Using Fiber Optics Gyroscope Experiments

A. Sfarti

Physical Science International Journal, Page 161-175

The Mansouri-Sexl theory is a well known test theory of relativity. Mansouri and Sexl dealt with the theory of the Michelson-Morley, Kennedy-Thorndike and Ives-Stilwell experiments but left out the very interesting Sagnac experiment. In the following paper we will present a novel way of detecting anisotropy effects in   via a reenactment of the Sagnac experiment using fiber optic gyroscopes (FOG) where  is the length of the fiber and  is the angular speed of the FOG. We show how the fiber optics gyroscopes are used for constraining light speed anisotropy in the framework of the Mansouri-Sexl test theory.  We also show an interesting amplification effect due to the use of the Mansouri-Sexl slow clock transport equations in conjunction with FOGs. Our paper is divided into four main sections: in the first one we give an overview of the Mansouri-Sexl test theory of special relativity, in the second one we give a historical perspective of the Sagnac experiment, in the third section we formulate the Mansouri-Sexl theory for the Sagnac experiment and we conclude with experimental setup and results.

 

Open Access Original Research Article

Electronic Structure with Rovibrational and Dipole Moment Calculations of the LaS Molecule

M. Korek, H. Hammour

Physical Science International Journal, Page 176-190

The potential energy and the dipole moment curves have been investigated for the 23 lowest electronic states in the  representation of the molecule LaS via CASSCF. Multireference CI calculations (single and double excitations with Davidson corrections) were performed by using Gaussian basis sets for the two considered atoms. The harmonic frequency we, the internuclear distance re and the electronic energy with respect to the ground state Te have been calculated for 23 electronic states along with the rovibrational data Ev and Bv. Nineteen electronic states have been studied here for the first time. The comparison of the investigated values with the theoretical and experimental results available in the literature shows a very good agreement.

 

Open Access Original Research Article

Study of Compactons and Solitons Using Finite Element Method

S. Asadollahi Zowj, A. Azizi, A. Asrar

Physical Science International Journal, Page 191-204

In this research, we study some properties of compactons using Finite Element Method (FEM). This method is complicated for programming and very time consuming; but it is an accurate method. Using this method, we studied soliton properties and obtained results were acceptable. Then we studied compactons; Compactons are solitons with finite width or on the other hand solitons with no tail. This defined property for compactons was not observed in our simulation. It seems that breaking of compacton occurred regarding the entity of compacton equations, not by numerical error. In compactons- anti compactons collision, particle-like manner was not observed at all during this research. Perhaps it is due to suddenly vanishing of compactons on both ends.

 

Open Access Original Research Article

The Effect of Hydrostatic Pressure on the Electronic Properties of TlBr and TlCl Radiation Detectors

N. Amrane, M. Benkraouda

Physical Science International Journal, Page 205-217

We present first principles calculations of the electronic properties of TlBr and TlCl binary semiconductor compounds. The dependences on hydrostatic pressure of these properties (band structure, density of states, electronic charge density) are successfully calculated using self-consistent scalar relativistic full potential linear augmented plane wave method (FP-LAPW) within the generalized gradient approximation (GGA). The GGA corrections yield only minor improvement, whereas Engel-Vosko approximation gives a significant improvement to the band gap. The results are compared with previous calculations and with experimental measurements, we found good agreement with our calculations.

 

Open Access Original Research Article

Diagnostic of Laser Induced Li II Plasma

Banaz Omar, August Wierling, Heidi Reinholz, Gerd R¨opke

Physical Science International Journal, Page 218-227

Spectral line broadening in dense plasmas is investigated for lithium He-like ion based on a microscopic quantum-statistical approach. By using thermodynamic Greens function, perturber-radiator interaction, plasma correlation and screening effects are taken into account. Ions are treated in quasi-static approximation, leading to a Stark effect by the surrounding perturbers microfield. Stark broadening of Li II (2p3P2;1;0−2s3S1) 548 nm line is calculated, plasma parameters such as temperature and free electron density for the expanding Li plasma after 60 ns from laser irradiation are analyzed ( Doria, D., Kavanagh, K.D., Costello, J.T., and Luna, H. (2006) Meas. Sci. Technol., 17, 670-674). The estimated spatial electron density and temperature ranges are ne = (0.25−2)×1024 m −3 and T ≈ (2−3.5) eV, respectively. The dependence of plasma parameters on the line width is investigated. A good agreement is shown by comparing our calculation with the published measured profiles.

Open Access Original Research Article

Open Access Original Research Article

Unifying the Scaling Relations in Galactic Bulges – an Implication of Bulge Formation

Chan Man Ho

Physical Science International Journal, Page 248-255

Aims: I present the derivation of some important scaling relations in galactic bulges by using a simple model of bulge formation.

Methodology: If the radiation pressure of the bulge suppresses its accretion of mass, together with the bulge luminosity-mass relation and the supermassive black hole (SMBH)- velocity dispersion relation, we can obtain a set of scaling relations such as those relating the mass of SMBH to bulge mass and luminosity, the Faber-Jackson and the fundamental plane relations.

Results: All these derived scaling relations agree with the empirical fittings from the observations.

Conclusion: All the scaling relations derived are consistent with the observational data. Therefore, the radiation pressure of the bulge provides a significant role to connect all the scaling relations together.

 

Open Access Review Article

Power Transformer Life Management; Relevance to Nigerian Power Industry

A. A. Abdelmalik

Physical Science International Journal, Page 236-247

Non-expansion of Nigerian grid network resulted in Increasing loading of the existing power equipment. Attempt to reduce life cycle costs resulted in decrease maintenance expenditures and postponement of investments. These resulted in higher failure rates and increasing risk of major failures. Frequent failure of power equipment at the transmission substations and distribution stations in Nigeria has prompted the need to establish a system that can give advance information on the state of power equipment in service. The ineffective monitoring system has also resulted to high cost of equipment maintenance. One way of achieving reduced maintenance cost is the use of real time condition monitoring technique. This paper discussed factors responsible for power equipment deterioration and failure, and the concepts of condition-based monitoring system. Typical scenario of online transformer monitoring is reviewed. A real time life management system which is under development for the monitoring of the health of power transformers at the substations and distribution stations is discussed. The objective of the ongoing project is to secure the quality of the generated electrical energy with minimized cost of expenditures for services (life management). This system will enable asset managers monitor their equipment in the field. This will save cost of asset maintenance and ensure a better service delivery to electricity end‑users.