Another Step for High-Energy-Density Science and Teller’s Legacy
THIS January, we begin a journey that will trace and celebrate the intellectual contributions of one of Lawrence Livermore’s founders—Edward Teller. January 15, 2008, is the centennial of Teller’s birth. Between now and then, we will examine the accomplishments of this man who, along with Ernest O. Lawrence and Herbert York, established in 1952 the institution now known as Lawrence Livermore National Laboratory.
Teller’s scientific legacy is distinguished by an unusual blend of abstract inquiry and innovative application over three-quarters of a century. His scientific career began as the quantum physics revolution opened vast areas to detailed understanding. In later years, Teller’s interest in nuclear fusion and matter at high energy density (HED) meshed naturally with his role in national defense. This enduring interest in high-energy-density science, which is key to mastery of fission and fusion science and its applications, provides the starting point for our journey.
HED science is the study of matter under extreme conditions, such as those found in the center of a star or the implosion of a nuclear weapon. The exploration of matter at HED has been a Laboratory hallmark since its founding. HED science is a critical component of Lawrence Livermore’s mission responsibilities and a key strategic component of the Laboratory’s future. The National Science and Technology Council identified HED science as one of seven theme areas at the intersection of physics and astronomy that are ripe for investment and show great promise.
As described in the article Titan Leads the Way in Laser–Matter Science, Livermore has taken another major step in helping to meet this promise. In commissioning the Titan petawatt-class laser at the Jupiter Laser Facility, the Laboratory enhanced its leadership in HED science and continues its legacy of using advanced lasers to explore this field. Titan joins other Livermore laser platforms including the Janus, Callisto, Europa, and COMET lasers and associated target chambers. Titan is one of only three petawatt-class lasers worldwide and currently is the only one offering synchronized short- and long-pulse operation.
Titan’s mission is to support research pertinent to Laboratory programs, to promote collaborations with research institutions and universities, and to provide a stimulating environment for training young scientists. The National Nuclear Security Administration, the Department of Energy’s Office of Science, and the Laboratory Directed Research and Development Program all sponsor work at the facility. With Titan and the other Livermore lasers, scientists are pursuing mission-based science with HED research activities
to study laser–plasma interactions, fast ignition, high-pressure material science, opacity, x-ray lasers, and warm dense matter.
Titan, with both short-pulse (subpicoseconds to a few picoseconds) and long-pulse (typically nanoseconds) capabilities was completed in the summer of 2006. In September, the Jupiter Laser Facility Academic Use Program was the first to simultaneously use Titan’s long- and short-pulse laser beams in experiments facilitated by the Institute for Laser Science and Applications (ILSA).
The ILSA academic team comprised faculty, postdoctoral researchers, and graduate students from the University of California at San Diego, Ohio State University, and the University of Rochester working with researchers from the Laboratory’s Physics and Advanced Technologies and National Ignition Facility (NIF) Programs directorates. Many of the academic participants are university researchers associated with the Fusion Science Center for Extreme States of Matter, which is centered at the University of Rochester and funded by the Office of Science’s Fusion Energy Sciences Program, or graduate students who are supported through ILSA’s participation in the Laboratory’s University Education Partnerships Program. The collaborative experiments included measuring hot-electron transport in compressed, shocked foams.
The value of Titan and the Jupiter Laser Facility will continue to grow as NIF—the ultimate HED user facility—begins full operation. Titan will remain crucial for developing diagnostics and targets for NIF, and Titan experiments will help advance the understanding of issues facing fast ignition for inertial confinement fusion energy. Many Titan experiments will explore new concepts—some of which will undoubtedly emerge from NIF HED experiments—and serve as a test bed for more complex tests using NIF. Titan also will help train the cadre of young scientists who will use NIF over the next 20 to 30 years.
True to Teller’s legacy of applying physics to solve problems of national importance, HED experiments with high-energy, short-pulse lasers promises to lead to new discoveries and applications, some of which are poised to become reality and others which are as yet only imagined.