Observation of overdense infrared scattering from a post pinch plasma focus

Results of a collective CO2 laser scattering experiment performed on a dense plasma focus are reported. Scattering measurements were made at two incident beam polarizations both along the axis and transverse to the axis of a plasma focus in the pinch and post-pinch phases, and were combined with X-ray and neutron observations. Overdense scattering was observed in the post-pinch plasma and found to be spatially correlated with bright X-ray emitting regions detected by soft X-ray pinhole photographs. Underdense collective scattering was not observed, indicating that high-level turbulence is not present in the focus in the plasma frequency and wave vector domain measured, and suggesting that any localized turbulence may only be indirectly related to ion heating.