WHAT DID THE 2011 EARLY CAREER AWARD ALLOW YOU TO DO?

My DOE Early Career Award was important both as a recognition of my prior scientific contributions and as a resource to enable future achievements.

I was privileged to join Sandia National Laboratories just as it had completed a major laser facility (Z-Beamlet) adjacent to the Z machine, the world’s largest pulsed power accelerator. Prior to the award, I made a name for myself by using the laser to take X-ray movies of the powerful z-pinch X-ray sources we were creating on Z. As the award began, we were making bold and exciting claims about what might be possible in novel radiation and fusion target designs, but there was a lot of uncertainty in our ability to simulate z-pinch implosions. We needed quantitative data on the implosions to have confidence that our target ideas were worthy of additional investments.

A major theme of my early career was creating the first platforms and images on the Z machine that could be used to benchmark our computational models. I just wrote a paper along these lines when I submitted the award proposal, and the award enabled me to spend another five years doing increasingly sophisticated work in this area.

Another way in which the award was important was that it established my credibility as a scientific leader within the fusion and high energy density physics communities. This ultimately led to me to shift my career into scientific management. Today, I am the Director of the Pulsed Power Sciences Center at Sandia, responsible for stewarding all of the scientific research on the Z machine (and more). The award helped me feel more confident in my ability to nurture the talent and direct the work of the many other exceptional scientists in my organization.

Today I look forward to mentoring future talent within the DOE and ensuring that the next generation of scientists continues to provide exceptional service in the national interest.

ABOUT:

Daniel Sinars is the Director for the Pulsed Power Sciences Center and the Sandia Executive for the Inertial Confinement Fusion and Science programs of the National Nuclear Security Administration.

SUPPORTING THE DOE SC MISSION:

The Early Career Research Program provides financial support that is foundational to early career investigators, enabling them to define and direct independent research in areas important to DOE missions. The development of outstanding scientists and research leaders is of paramount importance to the Department of Energy Office of Science. By investing in the next generation of researchers, the Office of Science champions lifelong careers in discovery science.

For more information, please go to the Early Career Research Program.

THE 2011 PROJECT ABSTRACT:

Fundamental Instability Measurements in Magnetically Driven Z‐Pinch Liner Implosions

The magnetic pressure generated by large, pulsed currents can be used to directly compress initially solid metal tubes (liners) to extreme conditions. The Sandia Z facility can generate 100 megabars of magnetic pressure (25 MA at a radius of 1 mm), similar to the radiation‐driven ablation pressure on fusion capsules designed for the National Ignition Facility.   

Achieving extreme conditions in the laboratory for fusion or dynamic materials studies requires the compression of matter and current to small radii. The most important factor limiting the controlled compression of dense matter to small radii using magnetic pressure is the magneto‐Rayleigh‐Taylor (MRT) instability. In liner implosions the MRT instability arises at the outer plasma‐vacuum interface, where the driving magnetic pressure plays a role analogous to a light fluid pushing on a heavy fluid (the plasma liner) as in the classical fluid Rayleigh‐ Taylor instability. The MRT instabilities in fast z‐pinch systems are complex, and we rely heavily on advanced simulation tools to model them. Surprisingly, there are few data that can be used to validate these simulation tools, particularly in the ~100 ns regime where plasma effects and strong shocks can be important. The principal investigator recently led the first well‐characterized MRT growth measurements on ~100 ns time scales using initially solid Al liners.

This research will enable several additional experimental campaigns on the Sandia Z facility to study both fundamental and applied aspects of the MRT instability. Data collected in these experiments are expected to ultimately improve our physics understanding and help us validate critical simulation tools, thereby benefiting fusion and dynamic materials applications based on magnetic pressure drive.

RESOURCES:

D.B. Sinars, M.A. Sweeney, C.S. Alexander, et al., “Review of pulsed power-driven high energy density physics research on Z at Sandia.” Physics of Plasmas 27, 070501 (2020). [DOI: 10.1063/5.0007476

D.B. Sinars, S.A. Slutz, M.C. Herrmann, et al., “Measurements of magneto-Rayleigh-Taylor instability growth during the implosion of initially solid Al tubes driven by the 20-MA, 100-ns Z facility.” Phys. Rev. Lett. 105, 185001 (2010). [DOI:10.1103/PhysRevLett.105.185001]

D.B. Sinars, M.E. Cuneo, E.P. Yu, D.E. Bliss, T.J. Nash, J.L. Porter, C. Deeney, M.G. Mazarakis, G.S. Sarkisov, and D.F. Wenger, “Mass profile and instability growth measurements for 300-wire z-pinch implosions driven by 14-18 MA.” Phys. Rev. Lett. 93, 145002 (2004). [DOI: 10.1103/PhysRevLett.93.145002]

 

Additional profiles of the Early Career Research Program award recipients can be found on the Early Career Program Page.

The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit www.energy.gov/science.