NNSA Administrator D'Agustino Testifies Before Key House Panel on Nuclear Posture Review

Earlier today on Capitol Hill, the Administrator of the National Nuclear Security Administration (NNSA), Thomas D’Agostino, described NNSA’s key role in implementing the administration's nuclear security agenda during a hearing before the U.S. House of Representatives' Committee on Armed Services. Administrator D'Agostino was joined on the committee's  witness panel by Gen. Kevin P. Chilton of the U.S. Strategic Command, Under Secretary of State Ellen O. Tauscher and Principal Deputy Under Secretary of Defense James N. Miller.

In his first Congressional testimony since the release of the 2010 Nuclear Posture Review, Administrator D’Agostino took the opporutnity to highlight the critical role that the NNSA and its laboratories and production sites play in enhancing our nation’s nuclear security.

In his prepared remarks the D'Agostino called the NPR “an important step toward ending Cold War thinking and adopting a 21st century approach to nuclear weapons and a broader array of nuclear security issues.” In addition to supporting the recapitalization of NNSA’s physical infrastructure, the NPR also recognized the importance of revitalizing human capital across the nuclear security enterprise. Those investments support the full range of NNSA’s nuclear security missions.

Administrator D’Agostino also highlighted the joint statement on the NPR and NNSA’s life extension programs issued last week by the directors of NNSA’s three national security laboratories. In their statement, the Directors said that approach, which excludes further nuclear testing and includes the consideration of the full range of life extension options, “provides the necessary technical flexibility to manage the nuclear stockpile into the future.”

The following are excerpts of Administrator D’Agostino’s opening remarks as prepared for delivery. The full text can be found here:

• ADOPTING A 21ST CENTURY APPROACH TO NUCLEAR SECURITY: “This Nuclear Posture Review is an important step toward ending Cold War thinking and adopting a 21st century approach to nuclear weapons and a broader array of nuclear security issues. This path forward will require a long-term commitment from the Congress to provide the support and the resources necessary to sustain our nuclear deterrent and enable future arms reductions.”

• RECAPITALIZING THE NNSA INFRASTRUCTURE: “The NPR also concluded that the NNSA needed to recapitalize the aging infrastructure and to renew our human capital -- the critical cadre of scientific, technical, and engineering experts who carry out our stockpile management work and support our other missions.”

• FUNDING UPF AND CMRR: “NNSA will also fund two key facility projects: the Chemistry and Metallurgy Research Replacement Project at Los Alamos National Laboratory to replace the existing 50-year old Chemistry and Metallurgy Research facility by 2021; and a new Uranium Processing Facility at the Y-12 Plant in Oak Ridge, Tennessee to come on line for production operations by 2021.”

• REVITALIZING NNSA’S HUMAN CAPITAL: “Responsible stockpile management requires not only the supporting infrastructure, but also a highly capable workforce with the specialized skills needed to sustain the nuclear deterrent and to support the President’s nuclear security agenda. The NPR noted the importance of recruiting and retaining the ‘human capital’ needed in NNSA for the nuclear security mission.”

• STATEMENT FROM THE LAB DIRECTORS: “I want to share with the Committee a statement from our National Laboratory Directors that provides their views on the NPR. The Directors universally state that: ‘We believe that the approach outlined in the NPR, which excludes further nuclear testing and includes the consideration of the full range of life extension options …. provides the necessary technical flexibility to manage the nuclear stockpile into the future with an acceptable level of risk.’”

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National Nuclear Security Lab Directors Issue Joint Statement on Nuclear Posture Review

The directors of the three National Nuclear Security Administration Laboratories operating under the U.S. Department of Energy– Dr. George Miller from Lawrence Livermore National Laboratory, Dr. Michael Anastasio from Los Alamos National Laboratory and Dr. Tom Hunter from Sandia National Laboratories – today issued a statement Late last Friday commenting on the Nuclear Posture Review. Their joint statement reads as follows: 

“A key responsibility of the three Department of Energy, National Nuclear Security Administration Laboratories–Lawrence Livermore National Laboratory, Los Alamos National Laboratory and Sandia National Laboratories–is to provide technical underpinnings that ensure the safety, security, and effectiveness of the United States’ nuclear deterrent. The recently released Nuclear Posture Review (NPR) provides the Administration’s policy framework and path forward for ensuring that ‘the nation’s nuclear weapons remain safe, secure and effective.’

“We believe that the approach outlined in the NPR, which excludes further nuclear testing and includes the consideration of the full range of life extension options (refurbishment of existing warheads, reuse of nuclear components from different warheads and replacement of nuclear components based on previously tested designs), provides the necessary technical flexibility to manage the nuclear stockpile into the future with an acceptable level of risk.  We are reassured that a key component of the NPR is the recognition of the importance of supporting ‘a modern physical infrastructure -comprised of the national security laboratories and a complex of supporting facilities–and a highly capable workforce with the specialized skills needed to sustain the nuclear deterrent.’”

NREL Work Ensures LED's Have a Bright Future

Light bulbs that last 100 years and fill rooms with brilliant ambiance may become a reality sooner rather than later, thanks to a recent discovery made by scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL).

It seems that NREL scientists have found a way to generate a tricky combination of green and red that may just prove to be the biggest boost for illumination since Edison's light bulb. Green isn't just a symbol of environmentalism, it is a real color, and a desperately needed one for researchers looking for a way to light homes, streets and buildings at a fraction of today's costs.

LEDs — light-emitting diodes — are the promise of the future because unlike tungsten bulbs or compact fluorescent bulbs, they deliver most of their energy as light, rather than heat. An extra plus is that they don't contain dangerous mercury.

The era of LEDs is fast approaching. The U.S. Department of Energy expects to phase out tungsten bulbs in four years and compact-fluorescents in 10 years. That will leave LEDs with virtually 100 percent of the market.

To make an LED that appears white, researchers minimally need the colors red, green and blue. The white light from the sun is really all the colors of the rainbow. Without at least red, blue and green from the spectrum, no lighting device will be practical for home or office use. Red proved easy to generate, and about 15 years ago, Japanese scientists found a way to generate blue, thus providing two of the key colors from the spectrum of white light.

But green has been elusive. In fact, the $10 LEDs that people can buy now are made to look white by aiming the blue light at a phosphor, which then emits green. It works OK, but the clunky process saps a big chunk of the efficiency from the light.

Along came NREL, a world leader in designing solar cells, but a neophyte in the lighting realm.

NREL scientist Angelo Mascarenhas, who holds patents in solar-cell technology, realized that an LED is just the reverse of a solar cell. One takes electricity and turns it into light; the other takes sunlight and turns it into electricity.

"We'd been working with solar cells for 30 years," Mascarenhas said. "Could we find some device where we could just reverse the process of making solar cells?"

Indeed, Mascarenhas found it. NREL had won major scientific awards with its inverted metamorphic solar cells, in which the cells are built by combining layers of different lattice sizes to optimally capture solar energy. In fact, an NREL-produced IMM cell set a world record by converting 40 percent of absorbed sunlight into electricity.

Along the way, "We had already developed some of the know-how to capture sunlight in this green spectral region," Mascarenhas said. They hadn't reached there, because solar cells don't need a green, but they had begun to understand the challenges of getting to a green.

For a decade, LED researchers had tried and failed to make a reliable efficient green light by putting indium into gallium nitride.

"All signs indicated an impasse," Mascarenhas said. "When you come across an impasse, you don't just bang your head against the wall. You end up breaking your head, not the wall. Instead, you move away from the wall, you find a different path."

He and his fellow solar-cell researchers had dealt with the same problem trying to build a solar cell with gallium indium phosphide. When the lattices created by molecular gases don't match up with the lattices of the layer below, "It can't grow well and the efficiency is very, very poor," Mascarenhas said.

NREL's solar cell experts found a way around that. They put in some extra layers that gradually bridge the gap between the mismatched lattices of the cell layers.

"The approach is to grow a different material with an in-between lattice," Mascarenhas said.

The researchers deposited layers that had lattice patterns of atoms close to, but not exactly matching, the layers below. The tiny gap in size was at the so-called "elastic limit" of the material — close enough that the lattices bonded to each other and impurities were deflected away. Then, add a third layer, this one again at the precise "elastic limit" of the one below. After about seven microns of layering, the result is a solar cell with a firm bond and almost no impurities.

Why not try that same process, only in reverse, to make a reliable deep-green LED using indium gallium phosphide?

Astonishingly, once the concept was understood, Mascarenhas's team produced a radiant deep green on their very first try — without any money backing the effort.

The aim now is to provide a fourth color to make that white light even whiter.

NREL plans to use a slightly deeper red and a lemony green, which would then be combined with a blue and a very deep green made using the gallium nitride based technology.

In three years, NREL should have a bi-colored device that when teamed with blue and deep green can produce a sterling LED with a color-rendering index well over 90, Mascarenhas said.

"It will give you one of the finest color-rendering white lights" and the manufacturing costs shouldn't increase, he said.

"We have a patent on a device that will provide these two colors, as one unit, to industry," Mascarenhas said. "They will arrange them like the mosaic in a fly's eye — our units side by side with the blue and deep green combination, alternating in a pattern."

"From afar, it will look like white. You won't be able to see the individual colors of the mosaic structure."

"We have full confidence that this is achievable," Mascarenhas said.

"The technical things will be solved," he said. "This is practical science, not pie-in-the-sky science."

The resulting white light LED will be intelligent. "We'll be able to electronically control the hue of the lamp," he said. "We can vary the combination of intensities of these four colors on an electronic circuit. By slightly increasing the blue, we can make it more suitable for daylight. By turning down the blue and increasing the reddish yellow, we can make it softer, more suitable for night. We can smoothly control the hue throughout the day like nobody has imagined. "

And, by the way, the move toward all LEDs all the time will save some $120 billion in electricity between now and 2030, the Department of Energy forecasts. Not to mention tens of millions of tons of greenhouse gases.

"This is reality," Mascarenhas said. "This is going to happen."

Setting Another Place at the Periodic Table--International Team Discovers New Super-heavy Element

An international team of scientists from Russia and the United States, including two U.S. Department of Energy national laboratories and two universities, has discovered the newest super-heavy element, element 117. The team included scientists from the Joint Institute of Nuclear Research (Dubna, Russia), the Research Institute for Advanced Reactors (Dimitrovgrad), Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, Vanderbilt University, and the University of Nevada, Las Vegas.

Academician Yuri Oganessian, scientific leader of the Flerov Laboratory of Nuclear Reactions at JINR and spokesperson for the collaboration said, "The discovery of element 117 is the culmination of a decade-long journey to expand the periodic table and write the next chapter in heavy element research."

The team established the existence of element 117 from decay patterns observed following the bombardment of a radioactive berkelium target with calcium ions at the JINR U400 cyclotron in Dubna. The experiment depended on the availability of special detection facilities and dedicated accelerator time at Dubna, unique isotope production and separation facilities at Oak Ridge, and distinctive nuclear data analysis capabilities at Livermore.

"This is a significant breakthrough for science," LLNL director George Miller said. "The discovery of a new element provides new insight into the makeup of the universe and is a testimony to the strength of science and technology at the partner institutions."

"This collaboration and the discovery of element 117 demonstrates the fundamental importance of scientists from different nations and institutions working together to address complex scientific challenges," ORNL Director Thom Mason said. The two-year experimental campaign began at the High Flux Isotope Reactor in Oak Ridge with a 250-day irradiation in the world's most intense neutron flux to produce 22 mg of berkelium. This was followed by 90 days of processing at Oak Ridge to separate and purify the berkelium, target preparation at Dimitrovgrad, 150 days of bombardment at one of the world's most powerful heavy ion accelerators at Dubna, data analysis at Livermore and Dubna, and assessment and review of the results by the team. The entire process was driven by the 320-day half-life of the berkelium target material.

The experiment produced six atoms of element 117. For each atom, the team observed the alpha decay from element 117 to 115 to 113 and so on until the nucleus fissioned, splitting into two lighter elements. In total, 11 new "neutron-rich" isotopes were produced, bringing researchers closer to the presumed "island of stability" of superheavy elements.

The island of stability is a term in nuclear physics that refers to the possible existence of a region beyond the current periodic table where new superheavy elements with special numbers of neutrons and protons would exhibit increased stability. Such an island would extend the periodic table to even heavier elements and support longer isotopic lifetimes to enable chemistry experiments.

Element 117 was the only missing element in row seven of the periodic table. On course to the island of stability, researchers initially skipped element 117 due to the difficulty in obtaining the berkelium target material. The observed decay patterns in the new isotopes from this experiment, as close as researchers have ever approached the island of stability, continue a general trend of increasing stability for superheavy elements with increasing numbers of neutrons in the nucleus. This provides strong evidence for the existence of the island of stability.

"It fills in the gap and gets us incrementally closer than element 116--on the edge," said Ken Moody, one of the LLNL collaborators and a long term veteran of superheavy element research. "The experiments are getting harder, but then I thought we were done 20 years ago."

This discovery brings the total to six new elements discovered by the Dubna-Livermore team (113, 114, 115, 116, 117, and 118, the heaviest element to date). This is the second new element discovery for Oak Ridge (61 and 117). In addition, Oak Ridge isotopes have contributed to the discovery of a total of seven new elements.

Since 1940, 26 new elements beyond uranium have been added to the periodic table.

"These new elements expand our understanding of the universe and provide important tests of nuclear theories," said Vanderbilt University Professor of physics Joe Hamilton. "The existence of the island of stability, a pure theoretical notion in the 1960s, offers the possibility of further expansion of the periodic table with accompanying scientific breakthroughs in the physics and chemistry of the heaviest elements."

Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration. Oak Ridge National Laboratory is managed by UT-Battelle, LLC for the U.S. Department of Energy.