High Energy Density Physics (HEDP) is a branch of physics that has received tremendous interest over the past several years within the academic community and national laboratories. HEDP refers to physics that deals with matter which is both very hot and very dense. This definition covers a broad range of scientific disciplines from astrophysics, fusion energy, planetary science, and certain areas of material science. Historically, creating high energy density conditions in a laboratory has been difficult since it requires heating materials to temperatures of millions of Kelvin and compressing materials to many times their solid densities. However, new experimental facilities, such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, are now able to produce HEDP conditions in a laboratory. Understandably, there is enormous interest within the scientific community in using these new facilities to make exciting, new discoveries.
While it is now possible to create HEDP conditions in a laboratory, experiments are still extremely expensive to perform and challenging to diagnose. Computer simulations are used to overcome these obstacles. However, the simulation codes themselves are very complex, requiring both enormous computational power and an impressive range of physical models.
An effort, jointly funded by DOE NNSA and ASCR, has been ongoing to add capabilities to FLASH to make it an open, highly capable toolset for the academic HEDP community. The FLASH code can be used to simulate HEDP experiments for planning and analysis purposes. As a result of this effort, FLASH now contains many of the capabilities needed for performing HEDP experiments, including state-of-the-art Eulerian Hydrodynamics and MHD solvers, flux-limited multigroup radiative transfer, laser energy deposition, and thermal conduction. The code is now being used by institutions around the world to simulate HEDP experiments.
The universe is filled with magnetic fields which vary greatly in strength. The mechanism that produced these fields and the manner in which they have been amplified over time is not fully understood. One potential explanation is that these fields were generated by asymmetric shock waves then amplified over time by turbulence. Gianluca Gregori and his team from the University of Oxford are leading an effort to use laser driven HEDP experiments to better to understand how asymmetric shock waves can produce magnetic fields in plasmas. The Flash Center is performing simulations of these experiments using the magnetohydrodynamic capabilities of the FLASH code. To support this effort, the center has been awarded 40 million hours of computing time on the Intrepid and Mira supercomputers at Argonne National Laboratory as part of the DOE Office of Science INCITE program. These simulations will help design experiments on a number of laser facilities and will be used to better understand results from prior experiments.
Here are some external sites that are relevant to the Flash Center HEDP effort. If you have any suggestions for more sites, email us at firstname.lastname@example.org. Please note that the Flash Center for Computational Science is not responsible for the content of the sites linked from this page.