Jordan Journal of Physics

Time Dependent Spectral Ratio Technique for Micro-seismic Exploration in the Niger Delta Region of Nigeria

2024-09-15T10:45:10+03:00

Abstract: Since the discovery of the hydrocarbon micro-tremors, there have been numerous efforts to understand the causes of these microseisms related to oil and gas. A spectral ratio (SR) time-dependent equation was derived based on geological principles. The equation showed tremendous success in analyzing multi-layered geological terrain and estimating the spectral ratio in the Niger Delta region of Nigeria. This study seeks to develop a reliable model using standard seismic reflection data to analyze microseismic datasets from hydrocarbon reservoirs. Type A-SR acts over a longer duration and can be used to determine hydrocarbon reservoirs. Type B-SR acts in a short time with maximum impact. It can be used to determine gas condensate flow in the hydrocarbon reservoir. It is recommended that this technique be applied in real time to ascertain its accuracy.

A Study of the Abundance of Aluminium in Massive Stars

2024-09-15T10:48:53+03:00

Abstract: This study presents the results of the calculation of the mass fractions of isotopes from hydrogen to nickel during the entire core burning phases of a 25 M_⊙ star. A simple stellar model was used, considering four main parameters: temperature, density, initial composition, and time, without accounting for mass loss or mixing. The mass fractions of the isotopes were calculated using the open-source package NucNet Tools and the updated reaction rates from the JINA Reaclib database. A comparison of our results with existing similar data is performed and acceptable agreement is conspicuous. Hydrodynamic conditions in massive stars favor the production of ²⁶Al, therefore particular attention was given to the isotopes ²⁶Al and ²⁷Al and the ratio of their mass fractions for comparison with the literature. The averaged value of the controversial during the star's lifetime is found to be 1.68×10^-4.

The Bound Band Structure in a Strong Attractive Dirac Comb

2024-09-15T11:01:12+03:00

Abstract: The Dirac comb problem in quantum mechanics is revisited by estimating its energy band structure, including the band gap, bandwidth, and the effective mass at band edges. The case of an attractive strong Dirac comb potential is considered. Our findings show the existence of a single bound energy band state, which is flat with a small width and a large effective mass at both of its edges; positive at its lower edge and negative at its upper edge.

Some Phenomenological Aspects of Higgs Production in Two Leptons and bb ̅ Final State Processes

2024-09-15T11:04:23+03:00

Abstract: We present a partonic-level analysis of the two leptons and final states processes at the ILC . This process contains Higgs production with an electron-positron pair, where the Higgs decays into a quark pair as a sub-process, . We tried to isolate this sub-process with a minimum set of cuts. Particularly, cross-sections are estimated at different energies, and the main distributions of kinematic variables characterizing the process are derived using the software Calchep [16]. The results provide information on signal and background characteristics for different ILC operating stages.

Surface Texturing of Silicon Wafers by Two-step Ag-assisted Etching Process with New NSR Solution

2024-09-15T11:06:50+03:00

Abstract: Solar cells made of monocrystalline silicon can convert more solar energy into electrical energy if the cells can absorb greater amounts of light. Recently, it has been observed that metal-assisted catalyzed etching (MACE) is a good technology for manufacturing micro and nanostructures on silicon substrates. In this work, we use silver as a catalyst in a two-step metal-assisted etching process followed by a rebuilding nanostructure (NSR). We study the effect of changing the parameters of the second step in the MACE process (concentrations of etching solution materials, temperature, and reaction time), where black silicon was obtained with a reduced reflection of 3% without the NSR process. We tested the effect of two types of alkaline solutions in the NSR process on the surface structure of silicon. After performing an NSR operation with sodium hydroxide solution, the field emission scanning electron microscopy (FESEM) image shows a surface with upright pyramidal structures intertwined with deep cavities, and with a reflectance of 10.74%. However, after performing the NSR process with a solution of sodium silicate, the FESEM image shows a rough surface with non-overlapping pores of small cross-sections, achieving a reflectance of 8.65% within the wavelength range of 550-850nm.

Structural and Luminescent Characteristics of Divalent Europium Activated Barium Aluminate with the Tridymite Structure Synthesized by the Sol-Gel Technique

2024-09-15T11:22:04+03:00

Abstract: In this study, alkaline earth aluminates were investigated as potential hosts for new blue luminescent materials with nanoparticles. Ba_1-xEu_xAl₂O₄ with the stuffed tridymite hexagonal structure was successfully synthesized at 900 °C under controlled sol-gel conditions. Divalent europium was effectively used to activate this host material, producing a brilliant blue-emitting phosphor. Its spectral photoluminescence at 408 nm appears to be in a region close to the laser blue region, with chromaticity coordinate values suitable for the standard blue of the PAL TV system.

Influence of Applied Discharge Voltage and Gas Flow Rate on Nickel Plasma Jet Parameters Diagnosed by Optical Emission Spectroscopic Technique

2024-09-15T11:34:46+03:00

Abstract: In this work, we measure the plasma parameters by using an AC high-voltage power supply that generates a non-thermal plasma jet system at atmospheric pressure. A nickel (Ni) metal strip, with dimensions of 1.5 × 10 cm², was connected to the anode electrode of the AC power supply. This nickel strip was immersed in a flask with a small amount of distilled water positioned below the plasma plume nozzle. Optical emission spectroscopy (OES) was used to diagnose the plasma system at different argon gas flow rates (1-5 L/min) and varying applied voltage values (11-15 kV). It is significant to know the processes accompanying plasma generation to measure their parameters which include the electron temperature (T_e), electron number density (n_e) of the plasma, Debye length (λ_D), and plasma frequency (f_p). Our results showed an increase in the intensity of spectral lines with the increase in applied discharge voltage (11-15 kV). The maximum peak for ArI was observed at a wavelength of 811.531 nm, and the maximum peaks for nickel (Ni) were observed at wavelengths of 285.21 and 519.70 nm. Also, the results indicated a gradual increase in electron temperature (T_e) and electron density (n_e) values at the applied voltage of 0.403-0.468 eV. Likewise, the electron density (n_e) was in the range of (11.486-13.851) × 10¹⁷ cm^-3.

First-principles Study on Structural and Electronic Properties: The Li Based of Full-Hesulter Alloys LiGa2Ir

2024-09-15T11:38:29+03:00

Abstract: Due to their excellent electronic properties, full-Heusler compounds have become one of the most interesting families of alloys in superconductivity. More recently, computational methods have been actively employed to support the rapid discovery of new complete Heusler alloys by identifying stable compositions with desired properties. Therefore, we investigated the stability, structure, and electronic properties of the lithium-based Heusler compound LiGa₂Ir using first-principles calculations. We explored the effects of exchange-correlation, namely Perdew-Burke-Ernzerhof (PBE), PBE+U, and Tran-Blaha modified Becke-Johnson potentials, as well as the effect of heavy metal spin-orbit coupling on these Heusler compounds. The results show that LiGa₂Ir is energetically stable, and the obtained lattice parameter value (a = 6.0927 Å) agrees with the experimental results. LiGa₂Ir exhibits metallic behavior under all three exchange-correlation estimates. A much stronger spin-orbit coupling effect is observed for electronic states with energies below the Fermi level E_F, especially in the Tran-Blaha modified Becke-Johnson approximation. Significant spin-orbit coupling effects are evident from the total and partial density of states figures, especially in the energy range from -4.5 eV to -2 eV. The contributions from Ir-d and Ga-p orbitals are the largest, while the contribution from the Li atom is small. Our findings will benefit future theoretical and practical work on lithium-based full-Heusler alloys.

Indicators of Radioactive Contamination by Radionuclides for Samples of Plant Fertilizers and Pesticides

2024-09-15T11:45:34+03:00

Abstract: This study aims to evaluate the radiation levels resulting from plant fertilizers and pesticides in Babylon City, Iraq. The specific activity of the studied radionuclides (e.g. ²³⁸U, ²³²Th, and ⁴⁰K) was identified using the spectroscopy approach of the sodium-activated iodide thallium (NaI (Tl)) with dimensions of 3" × 3". The resulting data revealed that the specific activities for the aforementioned nuclides were 6.254 Bq/kg, 4.3694 Bq/kg, and 112.751 Bq/kg, respectively. The results indicated that the average radiation hazard metrics for fertilizers (i.e., gamma index, alpha index, absorbed dose rate, ambient dose equivalent rate, annual gonadal dose equivalent, and excess lifetime cancer risk) were lower than the reference levels.

An Investigation into Properties for (_66^156)Dy Isotope Using IBM-1 and IVBM Model

2024-09-15T11:53:11+03:00

Abstract: The isotopes in the O (6) region were investigated. The positive ground-state band of nuclei was calculated using the interacting boson model ‎(IBM-1) and the interacting vector boson model (IVBM). The negative parity band energies of the above isotope were calculated using (IVBM) only. We plotted the ratios ( , ) and the E-GOS curve as a function of the spin (I) to investigate the properties of the yrast band. Accordingly, the best-fit values of the parameters were used to construct the Hamiltonian, and the electromagnetic transition probability B(E2) of this nucleus was determined. Theoretical energy levels of dysprosium-156 isotope with a neutron number N = 90 and spin parity up to were obtained using the MATLAB-20 simulation program. A comparison of these calculated energy levels with the corresponding experimentally measured ones shows a good agreement. The results also ‎draw our attention to the fact that the nucleus of interest deforms and exhibits gamma-instability ‎properties.

Dose Measurement and Cancer Risk from Natural Radioactivity in Cleaning Powders at Kurdistan Markets, Iraq

2024-09-15T11:58:04+03:00

Abstract: The Kurdistan region of Iraq has seen a rise in the use of cleaning powders due to their favorable effects on health. However, various levels of radioactive isotopes, including ²³⁸U, ²³²Th, and ⁴⁰K, can be found in the ore used to make some cleaning powders. Therefore, washing powder is regarded as one of the environmental sources of radionuclides and radioactivity. In this study, 25 samples of ordinary cleaning powder were analyzed to estimate the specific activities of ²³⁸U, ²³²Th, and ⁴⁰K using a gamma-ray sodium iodide NaI(Tl) detector. The mean activity concentrations of ²³⁸U, ²³²Th, and ⁴⁰K were found to be 0.27±0.027, 1.881±0.149, and 19.213±0.899 Bq.kg^-1, respectively, which are well below the recommended values set by UNSCEAR 2000: 32, 45, and 400 Bq/kg for ²³⁸U, ²³²Th, and ⁴⁰K, respectively. The radiological hazard parameters determined for each sample of detergent were also found to be lower than the maximum allowable values recommended by international organizations. Therefore, cleaning powders sold in the Kurdistan region markets pose no radioactive risk to users.

Radon Gas Detection of Soil Samples in Primary Schools at Najaf City, Iraq

2024-09-15T12:01:42+03:00

Abstract: The radon concentration, specific activity of ²²⁶Ra (C_Ra), and ²³⁸U concentrations (C_U) in soil samples from 100 primary schools of Al-Najaf province, Iraq, were measured to determine the safety of students and staff using the CR-39 nuclear track detector based on the sealed can technique. The mean values of ²²²Rn concentration in the air space of the container (C) and the soil sample (C_Rn) were 23.53±1.149Bq/m3 and 960.38±47 Bq/m3, respectively. The mean values of C_Ra and C_U were 0.035±0.002 Bq/kg and 0.043±0.002 ppm, respectively. The ²²²Rn,²²⁶Ra, and ²³⁸U concentrations were lower than the worldwide level. Radiological parameters such as annual effective dose (AED) and radon exhalation rate per unit mass (E_M) and per unit surface (E_S) also were determined. The results indicate normal levels for these parameters, except for higher values of AED in some primary schools, according to UNSCEAR data.