Enhanced uin Reflectivity from Laser – Produced Plasmas with Hot Spots

Muhammad Bawa’aneh

    Total Funding: 3299                                  Funded by:Hashemite University

    Acceptance Date: 3/5/2000                          Duration of Project : 6 months

ABSTRACT

      Stimulated Brillouin scattering (SBS) is one of very few obstacles facing inertial confinement fusion to occur. SBS is a parametric instability that occurs in plasma from the resonant decay of laser waves into scattered electromagnetic waves and ion acoustic modes of the plasma. Experiments carried out in various laboratories show SBS emissions at levels consistently higher, by several orders of magnitude, than those predicted by convective theory. In this project we are trying to reduce the gap between theoretical results and those obtained in labs by trying to understand the nature of SBS from different regimes of plasma, where we considered, for example, magnetized plasma and plasma with temperature inhomogeniety, which we believe will improve our understanding of the process and improve theoretical models that we use to interpret experimental results. We use both fluid and kinetic models of the plasma to study different phenomena affecting, or somehow related to, SBS.

           Funded Projects By HU:

            Other Projects:

        *Faculty: Science and Arts /  Physics

      * Specific Specialization: Theoretical and computational plasma physics.

 Adaptation of ECOSYS-87 to Jordan’s Environment Conditions to Make a Rapid Hazard Assessment Following a Nuclear Accident

Gamal AL Gundi

Muhammad Bawa’aneh

    Total Funding: 8250                                  Funded by:Hashemite University

    Acceptance Date: 17/9/2003                              Duration of Project : 24 months

ABSTRACT

One of the lessons to be drawn from the Chernobyl leakage accident was the importance of a coherent, harmonized and sensitive response to nuclear emergencies.  A mechanism for achieving such a response is the development of a comprehensive and integral decision-support-system that is generally applicable across Jordan.  Thus the objectives of the project will be:-

1- Collection and analysis of the existing data pertinent to Jordan in respect to the determination of soil-water-plant transfer factors.

2- Adaptation of the ECOSYS-87 to fit the prevailing environmental conditions in Jordan.

3- Establishment of background radiation levels before a radionuclide deposition takes place as the ECOSYS-87 model does not take that into account.

          Funded Projects by HU:

          Other Projects:

     *Faculty: Science and Arts / Physics

     * Specific Specialization: Radiation physics.

Environmental effects on dielectric behavior of Polyvinyl Chloride

Saadi Abdul Jawad *

Hayel Shehadeh ٍِِ

    Total Funding: 2700                                   Funded by:Hashemite University

    Acceptance Date: 30/9/2002                                Duration of Project : 12 months

ABSTRACT

    One of the lessons to be drawn from the Chernobyl leakage accident was the importance of a coherent, harmonized and sensitive response to nuclear emergencies.  A mechanism for achieving such a response is the development of a comprehensive and integral decision-support-system that is generally applicable across Jordan.  Thus the objectives of the project will be:-

1- Collection and analysis of the existing data pertinent to Jordan in respect to the determination of soil-water-plant transfer factors.

2- Adaptation of the ECOSYS-87 to fit the prevailing environmental conditions in Jordan.

3- Establishment of background radiation levels before a radionuclide deposition takes place as the ECOSYS-87 model does not take that into account.

         Funded Projects by HU:

         Other Projects:

     *Faculty: Science and Arts /: Physics

    * Specific Specialization: Polymer Physics

Measurements of Dielectric Behavior of Human Blood

Saadi Abdul Jawad *

Hayel Shehadeh ٍِِ

    Total Funding: 36410                                  Funded by:Hashemite University

    Acceptance Date: 7/2000                                      Duration of Project : 12 months

ABSTRACT

Blood units from donors are usually collected in special containers ( plastic bags) containing anticoagulants and preservatives to prolong the shelf life of blood cells . the most commonly used solution today is the anticoagulant-preservative mixture of citrate -phosphate -dextrose-adenine solution (CPDA-1) , Citrate is used as a  chelating agent to remove Ca⁺⁺  and prevent clotting , Phosphate buffer to control PH , and Dextrose to maintain cell metabolism . CPDA-1 also contain Adenine which helps replenish ATP . Blood collected in CPDA-1 may stored up to 35 days at 1- 6 ⁰ C . Because red cell metabolism continues during storage , biochemical changes take place in stored blood. . Dielectric measurements on fresh and stored blood  was investigated in the frequency range 1 Hz up to 10⁶ Hz . Measurements of different ions concentration in the blood was determined to correlate the dielectric behavior of human blood  with the variation of  blood components . The measurements were carried out on different blood samples stored for 40 days . The measurements were performed each day on the same type of blood .  Different dielectric parameters were measured  such as relative permittivity , loss factor , electric modulus and  dissipation factors . All these parameters were measured as a function of frequency  and aging time.

         Funded Projects by HU:

         Other Projects:

      *Faculty: Science and Arts /  Physics

*Specific Specialization: Polymer Physics

Theoretical Analysis of Elastic and Transfer Nuclear Reactions of Heavy Ions at Intermediate and High Energies

Rashad Ibrahim Badran

    Total Funding: 21000                                           Funded by:Hashemite University

    Acceptance Date: 30/7/1998                                Duration of Project : 36 months

ABSTRACT

Analysis of measured cross-sections of heavy-ion reaction in the form of energy spectra and angular distributions provides a useful probe for understanding structural properties of the nuclei involved as well as the mechanism of their interaction. Extensive studies of heavy-ion elastic, inelastic and transfer reactions have been conducted during the past three decades, as heavy-ion beams of increasingly higher energy became available. The progress of this work had led to continuous improvement in the experimental and theoretical techniques used, and to a better understanding of these inter-related processes. The furthering of this work offers a wide scope for experimental and theoretical work.

A first advancement in understanding the basic features of heavy-ion collisions was achieved in the fifties by Blair. The Blair sharp cutoff model for elastic scattering accounted for both the diffractive effects of strong absorption and the semiclassical nature of the projectile motion in the Coulomb field. The “quarter-point” recipe gave a first glimpse of the interplay between the refractive Coulomb and the diffractive nuclear effects. This treatment was generalized to include single-step inelastic diffraction scattering leading to collective nuclear states. This was the inelastic diffraction model, which was based on the "adiabatic” approximation according to which, excited nuclear states were treated as energy-degenerate. The success of this model in analyzing wide range of inelastic alpha-particle scattering experiment and in showing the intimate relationship between elastic and inelastic processes lead to the development of a more general treatment of heavy-ion inelastic scattering by Austern and Blair. This latter treatment based on the general expression for direct reaction amplitudes given by the distorted wave Born approximation (DWBA) and the collective description of nuclear states and through introducing number of approximations, which are best justified when the projectile is strongly absorbed by the target nucleus, a generalized inelastic diffraction formalism was derived. This theory accounts for single as well as multi-step inelastic processes and reduces to the inelastic diffraction model as a special case. One of the simplifying results of the Austern-Blair theory is the parameterization of the radial integral in view of the smooth dependence of the scattering matrix elements on orbital angular momentum in heavy-ion elastic scattering. This theory brings out the intimate relationship between elastic and inelastic processes to all orders of excitation. This is achieved, in part, by a virtue of dealing directly with the elastic scattering matrix elements rather than with the explicit optical potential.

The established importance of the relation between elastic and quasi-elastic processes, such as inelastic scattering, made the former process the subject of extensive experimental and theoretical investigations. In view of the smooth angular momentum dependence of the S-matrix elements for elastic scattering in the presence of strong absorption, many of these investigations were based on numerical or analytical treatments of partial wave expansion formalism for elastic scattering cross-section.

Part of my concern is related to the analysis of angular distribution of elastic scattering based on the strong absorption model (diffraction model).

Numerical treatment of the DWBA amplitude for the inelastic and transfer heavy-ion reactions were also employed in the analyses of experimental data. In one approach, the magnitudes as well as the phases of the radial integral in the DWBA amplitude were parameterized in angular momentum space of the entrance and exit channels. This was done by fitting the assumed distribution functions to actual DWBA calculations. This method was also applied by Frohlich et al in analyzing alpha-transfer reactions produced by bombarding ⁴⁰Ca targets with different heavy-ions. The measured cross-sections in this case were in the form of continuous energy spectra corresponding to the population of highly excited continuum residual states.

Mermaz used a numerical treatment of the DWBA amplitude in analyzing several transfer reactions leading to discrete as well as continuum states. His method is simpler, but less rigorous, than the previously described method, in that he directly combines McIntyre type of parameterization of the S-matrix elements with a suitable realistic form of the Austern-Blair expression for the radial integral. The main approximation in this treatment is the assumption that the expression for the radial integral given by the Austern-Blair theory for inelastic scattering can be used for transfer reactions.

In a most recent work, Badran et al¹⁴ have improved the approach of Mermaz by considering the nuclear refractive effects as represented by the nuclear phase factor as well as the imaginary term. This gives an obvious justification to the importance of nuclear phase factor in off-setting the effects of Coulomb repulsion and hence pulling the angular distribution towards forward angles. However, an expression for statistical level densities was used to populate high states in this work and other previous works. Strictly speaking, this expression for the level densities is not the appropriate one, since transfer reactions do not populate states in a statistical fashion. According to the multi-step compound formalism, only states in which all single particles remain in bound states may be populated. The resulting density of states has been given by Oblozinski for the case in which only one type of particle (proton or neutron) is transferred, and was successfully used by Mermaz in calculations of ejectile spectra from reactions where the projectile velocity is comparable with the Fermi velocity of the transferred particle. In the future work the Oblozinski form of level density together with other level densities (like William’s form of level density) will be tested and the results will be compared with the most recent calculations.

Some of this work has been conducted on the continuum spectra of the transfer reaction ⁵⁶Fe(⁷Li, ⁴He) ⁵⁹Co* at 50 & 68 MeV.

         Funded Projects by HU:

                 Other Projects:

            *Faculty: Science and Arts /  Physics

     *Specific Specialization:

Global Radiation Attenuation by Dust and Polluted Air in Zarqa city/Jordan

Mhammad Barakat

Nada Jallo

    Total Funding: 1000                                                Funded by:Hashemite University

    Acceptance Date: 18/2/2004                                   Duration of Project : 4 months

ABSTRACT

   Solar radiation attenuation in zarqa City (Latitude 32.2N and Longitude 36.35E) is estimated by comparing the calculated extratrrestrial irradiance relative to the measured global irradiance using GS1 Solarimeter. Of all the atmospheric components, aerosols are an important attenuater of the solar radiation. Link’s turbidity factor T_L takes into account the spectrally integrated attenuation that aerosols as well as water vapor produce on solar rays. Therefore the calculation of this factor for Zarqa city is important. The evaluation of T_L requires a knowledge of the optical thickness which inturns requires a knowledge of air mass, which represts the proportion of atmosphere that light must pass through before striking the earth relative to its overhead pathlength.

   The computer programe for extraterrestrial  radiation calculation is completed  now. The air mass calculation using several methods is calculated also. We are in a stage of calculating the optical thickness so that we will be able to calculate T_L   which is the final step of our work.

  But execuse me to say  That I haven’t receive the computer yet and I am using my personal computer.

         Funded Projects by HU:

         Other Projects:

            *Faculty: Science and Arts /  Physics

      *Specific Specialization :Laser Physics.

Bound and scattering state wave functions for velocity-dependent potentials

Mahmoud AL Gagoub*

    Total Funding: 21000                                            Funded by:Hashemite University

    Acceptance Date: 30/7/1998                                  Duration of Project : 36 months

ABSTRACT

A relation linking the normalized s-wave scattering and the corresponding bound-state wave functions at bound state poles is derived. This is done in the case of a non-local, velocity-dependent Kisslinger potential. Using formal scattering theory, we present two analytical proofs of the validity of the theorem. The first tackles the non-local potential directly, while the other transforms the potential to an equivalent local but energy-dependent one. The theorem is tested both analytically and numerically by solving the Schrodinger equation exactly for the scattering and bound state wave functions when the Kisslinger potential has the form of a square well. A first order approximation to the deviation from the theorem away from bound state poles is derived analytically. Furthermore, a proof of the analyticity of the Jost solutions in the presence of a non-local potential term is given.

           Funded Projects by HU: