[en] A method to compute the population density of the resonance and metastable atoms in the Townsend gas discharge has been developed. The method is used to calculate the number of atoms for the dominated mercury excited levels (6³P₀,6³P₁,6³P₂,6¹P₁ and 7³s₁) per ion pair as a function of the ratio E/P₀. The computed mean electron energy and energy distribution function, by solving Boltzmann's equation, as a function of E/P₀ are used. Data confirms that the metastable level 6 ³p₂ is dominating at low E/P₀ (1.e. high pressure discharge) while the resonance level 1p1 is only important at high E/P₀ (1.e. low pressure discharge). The effect of the cumulative ionization and ionization collision between two metastable atoms on the secondary processes is also investigated. A qualitative agreement between the present data and the experimental results of the secondary ionization coefficients is achieved.8 fig

[en] The plasma current sheath dynamic and the ejected plasma from an coaxial accelerator has been studied, in argon gas within the pressure range from 0.4 m bar to 2 m bar using a capacitor bank energies ranging from 1.97 h J to 4.4 kJ. It has been found that the axial plasma current sheath velocity and the azimuthal magnetic field at the back of the sheath depend on the capacitor bank charging voltage and position. The maximum value of the azimuthal magnetic field intensity and axial plasma current sheath are 1.3 kG and 2.9 x 10 ⁶ cm/s respectively, for 12 kV capacitor bank charging voltage. The ejected plasma electron kinetic energy had a maximum value on the axis ≅5.7 x 103 erg/cm³. An energetic electron beam has been detected by x-ray probe with an estimated energy of ≅ 1 KeV. 7 figs

[en] The temporal variation of the emitted line intensity has been investigated, and thus an important information about the dynamic ionization stages in the Z-pinch discharge has been studied. Also the electron temperature Te, has been deduced by using a spectroscopic technique

[en] A plasma focus device has been constructed and tested for producing a high dense plasma. The system was feeded by maximum 3.3 kJ., capacitor bank, which delivers 200KA. With average period 11 μS. The results show that the time at which the first focus starts increases with raising the gas pressure while it was decreased with increasing the charging voltage. The verification of snow-plow model was acheived only at a charging voltage of 14 kV. up wards. (author)

[en] The radial distribution of the electron temperature in a hydrogen plasma generated in a thetatron device is determined by using the line intensity ratio, which has been measured through Abel invertion and a simple computer program. The mean electron temperature is found to be around 10 eV., for H_β, while it is less for Hγ. The obtained profile of the electron temperature is in coincidence with our previous results. (author). 10 refs, 5 figs

[en] The energy distribution function, electron temperature and density in the formed discharge of the DC - magnetron sputtering unit have been determined using different Langmuir probes. The data confirms the deviation of energy distribution function from being Maxwellian. Effects of both magnetic and electric fields on the behavior of the formed plasma are discussed. The experimental data are thus compared with the theoretical predictions. (author). 11 refs, 4 figs

[en] A theoretical model includes the effect of weak shear on the instability of a collisionless, strong magnetized, weakly ionized plasma, has been studied. The experimental results are compared with theoretical predictions of the wave frequency in argon plasma and fair agreement is achieved whenever the magnetic field exceeds certain limit. (author). 11 refs, 4 figs

[en] Transversely excited atmospheric TEA nitrogen laser, 4 nS width and 100 μJ energy, has been used to study the macroscopic behaviour of the plasma sheath generated in a plasma focus device. The shadowgraphic results showed that the plasma is nonhomogeneous and consists of planner sheath accompanied by a group of strips and it moves axially with velocity 6.6 x 10⁶ cm/s while it moves radialy with speed of 1.2x10⁷ cm/s. (orig.)

[en] A hydrogen plasma was produced by a T-type shock tube. Spectroscopic measurements show, the first half cycle produces mainly hydrogen plasma while in the other half cycles the plasma is contaminated with the electrode and wall material. The shock wave produced by the third half cycle has a turbulent behaviour with several peaks of electric and magnetic field. (author)

[en] A fast energy wave packet pulse with a velocity greater than 10⁸ cm/s has been generated from a T-shock tube, accompanying the discharge current disruption and a sharp voltage peak. The distribution of the disrupted wave increases the plasma temperature by 5 eV, and the density jumps to 2-3 times its initial value. The disruption wave streams through the proceeding plasma and shock wave without noticeable dissipative interaction. The production of a backward shock wave has been referred to the destruction of the wave at the expansion chamber. A propagated magnetosonic wave with a velocity of 6x10⁵ cm/s has been detected, which was excited near the discharge electrodes. (orig.)