From National Ignition Facility at Lawrence Livermore National Laboratory: “NIF sets new laser energy record”

From National Ignition Facility at Lawrence Livermore National Laboratory


July 10, 2018

Breanna Bishop

LLNL NIF target chamber

NIF’s target chamber is where the magic happens — temperatures of 100 million degrees and pressures extreme enough to compress the target to densities up to 100 times that of lead are created there. Photo by Jason Laurea/LLNL

Lawrence Livermore National Laboratory’s (LLNL) National Ignition Facility (NIF) laser system has set a new record, firing 2.15 megajoules (MJ) of energy to its target chamber — a 15 percent improvement over NIF’s design specification of 1.8 MJ, and more than 10 percent higher than the previous 1.9 MJ energy record set in March 2012.

This demonstration shot successfully meets a National Nuclear Security Administration (NNSA) Level 2 milestone for 2018. NIF, the world’s largest and most energetic laser, is funded by NNSA to serve as a critical research facility supporting the U.S science-based Stockpile Stewardship Program (SSP).

“NIF’s users are always asking to use more energy in their experiments, because higher energies enhance the science NIF can deliver in support of the stewardship program. These results mark a major step toward increasing NIF’s energy and power capability,” said NIF Director Mark Herrmann. “This demonstration serves as the first step on a path that could allow NIF to operate at substantially higher energies than ever envisioned during NIF’s design.”

The purpose of this experiment was to demonstrate the highest energy NIF can safely deliver with its current optics and laser configuration. Increasing NIF’s energy limit will expand the parameter space for stewardship experiments and provide a significant boost to the pursuit of ignition — a key element of NNSA’s Stockpile Stewardship Program.

This work builds on a successful demo laser campaign performed on NIF last year, which utilized just four of NIF’s beams to study the performance limits of the NIF laser. Recently published in Nuclear Fusion, the experimental campaign was designed to assess laser performance limits and operational costs against predictive models. The campaign culminated in the delivery of the highest energies to date and informed the effort to demonstrate 2.1 MJ on the entire 192-beam laser system.

“The successful 2.1 MJ demonstration is the result of a sustained science and technology investment in NIF and fundamental understanding of optical damage, much of which has been supported by Laboratory Directed Research & Development (LDRD) and other institutional programs,” said NIF & Photon Science Principal Associate Director Jeff Wisoff.

The NIF laser uses tens of thousands of large precision optical components, including lenses, laser glass slabs, mirrors and frequency conversion crystals to amplify and guide 192 laser beams to a small target in the 10-meter target chamber. Continuous research and development efforts have put these optics at the cutting edge of material science and technology and play a crucial role in raising the laser’s energy and power thresholds. Recent breakthroughs have reduced the level of damage initiation and growth in the optics and led to a reduced cost to mitigate existing damage spots.

Based on this successful demonstration, NIF is working with LLNL’s ignition program to execute the first ignition experiments that utilize this enhanced energy capability later this summer. Looking ahead, this is the first major step toward extending NIF’s energy and power output through technology development and laser research to extend the NIF mission space and its contributions to the SSP.

See the full article here .


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The National Ignition Facility, or NIF, is a large laser-based inertial confinement fusion (ICF) research device, located at the Lawrence Livermore National Laboratory in Livermore, California. NIF uses lasers to heat and compress a small amount of hydrogen fuel with the goal of inducing nuclear fusion reactions. NIF’s mission is to achieve fusion ignition with high energy gain, and to support nuclear weapon maintenance and design by studying the behavior of matter under the conditions found within nuclear weapons. NIF is the largest and most energetic ICF device built to date, and the largest laser in the world.

Construction on the NIF began in 1997 but management problems and technical delays slowed progress into the early 2000s. Progress after 2000 was smoother, but compared to initial estimates, NIF was completed five years behind schedule and was almost four times more expensive than originally budgeted. Construction was certified complete on 31 March 2009 by the U.S. Department of Energy, and a dedication ceremony took place on 29 May 2009. The first large-scale laser target experiments were performed in June 2009 and the first “integrated ignition experiments” (which tested the laser’s power) were declared completed in October 2010.

Bringing the system to its full potential was a lengthy process that was carried out from 2009 to 2012. During this period a number of experiments were worked into the process under the National Ignition Campaign, with the goal of reaching ignition just after the laser reached full power, some time in the second half of 2012. The Campaign officially ended in September 2012, at about 1⁄10 the conditions needed for ignition. Experiments since then have pushed this closer to 1⁄3, but considerable theoretical and practical work is required if the system is ever to reach ignition. Since 2012, NIF has been used primarily for materials science and weapons research.

National Igniton Facility- NIF at LLNL

The preamplifiers of the National Ignition Facility are the first step in increasing the energy of laser beams as they make their way toward the target chamber

Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.

LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.

Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security Administration

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