الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Using the Hartree- Fock- relativistic method, introduced by Cowan, the radial wave function parameters for neutral Gallium and its isoelectronic sequence, have been determined. These parameters have been used to calculate energy levels, oscillator strength, wavelength and life time by using Cowan code. Since both experimental and theoretical data for all ions were available except for some energy levels belonging to the ions Ga(I) up to Rh(XV), we were able to make correlations to individual levels by adjusting the diagonal elements of the Hamiltonian matrix. The unpublished energies were extracted from the nuclear charge-expansion theory.
For first part of our results we have found that the excitation energy increases as the atomic number, Z, increases and as well as the degree of ionization increase. It is noticeable to say that our discussion of the results and the outcome of the comparisons with NIST increase our confidence in the accuracy of the present data set.
In the second part of this study, collision pumped population inversions occur for several transitions in the Gallium-isoelectronic sequence. At the same time, over a limited range of atomic number Z, electron density, and electron temperature, we have found that:
• At low densities the reduced populations increase as functions of electron density. This is due to the increase in the collisional excitation rates with density.
• At high electron density, where the collisional excitation rates exceed the radaitive decay rates, the reduced populations are independent of electron density and are approximately equal.
• The population inversion is largest where the electron collisional de-excitation rate for the upper level is comparable to the radiative decay rate for this level. For increasing atomic number Z, the population inversions occur at higher electron densities. This is due to the increase in the radiative decay rat with Z and the decrease in the collisional de-excitation rat coefficient with Z.
• The calculated gain coefficients for various transitions show large values when the electron collisional de-excitation rate for the upper level is comparable to the radiative decay rate for this level.
At the end of this section it should be pointed out that we have publishd the following research:
”Atomic Data and Laser Transitions in As- like Gallium”, in American Journal of Physics and Applications (AJPA).
In addition we have sent”Laser Transition in Ru- like gallium”,to
publishe in Canadian Journal.