Simultaneous compression and opacity data from time-series radiography with a Lagrangian marker

Area of Science:

• High-pressure physics
• Materials science
• Shock wave physics

Background:

• Time-resolved radiography is crucial for determining shock Hugoniot states.
• One-dimensional converging shocks allow probing a range of pressures in a single experiment.
• At high pressures, x-ray opacity decreases significantly due to increased temperature.

Purpose of the Study:

• To investigate the use of Lagrangian markers to constrain opacity and Hugoniot states.
• To improve the accuracy of deducing material properties from shock experiments.
• To analyze converging shock waves in polystyrene using this technique.

Main Methods:

• Utilizing time-resolved radiography to measure shock parameters.
• Incorporating Lagrangian markers with known mass.
• Analyzing shock wave propagation and material response.
• Applying the technique to converging shock experiments in polystyrene.

Main Results:

• Lagrangian markers provide additional constraints for opacity and Hugoniot state determination.
• Opacity of shocked material can be uniquely determined under specific conditions.
• Deducing non-assumed properties (equation of state or opacity) is more accurate with marker layers.
• Demonstrated analysis for converging shock waves in polystyrene.

Conclusions:

• Lagrangian markers enhance the accuracy of shock Hugoniot state and opacity measurements.
• The technique is particularly valuable for high-pressure, high-temperature regimes.
• This method offers a more robust approach to material property determination in dynamic experiments.