Investiycrtion of electron temperature and density of laser-induced-plasma by Langmuir probe up to the centimeters scale distance from the target

Morshedian, Nader; Shahverdi, Fereshteh; Farahbod, Amirhossein

Investiycrtion of electron temperature and density of laser-induced-plasma by Langmuir probe up to the centimeters scale distance from the target

Document Type : Research Paper

Authors

Nader Morshedian

Fereshteh Shahverdi

Amirhossein Farahbod

Abstract

In this paper, electron temperature and ion density of laser-produced plasma in the nanosecond time scale at different ambient gas pressures are studied using single Langmuir probe up to distances of the order of centimeter. The plasma is produced due to the interaction of a focused Nd:YAG laser beam of 30 ns pulse duration with a solid target. Stainless steel rods with 0.35mm diameter are used as Langmuir probe. The reduction rate of the electron temperature and plasma density are estimated within a distance of the order of centimeter. The values of the electron temperature at low pressures of 10-5 up to 10×10-5 mbar are in the range of 2-8eV at the probe distances of order of centimeter. The average value of the ion density is in the order of 1011 cm-3 at the distances 4-6 cm from the target.

Keywords

Laser-produced plasma

Langmuir probe

Electron temperature and donsity

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