Author(s) M. A. Abdelati^1*, M. A. Mahmoud², Y. E. E. Gamal¹

Affiliation(s)
¹ National Institute of Laser Enhanced Sciences, Cairo University, El Giza, Egypt.
² Physics Department, Faculty of Science, Sohag University, Sohag, Egypt.

ABSTRACT

We present a theoretical investigation of plasma generation in sodium vapor induced by laser radiation tuned to the first resonance line (3S-3P) at λ = 589 ns. A set of rate equations that describe the rate of change of the ground and excited states population as well as the temporal variation of the electron energy distribution function (EEDF), beside the formed atomic ion Na+, molecular ion  and tri-atomic ions are solved numerically. The calculations are carried out at different laser energy and different sodium atomic vapor densities under the experimental conditions of Tapalian and Smith (1993) to test the existence of the formed tri-atomic ions. The numerical calculations of the electron energy distribution function (EEDF) show that a deviation from the Maxwellian distribution due to the super elastic collisions effect. In addition to the competition between associative ionization (3P-3P), associative ionization (3P-3D) and Molnar-Horn- beck ionization processes for producing , the calculations have also shown that the atomic ions Na+ are formed through the Penning ionization and photoionization processes. These results are found to be consistent with the experimental observations.

KEYWORDS
Plasma, Laser, Collisional Ionization, Association Ionization, Tri-Atomic Ions, Photoionization, Electron Energy Distribution Function

Cite this paper
Abdelati, M. , Mahmoud, M. and Gamal, Y. (2014) Numerical Investigation of the Tri-Atomic Ions Formation during Laser Ionization Based on Resonance Saturation. Journal of Applied Mathematics and Physics, 2, 1123-1129. doi: 10.4236/jamp.2014.212131.

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