Observation of non-symmetric side-scattering during high-intensity laser-plasma interactions

Abstract

Non-symmetric side-scattering has been observed during the interaction between a high-intensity laser pulse and under-dense argon plasma. The angle between the laser’s forward direction and the scattered radiation is found to decrease for increasing electron densities ranging from 0.01 to 0.25 n _c , where n _c is the critical density for the laser wavelength. We show that the observed features of the scattering cannot be described by Raman side-scattering but can be explained to be a consequence of the non-uniform density distribution of the plasma with the scattering angle being oriented along the direction of the resulting electron density gradient.

Keywords

• side-scattering
• Raman scattering
• density-gradient
• near-critical
• density perturbation
• plasma gradient scattering