We study processes in which neutrinos can be generated as a possible source for the neutron emission form neutron stars. In the high energy limit and in the range em < E < Mw the CROSS sention for ge →ev`v is analytically calculated. We also calculate the CROSS SECTION for gg→v`v in the noncommutative space. The obtained results in comparison with the CROSS SECTION for gg→v`v and gg→gv`v in the commutative space could be quite important in the astrophysics. As a result the CROSS SECTION for gg→v`v in the noncommutative spaces, in the range A = 100- 300Ge V, is comparable with its counterpart in the commutative space.  

In this research, a plasma column with a circular CROSS SECTION magnetized by a DC-axial magnetic field is investigated as a plasma antenna. The radar CROSS-SECTION and the SCATTERING pattern of radio waves landing to the antenna are studied. The present plasma antenna, in addition to advantages such as lightness, less thermal noise at satellite frequencies, etc., compared to metal antennas, due to its simple structure and ease of rearrangement by various characteristics such as the intensity of the applied DC magnetic field. The current distribution, gas pressure, and electrical power applied to the gas, which changes the plasma density and its cyclotron frequency, are highly adjustable for new operating frequencies. Such characteristics lead to controllability of the radar CROSS SECTION and the SCATTERING pattern of the antenna. In this paper, we investigate the effect of plasma frequency and cyclotron frequency of the plasma antenna on the SCATTERING of radio waves with different incident angles and frequencies.

In this research, the SCATTERING of long-wavelength electromagnetic waves from an elliptical CROSS-SECTION in two different structures and configurations are investigated. The plasma column is exposed to the magnetic field B0.. In the first structure, the plasma column is covered by a dielectric layer, and in the second structure, a dielectric core is coaxial with the plasma column and placed in its center, and the plasma column is covered by a dielectric layer. By solving the equations of continuity, momentum transfer and Poisson's equation, as well as by using the boundary conditions regarding the electric field and potential, we calculate the electric field in different regions. The SCATTERING and radar CROSS SECTION are calculated. The figures related to the resonance frequency , the electric field , the SCATTERING and radar CROSS SECTION are plotted

In this paper, the SCATTERING of long wavelength electromagnetic waves from a warm plasma column with an elliptical CROSS SECTION is investigated. We assume that the incident wavelength is much larger than the CROSS-SECTIONal area of the elliptical column and enter the thermal effects into the calculations using the Boehm-Gross equation. Using suitable boundary conditions, we calculate the electric potential as well as the electric field at the points inside and outside a plasma column with an elliptical CROSS SECTION. Then we obtain the dispersion equation in this case and prove that in the limit state, this equation becomes the dispersion equation in a plasma column with a circular CROSS SECTION. Considering the plasma resonance condition in an elliptical CROSS-SECTION plasma column, we calculate the resonant frequency in this configuration. Finally, we plot the graphs of potential amplitude at the inside and outside points. Note that using the resonant frequency, we can calculate the characteristics of the plasma antenna under study, such as the plasma density.

In this research, the chiral perturbation theory and the mechanism of three-body forces, which are of great importance, are employed through simulations to investigate the chain interaction 𝑝, 𝑑,→,𝐻, 𝑒,, ' →,𝐻, 𝑒,2𝜋,𝜂,→,𝐻, 𝑒,5𝜋,􀬷,􀬷,􀬷,In the following, important parameters such as SCATTERING amplitude ratio, decay rate, and SCATTERING CROSS SECTION of this decay have been calculated. Due to the fact that in nuclear processes, accuracy up to the next to leading order (NLO) can reduce the error rate to a high extent, the calculations performed in this research have been done up to (NLO). The obtained results are highly consistent with the experimental results.

The aim of this investigation was to evaluate the prevalence of dental caries Amongst a group of institationized mentally handicapped children" aged 6 to 12 years. A total of 302 children 173 boys and 129 girls. were encluded for this study who were institutionalized under the city council and Tehran shealth board. candidates were selected in a simple random sampling manager. Results revealed that the mean DMFT of the population of study was at 1.81 for permanent teeth and 1.77 for primary teeth. The mean DMFT of the edlest age group of this population (12 year olds) was 2.76,dearly higher than the mean DMFT of youngest and the whole the rate of the dental caries was found to be higher amongst these handicaps children (65.64%,) when compared to the same age group in normal population.Implementation of a reasonable training program for promoting general knowledge of service providers in relation to oral and dental care including various preventive measures are highly recommended.

In this paper, graphene has been designed for tunable SCATTERING manipulation of a dielectric cylinder. The goal is changing SCATTERING properties of a dielectric cylinder to ones of another cylinder with desired radius. For this purpose, SCATTERING coefficients of the covered and target cylinders have been achieved and equated. Required surface impedance of the graphene in order to obtain the considered goal in the frequencies of 3 and 4 THz has been derived. By properly tuning the chemical potencial of the graphene, caused by induced voltage, this goal has controllably been achieved. Total SCATTERING widths of the bare, target and covered cylinders are obtained from numerical simulations and analytical calculations.

Nobel metal nanoparticles (NPs) are widely used in various applications including optical and biological sensors, biomedicine, photocatalysts, electronics, and photovoltaic cells. The optical properties of gold NPs are surveyed in this paper under the Localized Surface Plasmon Resonance (LSPR) effect, which increases the light absorption and SCATTERING at the LSPR wavelength. This LSPR frequency depends on various factors, including the shape and size of the particles as well as incident electromagnetic polarization. Here, the optical response of gold NPs with different shapes and sizes are investigated using the finite element method (FEM). The results show that the bandwidth, amplitude, and LSPR wavelength depend on the shape and dimensions of the NPs as well as the polarization of the incident light. The LSPR wavelength changes from 500 to 650 nm for different shapes of the gold NPs including sphere, octahedral, cube, ellipsoid, triangle, and with identical volume. To study the NP size effect on the optical properties, the absorption and SCATTERING CROSS-SECTIONs (CSs) are also investigated for different sizes of NPs. The results show a redshift in the LSPR wavelength by increasing the NP size.