Accession Number:

AD1021274

Title:

Shack-Hartmann Electron Densitometer (SHED): An Optical System for Diagnosing Free Electron Density in Laser-Produced Plasmas

Descriptive Note:

Technical Report,03 Jan 2013,30 Apr 2014

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD ABERDEEN PROVING GROUND United States

Personal Author(s):

• Valenzuela,Anthony R.

Report Date:

2016-11-01

Pagination or Media Count:

26.0

Abstract:

The Shack-Hartmann Electron Densitometer is a novel method to diagnose ultrashort pulse laser produced plasmas by measuring the phase change to a probe laser beam. Free electrons in a plasma cause distortions to the phasefront of a probe laser that is measured through a lenslet array onto a camera. This method allows for superior performance in measuring minute variations in the electron density in 2 dimensions with sub picosecond time resolution. The data taken demonstrated the ability to diagnose plasmas with densities of the order of 1019 cm-3 and show the temporal evolution of the plasma long after the driving laser pulse has left. The method can be further improved by enclosing the probe beam and adding a second axis to allow for tomographic reconstruction of the electron density in 3 dimensions.

Descriptors:

• free electrons
• Laser produced plasmas
• ELECTRON DENSITY

Subject Categories:

• Plasma Physics and Magnetohydrodynamics
• Nuclear Physics and Elementary Particle Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE