Experimental and radiation-hydrodynamics modeling studies of warm dense matter at the Texas Petawatt Laser

We present experimental and simulation studies of warm dense matter produced by isochoric heating at the Texas Petawatt Laser Facility. Experimental studies of warm dense matter can provide measurements of equation of state, thermal conductivity, and other physical quantities, with the goal of more accurate modeling. This work presents results of experiments at the Texas Petawatt laser in which aluminum foils and carbon foams are isochorically heated with a laser-accelerated proton beam, as well as radiation-hydrodynamics simulations of the heated targets. The brightness temperature over time of the heated target is measured by a streaked optical pyrometer. We have observed peak brightness temperatures from 1-10eV.

We model the cooling and expansion of the heated target in xRAGE, an Eulerian radiation-hydrodynamics code. We present our xRAGE modeling results for both solid aluminum targets and CRF (carbon) foam targets, showing that foam appears to cool slowly on the pyrometer due to partial transparency. In order to properly process simulations of cooling foam, accounting for optical depth in a photosphere calculation is necessary.