Transport in Ultra-Dense Plasmas Produced by a Picosecond Laser Pulse
Abstract
This report presents recent experimental results obtained with the Table Top Terawatt laser at the Ultrafast Science Laboratory (University of Michigan). Interaction of the picosecond laser pulse with an overdense plasma was investigated with spectroscopic observations in the XUV range using a compact 1 m grazing incidence spectrograph. The emission from laser-irradiated targets made of silicon wafers coated with aluminum layers of variable thicknesses (from 100 to 5000A) was recorded to allow spectral line intensity measurements from silicon and aluminum L-shell ions. The experiment was conducted using laser irradiation at both wavelengths lambda L = 1.06 or 0.53 um. The laser energy penetration depths were derived from the variation of the XUV spectral intensities with the different layer thicknesses. The values obtained cover the range 300-700 A at lambda L = 1.06 um and 250-400 A at lambda L = 0.53 um. The smaller penetration depth determined at the laser doubled frequency corroborates earlier x-ray results in the keV range at the same laboratory. The penetration depths derived provide a better understanding of the electron heat transport phenomena, supporting in particular the assumption of thermal condition in an overdense plasma.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 06, 1992
- Accession Number
- ADA247827
Entities
People
- D. A. Newman
- G. Mehlman
- P. G. Burkhalter
Organizations
- United States Naval Research Laboratory