High-Energy-Density Astrophysics in the Laboratory
"High-Energy-Density Astrophysics in the Laboratory"
Laboratory astrophysics is the colloquial term for experimental work performed in the lab motivated by astrophysical questions. In general, this type of work complements observational and numerical astronomy; from spectroscopic studies, to astrochemistry, to high energy physics,
and others. It is the high-energy-density (HED) environments, or systems with pressures >1Mbar, that I am interested in exploring. I will discuss a number of HED topics currently being pursued by myself and colleagues at the University of Michigan, as well as fellow scientists and
collaborators at other institutions.
High-power-laser facilities provide an unique opportunity to explore the HED regime in a controlled and diagnosable manner. Much of the infrastructure for these facilities is provided by the inertial confinement fusion (ICF) program being pursued around the world. I will
touch briefly on the basics of ICF and demonstrate how this leads directly to the use of these facilities for basic plasma nuclear science. As stellar energy is created in HED plasma, the controlled study of these nuclear reaction can lead to a better understanding of the system as a whole.
These laboratory systems can be directly scalable to a specific astrophysical object when specific similarity conditions hold. I will discuss the theory behind these criteria and provide a well-scaled experiment that investigated Rayleigh-Taylor growth in core-collapse supernovae. Much work goes into developing this kind of platform, where a well-scaled experiment may be performed with respect to a specific object of interest. In many cases, however, direct scaling is not possible. Rather, achievement of specific dimensionless parameters in the lab is required to reach a relevant physics regime and measurements of these systems may be used as benchmarks for astrophysical codes. I will discuss a number of experimental platforms currently under development to investigate: the formation of collisionless shocks and the role of self-generated magnetic fields, the dynamics and evolution of supersonic magnetized jets, and the production of relativistic electron-positron jets.