Multi-University Center of Excellence for Pulsed-Power-Driven High-Energy Density Science: Mission

The mission of the Center is to carry out world class experimental, theoretical, and computational high energy density laboratory plasma (HEDLP) physics research, through fundamental studies and applications of magnetized high energy density (HED) plasmas produced by pulsed power machines, and to train the next generation of HEDLP research scientists. The Center of Excellence carries out experiments in a variety of configurations, all of which are current-driven, hot, dense plasmas that fit within the general name “dense Z-pinches.” The experiments are supported by computer simulations and theoretical modeling in order to help achieve an understanding of the experimental results and to help validate the computer simulations and theoretical models.

The principal objective of our research center is now and will continue to be to improve our understanding of the physics of HED plasma through high quality experimental research, computer simulations, and theory. In the process, our goals include advancing the capability of HED science in the United States, and contributing substantially to the training of the next generation of HED research scientists for stockpile stewardship and other programs of importance to national security. Other goals include contributing to the application of magnetized HED plasmas to inertial fusion energy and intense radiation generation, and to the understanding of observed high energy astrophysical phenomena.

In order to achieve these objectives in the large, we operate two pulsed power machines with state-of-the-art suites of diagnostics. With these machines, our graduate students at Cornell design and carry out world class magnetized HED plasma experimental research. They also develop advanced computer simulation and analytic theory tools to help understand the experiments. Where necessary, we develop our own diagnostic tools, including visible and X-ray spectroscopic and imaging devices. Although the bulk of this effort is now and will continue to be carried out at Cornell, where appropriate, we collaborate with other HED researchers: from elsewhere in the United States, to enhance in-house capability; and from outside the United States, to enhance US scientific infrastructure by familiarizing ourselves and our students with world-class research capability that has been developed in foreign research laboratories.

Previous awards names – Center for Pulsed-Power-Driven High-Energy-Density Plasmas 2012- 2017 and Center for the Study of Pulsed Power Driven High Energy Density Plasmas 2002-2013

University of California San Diego

Dr Bott-Suzuki’s group at UC San Diego develops experimental platforms to study shock formation in plasma flows, and current distribution in coaxial electrode geometries. Primary activities center around the role of radiation in the development of shock profiles in high density flows, and determination of the compressibility of the plasma flow across the shock. These studies use both the XP and COBRA generators and with novel diagnostic developments and load geometries to acquire new data on such phenomenon. One aim is to begin a database on the compressibility of plasmas in regimes relevant to the high energy density regime, through analysis of the full range of experiments carried out by the Center.

Imperial College of Science Technology and Medicine

I am one of key researchers at Imperial College London, and have collaborated with the Centre since it was originally formed. Working with my colleagues Prof. Sergey Lebedev and Prof. Jeremy Chittenden, the team at Imperial use COBRA’S sister machine, the MAGPIE pulsed power facility, to perform a variety of High Energy Density Physics experiments and simulate these using the massively parallel Gorgon RMHD code. In particular, we are exploring the dynamics of Radiative Shockwaves, such as those seen in Astrophysics, and methods to create the high magnetic fields required for the MAGLIF fusion scheme. We are also developing cutting edge diagnostics including time resolved XUV emission and absorption spectrometry.

P. N. Lebedev Physical Institute of the Russian Academy of Sciences

Development and testing new diagnostics of High Energy Density Matter based on XUV and X-ray imaging and spectroscopy. Studying of nanosecond explosion of wires and foils using optical, XUV and X-ray diagnostics. Development of extremely bright sources of XUV and X-ray radiation based on X-pinches, exploding wires, foils and surface discharges.

The Weizmann Institute of Science

One of the most central problems in HED physics is the determination of the ion temperature (Ti), as many physical processes, particularly fusion reactivity, are temperature-sensitive. At the same time, the determination of Ti and its discrimination from non-thermal motion is extremely difficult, because Doppler-broadened line shapes can be due to either thermal or non-thermal motions. The determination of the non-thermal motion is crucial by itself, since it is an energy stored in the plasma that contributes neither to radiation nor to fusion, unless this energy can be converted quickly into ion temperature. Thus, distinguishing between energy placed in hydrodynamic motion from thermalization of the ions is of paramount importance to advance HED physics. The WIS Laboratory has made a seminal contribution by developing and implementing methods that enable the discrimination between these two motions [ , , ]. Here, we plan to extensively apply these experimental methods in various systems at WIS, Cornell, and at the other participant laboratories.

Princeton University

Motivated by remarkable observations at the Weizmann Institute [1-4], where substantial, non-radial, hydrodynamic motion, thought to be turbulent kinetic energy (TKE) was deduced in gas puff Z-pinch experiments, we discovered a sudden viscous dissipation effect [5]. This effect arises when TKE, amplified by compression, is then rapidly dissipated into temperature by viscosity. Since the viscosity in plasma, as opposed to neutral gases, is very sensitive to temperature (~T5/2), once the TKE begins to dissipate into heat, the temperature rises, increasing the viscosity, which further increases the temperature. This is an explosive instability, until the TKE is converted to temperature.

University of Michigan

At the University of Michigan, we will be conducting experiments in the Plasma, Pulsed Power, and Microwave Laboratory using a pulsed-power machine called MAIZE (Michigan Accelerator for Inductive Z-pinch Experiments). This generator produces an electrical current pulse that rises from 0 to 1 million amperes in about 100 nanoseconds. The magnetic pressure associated with this pulse is used to compress matter, usually in the plasma state. These experiments will be used to study plasma instabilities that occur during compression. In some cases, these experiments will be used to generate x-rays and neutrons. We will also develop new diagnostic instrumentation to better measure the plasma properties and magnetic fields produced in these experiments. To enhance overall Center capabilities and results, the facilities at UM will be available for collaboration with other Center participants.

University of New Mexico

The University of New Mexico (UNM) will contribute to the proposed center of excellence in three technical areas. First, we will develop, deploy and operate an infrared coherent Thomson scattering diagnostic suitable for studying fluctuations and turbulence on the COBRA accelerator. Second, we will conduct complimentary HED-relevant experiments at lower densities, but larger spatial scales, using a compact coaxial plasma gun and background magnetized plasma in the HelCat basic plasma science device [ref1] at UNM. Third, we will pursue the conceptual development of a metal vapor plasma source relevant to HED conditions.