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  • richardmitnick 11:09 am on May 10, 2018 Permalink | Reply
    Tags: , , , LLNL, NIF From the ground up., ,   

    From The Atlantic Magazine: “The National Ignition Facility” 2014 Origins 

    Atlantic Magazine

    From The Atlantic Magazine

    Jan 9, 2014
    Alan Taylor

    At Lawrence Livermore National Laboratory, a federally funded research and development center about 50 miles east of San Francisco, scientists at the National Ignition Facility (NIF) are trying to achieve self-sustaining nuclear fusion — in other words, to create a miniature star on Earth.

    The core of the NIF is a house-sized spherical chamber aiming 192 massive lasers at a tiny target. One recent laser experiment focused nearly 2 megajoules (the energy consumed by 20,000 100-watt light bulbs in one second) of light energy onto a millimeter-sized sphere of deuterium and tritium in a 16-nanosecond pulse. The resulting energetic output, while far short of being a self-sustaining reaction, set a record for energy return, and has scientists hopeful as they fine-tune the targeting, material, and performance of the instruments. The facility itself bristles with machinery and instruments, impressing the producers of the movie Star Trek: Into Darkness, who used it as a film set for the warp core of the starship Enterprise.

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    1. Inside the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, a service system lift allows technicians to access the target chamber interior for inspection and maintenance. The goal of the NIF is to initiate controlled nuclear fusion, in the hopes of creating a new source of energy for our growing world.
    Philip Saltonstall/Lawrence Livermore National Laboratory

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    2. During construction in the late 1990s – NIF’s “Grand Central Station” is its seven-story-tall Target Bay which houses the target chamber as well as the final optics assemblies, cryogenics systems, and diagnostic equipment. The chamber, a sphere ten meters (33 feet) in diameter, is covered with boron-injected concrete to absorb neutrons during NIF experiments. Lawrence Livermore National Laboratory

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    3. U.S. Secretary of Energy Bill Richardson, lower right, christens the 150-ton, 33-foot diameter aluminum laser target chamber at the National Ignition Facility in Lawrence Livermore National Laboratory in Livermore, California, on June 11, 1999. AP Photo/Ben Margot

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    4. The single largest piece of equipment at the NIF is its 130-ton target chamber. The design features 6 symmetric middle plates and 12 asymmetric outer plates, which were poured at the Ravenswood Aluminum Mill in Ravenswood, West Virginia. The plates were shipped to Creusot-Loire Industries in France, where they were heated and then shaped in a giant press. The formed plates were shipped from France to Precision Components Corp. in York, Pennsylvania, where they were trimmed and weld joints prepared. Assembly and welding activities at Lawrence Livermore National Laboratory (seen here) were performed in a temporary cylindrical steel enclosure looking much like an oil or water tank. Lawrence Livermore National Laboratory

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    5. In June 1999, after careful preparation, a rotating crane hoisted the target chamber and gently moved it to the Target Bay. Lawrence Livermore National Laboratory

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    6. After the target chamber was lowered into place, the seven-story walls and roof of the Target Bay were completed. Lawrence Livermore National Laboratory

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    7. The target chamber under construction. Holes in the target chamber provide access for the laser beams and viewing ports for NIF diagnostic equipment.
    Lawrence Livermore National Laboratory

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    8. Power Conditioning System – Peak power for the NIF electrical system exceeds one trillion watts, making it the highest-energy and highest-power pulsed electrical system of its kind. Lawrence Livermore National Laboratory

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    9. The fabrication of melted and rough-cut blanks of laser glass amplifier slabs needed for NIF construction (3,072 pieces) was completed in 2005. The amplifier slabs are neodymium-doped phosphate glass manufactured by Hoya Corporation, USA and SCHOTT North America, Inc. Lawrence Livermore National Laboratory

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    10. The target assembly for NIF’s first integrated ignition experiment is mounted in the cryogenic target positioning system, or cryoTARPOS. The two triangle-shaped arms form a shroud around the cold target to protect it until they open five seconds before a shot. Lawrence Livermore National Laboratory

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    11. A new “tentless” National Ignition Facility target showing the two-millimeter-diameter target capsule in the center of the hohlraum (a specially designed barrel-shaped housing for the target sphere). The tiny capsule is supported by the fill tube used to fill the capsule with fuel and a secondary stabilizing support tube at right. Both tubes are 30 microns in diameter. In previous targets, the capsule was supported by ultrathin plastic membranes known as tents; experiments indicated that the tents might be seeding hydrodynamic instabilities sufficient to interfere with the NIF implosions. Lawrence Livermore National Laboratory

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    12. A NIF target contains a polished capsule about two millimeters in diameter, filled with cryogenic (super-cooled) hydrogen fuel. Lawrence Livermore National Laboratory

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    13. NIF’s final optics inspection system, when extended into the target chamber from a diagnostic instrument manipulator, can produce images of all 192 laser final optics assemblies.
    Jacqueline McBride/Lawrence Livermore National Laboratory

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    14. The National Ignition Facility at Lawrence Livermore National Laboratory requires optics produced from large single crystals of potassium dihydrogen phosphate (KDP) and deuterated potassium dihydrogen phosphate (DKDP). Each crystal is sliced into 40-centimeter-square crystal plates. Traditionally DKDP has been produced by methods requiring approximately two years to grow a single crystal. With the development of rapid growth methods for KDP, the time required to grow a crystal has been reduced to just two months. NIF requires 192 optics produced from traditionally grown DKDP and 480 optics rapidly grown from KDP. Approximately 75 production crystals were grown totaling a weight of nearly 100 tons. Lawrence Livermore National Laboratory

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    15. This view from the bottom of the chamber shows the target positioner being inserted. Pulses from NIF’s high-powered lasers race toward the Target Bay at the speed of light. They arrive at the center of the target chamber within a few trillionths of a second of each other, aligned to the accuracy of the diameter of a human hair. Philip Saltonstall/Lawrence Livermore National Laboratory

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    16. Seen from above, each of NIF’s two identical laser bays has two clusters of 48 beamlines, one on either side of the utility spine running down the middle of the bay, eventually reaching the target chamber. Jacqueline McBride/Lawrence Livermore National Laboratory

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    17. Temperatures of 100 million degrees and pressures extreme enough to compress the target to densities up to 100 times the density of lead are created in the target chamber. Surrounding the target is diagnostic equipment capable of examining in minute detail the arrival of the laser beams and the reaction of the target to this sudden deposition of energy. Jacqueline McBride/Lawrence Livermore National Laboratory

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    18. The interior of the NIF target chamber. The service module carrying technicians can be seen on the left. The target positioner, which holds the target, is on the right.
    Lawrence Livermore National Laboratory

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    19. Lawrence Livermore National Laboratory technicians John Hollis (right) and Jim McElroy install a SIDE camera in the target bay of the National Ignition Facility (NIF). The camera was the last of NIF’s 6,206 various opto-mechanical and controls system modules to be installed. Jacqueline McBride/Lawrence Livermore National Laboratory

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    20. Director Edward Moses briefed California Governor Arnold Schwarzenegger at the NIF target chamber, on November 10, 2008. Jacqueline McBride/Lawrence Livermore National Laboratory

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    21. NIF’s millimeter-sized targets must be designed and fabricated to meet precise specifications for density, concentricity and surface smoothness for NIF experiments. LLNL scientists and engineers have developed a precision robotic assembly machine to manufacture the small and complex fusion ignition targets. Lawrence Livermore National Laboratory

    22
    22. California Governor Arnold Schwarzenegger examines a model of a target while touring the National Ignition Facility in Livermore, California, on November 10, 2008. AP Photo/Lea Suzuki, Pool

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    23. A tall view of the NIF target chamber. Jacqueline McBride/Lawrence Livermore National Laboratory

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    24. A new viewing window recently installed on the NIF Target Chamber allows members of the NIF team and visitors to see inside the chamber while it is vacuum-sealed for experiments. NIF Team members Bruno Van Wonterghem (left), Jim Nally (pointing) and Rod Saunders watch through the viewing window as the Final Optics Damage Inspection System is deployed.
    Lawrence Livermore National Laboratory

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  • richardmitnick 10:23 am on May 10, 2018 Permalink | Reply
    Tags: , , , , Experiments shed new light on supernovae, LLNL,   

    From Lawrence Livermore National Laboratory: “Experiments shed new light on supernovae” 

    From Lawrence Livermore National Laboratory

    May 9, 2018
    Breanna Bishop
    bishop33@llnl.gov
    925-423-9802

    1
    False-color Chandra X-ray Observatory image of supernova remnant E0102.2-72, the spectacular remains of a core-collapse supernova located about 190,000 light-years away in the Small Megallanic Cloud in the constellation Tucana. The expanding multimillion-degree remnant is about 30 light-years across. What appear to be Rayleigh-Taylor “spikes” can be seen in the outer edge of the expanding supernova remnant. Credit: (X-ray) NASA/CXC/MIT/D. Dewey et al. and NASA/CXC/SAO/J. DePasquale; (optical) NASA/STScI

    NASA/Chandra X-ray Telescope

    NASA/ESA Hubble Telescope

    Small Magellanic Cloud. 10 November 2005. ESA/Hubble and Digitized Sky Survey 2

    Experiments on Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) are providing scientists with new insights into the turbulent after-effects of a supernova explosion. The studies also could inform efforts to achieve self-sustaining nuclear fusion on NIF and other high-energy laser systems.

    When stars of a certain mass collapse and then violently explode, material called ejecta expands rapidly and is then decelerated by the surrounding circumstellar medium. This results in Rayleigh-Taylor (RT) hydrodynamic instabilities — the mixing of denser with less-dense material.

    The same instabilities can affect the performance of inertial confinement fusion (ICF) and high-energy density (HED) science experiments such as those conducted on NIF, the world’s highest-energy laser system. The instabilities can cause too much target capsule material to mix with the fuel, quenching the fusion reaction.

    The supernova studies, conducted by an international team of researchers led by the University of Michigan (UM) and LLNL physicists Hye-Sook Park and Channing Huntington, found that high energy fluxes and the resulting heat could reduce RT growth in supernova remnants (SNRs) — something previous astrophysics models had not considered. The results were reported in a Nature Communications paper published online on April 19.

    “Rayleigh-Taylor instabilities have been studied for more than 100 years,” said Carolyn Kuranz, director of UM’s Center for Laser Experimental Astrophysical Research and an associate research scientist of climate and space sciences and engineering. “These instabilities are important in supernova dynamics, but the effects of these high-energy fluxes, these mechanisms that cause heating, have never been studied in this context.” The researchers said realistic models of SNRs “must account for the effects of thermal conduction to accurately predict their evolution at epochs immediately following the shock breakout.”

    “These heating mechanisms reduce mixing and can have a dramatic effect on the evolution of a supernova,” Kuranz said. “In our experiment, we found that mixing was reduced by 30 percent and that reduction could continue to increase over time.”

    That finding is potentially important for NIF because “the Rayleigh-Taylor instability is a very basic ingredient in understanding NIF’s performance,” Park said. “The effect of large energy flux and the basic science of the RT theory and application are quite relevant to ICF and HED science.”

    Involving NIF users

    The supernova studies originated shortly after NIF became operational as a way to begin involving academic institutions in NIF experiments — an effort that has grown into the current Discovery Science program in which external institutions compete for time on NIF to conduct experimental campaigns (see NIF Users Bring Ideas and Energy to Discovery Science).

    “We designed that experiment way back in 2009,” Park said. “This is one of the original Discovery Science programs — the first one, actually. The University of Michigan was doing supernova RT (SNRT) experiments on OMEGA (the OMEGA Laser at the University of Rochester), so we decided we could think of a similar experiment, but with a new physics goal, on NIF.”

    U Rochester Omega Laser


    U Rochester OMEGA EP Laser System


    National Ignition Facility at LLNL

    U- was studying RT instabilities in the context of the cosmic shocks produced by supernova explosions, “and NIF is really good at generating high-energy fluxes, using the hohlraum, that are transported via thermal heat conduction and radiation transport — that’s one of the things that we can do easily,” Park said.

    “So the idea was to study the effect of high-energy flux on RT growth that may be important to supernova evolution. Using NIF, we decided to study the difference in RT growth between the low-flux (230-electron-volt, or eV) and high-flux (325-eV) radiation drive cases.”

    There were setbacks in the early years, however; NIF diagnostics at the time weren’t up to the task of providing the data required by the researchers. “A 325-eV hohlraum is really hot (about 3.8 million degrees Centigrade), generating a huge amount of background ‘noise,’” Park said. “A typical ICF deuterium-tritium (fusion) shot uses about 290 eV (3.4 million degrees C). Our 325-eV hohlraum is 400,000 degrees hotter. So our signal from our initial experiment got swamped by the background on the time-integrating X-ray film.”

    The experiments regained momentum when Park became aware of a new experimental platform developed by Los Alamos National Laboratory (LANL) (see Shock/Shear’ Experiments Shed Light on Turbulent Mix). “We designed a target to fit in the halfraum (the half-hohlraum used in the shock/shear experiments),” Park said, “and we did a first set of experiments with a low-flux drive.

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    (a) Schematic of the NIF SNRT target; laser beams incident on the gold hohlraum create the X-ray drive while additional beams impact the large-area backlighter to create the diagnostic X-ray source. A plastic shock tube is attached to the hohlraum. The soft X-rays from the hohlraum create a shock wave in the plastic layer inside the shock tube (b), which decays into a blast wave before crossing the unstable interface and entering the foam. The diagnostic X-ray source creates radiographs by being preferentially absorbed by a tracer layer in the center of the plastic. (c and d) X-ray radiographs of the experiment; the plasma flows upward, and the dark fingers are due to RT instability growth. The color bar indicates the relative transmission for (c) the high-flux case taken at 13 nanoseconds and (d) the low-flux case at 34 nanoseconds. The high-flux case shows significantly lower RT growth.

    “We got great data with the low-flux hohlraum,” she said, “but we also needed to do a high-flux drive case with which to compare it. The experiment is all about comparing low drive and high drive. This (shock/shear) platform was never done at high drive, and unless you carefully design the target it wouldn’t work. We had to incorporate additional features to generate a high-flux drive that didn’t generate significant background and that didn’t hamper our observations.”

    With a new target designed and deployed, the researchers were able to conduct a successful series of nine shots using both low-flux and high-flux drives that demonstrated the effect of high-flux radiation on the subsequent RT growth. They used the results to explore how the large energy fluxes present in supernovae could affect the structure of SNRs and Rayleigh–Taylor growth.

    “In analyzing the comparison with supernova SN1993J, a Type II supernova,” they said, “we found that the energy fluxes produced by heat conduction appear to be larger than the radiative energy fluxes, and large enough to have dramatic consequences.”

    According to Park, future experiments in the campaign will attempt to measure the temperature and density in the shock-formation region. “Then we can be more creative about creating more heat flux in the NIF environment to more closely mimic the astrophysical conditions,” she said. “There are a lot of windows of opportunity.”

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    NIF
    Members of the team studying supernova remnants on NIF (from left): NIF Operations Manager Bruno Van Wonterghem, Channing Huntington, Bruce Remington, Carolyn Kuranz, Kirk Flippo and Hye-sook Park.

    Joining Kuranz, Park and Huntington on the paper were Aaron Miles, Bruce Remington, Harry Robey, Kumar Raman, Steve MacLaren, Shon Prisbrey, Russell Wallace and Dan Kalantar from LLNL; along with John Kline, Kirk Flippo, Willow Wan and Forrest Doss from LANL; Eric Harding from Sandia National Laboratories; Christine Krauland and Emilio Giraldez from General Atomics; and researchers from UM and Florida State University; Ben Gurion, University of the Negev in Israel; and MJ Grosskopf, Simon Fraser University, Canada.

    -Charlie Osolin/LLNL

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  • richardmitnick 1:24 pm on May 2, 2018 Permalink | Reply
    Tags: ELI Beamlines facility, , LLNL,   

    From Lawrence Livermore National Laboratory: “Lasers, photonics and powerful partnerships” 

    Lawrence Livermore National Laboratory

    April 30, 2018

    Stephen Wampler
    wampler1@llnl.gov
    925-423-3107

    1
    The commercialization of laser peening technology — similar to working a metal’s surface with a ballpeen hammer — has been one of the most successful transfers of Lawrence Livermore technology to industry. The laser peening technology, which was originally developed by Battelle in the 1970s and was first commercialized by LSP technologies in 1975, was upgraded by LLNL researchers working with Metal Improvement Co. Inc.

    The world’s most energetic laser sits in a secure, guarded federal laboratory, but its impact stretches far beyond the one-square-mile site of Lawrence Livermore National Laboratory (LLNL).


    National Ignition Facility at LLNL

    Since the outset, technologies developed or improved at the Laboratory have led to industry-defining partnerships and products that make millions of Americans’ lives better every day. Even if they’ve never heard of them.

    “Nearly all of us at this point have flown on an airplane with turbine blades that were laser peened with technology that Livermore commercialized years ago,” said Craig Siders, senior scientist and commercial technology development leader in NIF & Photon Science’s Advanced Photon Technologies program. Laser peening — using intense laser light to improve the quality of a material — had been invented in the 1970s, but had not achieved significant market penetration until LLNL introduced a new laser architecture that provided critical new functionality to the technology. Laser peening is commonplace now, thanks in part to Laboratory research that was spun off into the private sector.

    “It’s technology that’s absolutely in the hands of industry today, and the Lab is now out of the peening business, because it’s the right thing to do,” Siders added. “LLNL’s innovations in laser technology were a critical component in making peening a success story.”

    In 2003, former LLNL scientists Lloyd Hackel and Brent Dane, together with LLNL CRADA partner Metal Improvement Company (MIC), today part of Curtiss-Wright Corporation, brought the benefits of laser peening to the economy as a whole. The Laboratory’s commercialization process worked: Lawrence Livermore helped develop a cutting-edge technology until it was mature enough to stand on its own. Today, laser peening can exponentially extend the lifespan of an F-22 fighter jet’s airframe. MIC has treated jet engine fan blades on every Airbus A340 passenger plane and hundreds of Boeing 777s and 787s. It’s the third best royalty-producing technology in Lab history.

    And now, LLNL is offering the opportunity to license and commercialize an extension of laser-peening technology called high velocity laser accelerated deposition (HVLAD) for controlled laser-driven explosive bonding. HVLAD was selected by R&D Magazine as a winner of an R&D 100 Award in 2012.

    “We’re in the process of satisfying the primary goals of the Lab — pursuing national security, stockpile stewardship and fundamental science,” said David Dawes, a business development executive in LLNL’s Innovation and Partnerships Office (IPO). “All of these things can help generate spinoffs that are commercially important.”

    Dawes is a primary conduit between LLNL and industry. When scientists believe they have a breakthrough, they often come to Dawes for advice. Whether that conversation leads to a record of invention, a patent or a Collaborative Research and Development Agreement (CRADA), he’s instrumental in helping keep up with the laser and optics industry and matching research with opportunity. Many of NIF’s 40,000 brand new, specialized optical components represent commercialization opportunities, thanks to the new technologies developed to create them. As the Laboratory advances each dimension of laser and optics technology, companies can follow behind and adopt them as they become available.

    “All of these features involve leading-edge technologies that are important to the laser industry as a whole as they scale up their power levels,” Dawes says. “There’s marketable technologies there that we’re currently talking to a number of companies about licensing.” For other examples of current laser and optics technologies available for commercialization, see the IPO website.

    In particular, Dawes brings 35 years of experience in the industry (and some patents of his own) to bear on IPO’s work connecting research with companies. Maintaining long-standing relationships with industry and academic leaders, setting up visits to Livermore and monitoring trade and scientific journals are important tricks of Dawes’ trade. IPO screens every paper slated for journal publication in order to identify possibilities for future commercialization. Details on ongoing CRADAs and licensing are scarce, but the Laboratory’s track record speaks for itself.

    “The Lab has had a significant impact, historically, on the market,” said Siders. “There’s a lot of goodwill out there, built up with past success stories like peening.”

    Pushing the frontiers in lasers

    Anticipating the next generation of lasers is especially fertile ground for partnerships with LLNL’s NIF & Photon Science researchers. Scientists expect these lasers to be so powerful, current optics technologies won’t be able to withstand them.

    “When I was a professor, I called this the first law of directed energy,” said Siders. “Thou Shalt Destroy the Target Before You Destroy the Laser.”

    A current CRADA with Electro-Optics Technology (EOT) aims to address one of these. Known for their diode-like Faraday isolators — permitting light to pass in one direction only while preventing harmful backward propagation — EOT, among other industry leaders, got a call from Laboratory researchers with experience in high-power laser performance and component cooling looking for pushing the limits of isolator technologies. EOT was looking to advance applications of new materials, which fit perfectly into the needs for high-power isolators. Together, EOT and LLNL are close to producing a marketable product that will benefit the laser industry as a whole and prepare the Laboratory for advanced high-power laser systems.

    One such system is the new HAPLS pulsed-laser being installed in the European Union’s Extreme Light Infrastructure (ELI) Beamlines facility in the Czech Republic.

    The L3-HAPLS laser system, installed at the ELI Beamlines Research Center in Dolní Břežany, Czech Republic.

    HAPLS (the High-Repetition-Rate Advanced Petawatt Laser System designed, developed and delivered by LLNL) integrates a number of new, efficient, high-power laser and optical technologies that Siders believes will eventually lead to the lasers necessary for inertial fusion energy. It’s a powerful tool for its customer, ELI Beamlines, but it’s also a window for scientists into the future of high-power pulsed lasers and a possible fusion power plant.

    ELI Beamlines facility, Research Center in Dolní Břežany, Czech Republic

    2
    LLNL researchers partnered with Lasertel Inc. to develop the world’s highest peak power laser diode arrays, representing total peak power of 3.2 megawatts, to power the High-Repetition-Rate Advanced Petawatt Laser System. To drive the diode arrays, LLNL developed and patented a new type of pulsed-power system, which supplies the arrays with electrical power by drawing energy from the grid and converting it to extremely high-current, precisely-shaped electrical pulses. Photo by Damien Jemison/LLNL.

    “We’re actually looking to provide benefits back from investments that this nation and the Department of Energy have made over four or five decades of research into inertial confinement fusion and inertial fusion energy,” said Siders. While luck is always a component, he added that strategy and ongoing communication are key to maintaining fruitful partnerships.

    “By working with industry in that way, we can get products on the market that everyone can benefit from,” said Siders. “That helps move the nation’s laser technology capabilities forward. That’s a good news story.”

    In addition to the significant benefits Lawrence Livermore’s laser and optics research can provide to industry, commercialization can also have a tremendous impact on the scientists themselves.

    “I often tell folks here that there’s a future where they could walk into almost any lab in the world, point to something and say ‘hey, that’s my work,’” said Siders. “That’s immensely rewarding.”

    -Ben Kennedy

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  • richardmitnick 4:47 pm on April 17, 2018 Permalink | Reply
    Tags: , LLNL, , Ramp compression, Superearths   

    From Lawrence Livermore National Laboratory: “Ramp compression of iron provides insight into core conditions of large rocky exoplanets” 

    Lawrence Livermore National Laboratory

    April 16, 2018
    Breanna Bishop
    bishop33@llnl.gov
    925-423-9802

    1
    High-power lasers at the National Ignition Facility are focused onto a multi-stepped iron sample at the center of the 10-meter-diameter target chamber. These experiments measure the equation of state of iron under core conditions of large rocky exoplanets.

    In a paper published today by Nature Astronomy , a team of researchers from Lawrence Livermore National Laboratory (LLNL), Princeton University, Johns Hopkins University and the University of Rochester have provided the first experimentally based mass-radius relationship for a hypothetical pure iron planet at super-Earth core conditions.

    This discovery can be used to evaluate plausible compositional space for large, rocky exoplanets, forming the basis of future planetary interior models, which in turn can be used to more accurately interpret observation data from the Kepler space mission and aid in identifying planets suitable for habitability.

    “The discovery of large numbers of planets outside our solar system has been one of the most exciting scientific discoveries of this generation,” said Ray Smith, a physicist at LLNL and lead author of the research. “These discoveries raise fundamental questions. What are the different types of extrasolar planets and how do they form and evolve? Which of these objects can potentially sustain surface conditions suitable for life? To address such questions, it is necessary to understand the composition and interior structure of these objects.”

    Of the more than 4,000 confirmed and candidate extrasolar planets, those that are one to four times the radius of the Earth are now known to be the most abundant. This size range, which spans between Earth and Neptune, is not represented in our own solar system, indicating that planets form over a wider range of physical conditions than previously thought.

    “Determining the interior structure and composition of these super-Earth planets is challenging but is crucial to understanding the diversity and evolution of planetary systems within our galaxy,” Smith said.

    As core pressures for even a 5×-Earth-mass planet can reach as high as 2 million atmospheres, a fundamental requirement for constraining exoplanetary composition and interior structure is an accurate determination of the material properties at extreme pressures. Iron (Fe) is a cosmochemically abundant element and, as the dominant constituent of terrestrial planetary cores, is a key material for studying super-Earth interiors. A detailed understanding of the properties of iron at super-Earth conditions is an essential component of the team’s experiments.

    The researchers describe a new generation of high-power laser experiments, which use ramp compression techniques to provide the first absolute equation of state measurements of Fe at the extreme pressure and density conditions found within super-Earth cores. Such shock-free dynamic compression is uniquely suited for compressing matter with minimal heating to TPa pressures (1 TPa = 10 million atmospheres).

    The experiments were conducted at the LLNL’s National Ignition Facility (NIF).

    NIF, the world’s largest and most energetic laser, can deliver up to 2 megajoules of laser energy over 30 nanoseconds and provides the necessary laser power and control to ramp compress materials to TPa pressures. The team’s experiments reached peak pressures of 1.4 TPa, four times higher pressure than previous static results, representing core conditions found with a 3-4x Earth mass planet.

    “Planetary interior models, which rely on a description of constituent materials under extreme pressures, are commonly based on extrapolations of low-pressure data and produce a wide range of predicated material states. Our experimental data provides a firmer basis for establishing the properties of a super-Earth planet with a pure iron planet,” Smith said. “Furthermore, our study demonstrates the capability for determination of equations of state and other key thermodynamic properties of planetary core materials at pressures well beyond those of conventional static techniques. Such information is crucial for advancing our understanding of the structure and dynamics of large rocky exoplanets and their evolution.”

    Future experiments on NIF will extend the study of planetary materials to several TPa while combining nanosecond X-ray diffraction techniques to determine the crystal structure evolution with pressure.

    Co-authors include Dayne Fratanduono, David Braun, Peter Celliers, Suzanne Ali, Amalia Fernandez-Pañella, Richard Kraus, Damian Swift and Jon Eggert from LLNL; Thomas Duffy from Princeton University; June Wicks from Johns Hopkins University; and Gilbert Collins from the University of Rochester.
    Tags: Lasers / NIF / National Ignition Facility

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  • richardmitnick 10:31 am on April 13, 2018 Permalink | Reply
    Tags: , LLNL, NIF petawatt-class Advanced Radiographic Capability (ARC),   

    From LLNL: “A powerful new source of high-energy protons” 

    Lawrence Livermore National Laboratory

    April 12, 2018
    Breanna Bishop
    bishop33@llnl.gov
    925-423-9802

    1
    Illustration of a typical experiment on high-energy, or fast, proton acceleration from a laser-irradiated solid target. Credit: Andrea Macchi, et al., Rev. Mod. Phys., Vol. 85, No. 2, April–June 2013

    Nearly 20 years ago, researchers conducting experiments on Lawrence Livermore National Laboratory’s (LLNL) Nova Petawatt laser system — the world’s first quadrillion-watt laser — discovered that when the system’s intense short-pulse laser beams struck a thin foil target, an unexpected torrent of high-energy electrons and protons streamed off the back of the target.

    (LLNL) Nova Petawatt laser system

    Earlier this month, an international team of researchers used the Nova Petawatt’s successor, the National Ignition Facility’s (NIF) petawatt-class Advanced Radiographic Capability (ARC), to begin developing an experimental platform that promises to turn Nova’s surprise discovery into a powerful new source of protons to study the extreme conditions deep inside the planets and the stars, enhance targeted tumor therapy and advance the frontiers of high energy density (HED) science.

    LLNL National Ignition Facility’s (NIF) petawatt-class Advanced Radiographic Capability (ARC)

    In two NIF Discovery Science experiments, the researchers fired four ARC beamlets at a 33-micron-thick titanium foil, setting up a strong electrostatic sheath field called a Target Normal Sheath Accelerating (TNSA) field perpendicular to the target (normal is a geometric term for perpendicular). As the field blew away from the back of the target, it accelerated high-energy protons and ions from the contamination layer of proton-rich hydrocarbons and water coating the target’s surface, all moving rapidly in the same direction.

    “The results were as good as we had hoped for,” said LLNL physicist Tammy Ma, the campaign’s principal investigator. “It was definitely a win. ARC is not as intense as a lot of other short-pulse lasers, so some in the community were concerned that the intensities might not be sufficient to generate these beams. But (the result) was more protons than we expected with energies approaching 20 MeV (million electron volts) — definitely a source that will enable other applications and cool physics.”

    In the experiments, two of NIF’s 192 beamlines were split to form the four short-pulse ARC beamlets. The beamlets were fired simultaneously for 10 or one picoseconds (trillionths of a second), generating up to 200 terawatts (trillion watts) of power per beamlet. The total of about 700 terawatts in the second experiment was the highest peak power yet generated on NIF.

    ARC’s high peak power is made possible by a process called chirped-pulse amplification, in which a short, broadband pulse generated by an oscillator is stretched in time to reduce its peak intensity, then amplified at intensities below the damage threshold in the laser amplifiers, and finally compressed to a short pulse and highest peak power in large compressor vessels.

    The new Discovery Science platform, supported by LLNL’s Laboratory Directed Research and Development (LDRD) program, is designed to study the physics of particle-beam generation at previously unexplored ultra-high short-pulse laser energies and long pulse durations. Coupled to NIF’s 1.8 million joules of ultraviolet energy, the capability will enable myriad HED applications and allow the creation and study of extreme states of matter.

    3
    After amplification in the NIF laser, the ARC beamlets are compressed in the Target Bay and focused to Target Chamber Center.

    NIF is the world’s only facility capable of achieving conditions like those in the interiors of stars and giant planets. Using ARC short-pulse generated proton beams for ultrafast heating of matter to extreme states will enable opacity and equation-of-state measurements at unprecedented energy-density states.

    In addition, “protons deposit their energy very specifically,” noted LLNL postdoc Derek Mariscal, lead experimentalist for the project. “That’s why protons are promising for applications such as tumor therapy. You can send a beam of protons toward a tumor and get it to deposit all of its energy exactly where you want it to without damaging other areas of the body.

    “Likewise with a solid material,” he said. “(The proton beam) deposits its energy where you want it to very quickly, so you can heat up a material really fast before it has time to hydrodynamically expand — your material stays dense, and that’s the name of the game — high energy, high density.”

    Once the proton-acceleration platform has been demonstrated and understood, Mariscal said, the next step in the project will be to fire the ARC beams at a deuterated carbon (CD) foil to generate a beam of deuterons. “You could impact those onto a second foil, like lithium fluoride or beryllium, and then you get a beam of neutrons — a real, laser-like neutron source, only using two beams of NIF instead of all 192.”

    Along with managing the project, Ma serves as the LLNL liaison with the collaborating institutions: the University of California, San Diego, General Atomics, Oxford University, the SLAC National Accelerator Laboratory, Rutherford Appleton Laboratory, Los Alamos National Laboratory, the University of Alberta and Osaka University. Scott Wilks, who was a member of the team that discovered the TNSA process on the Nova Petawatt laser, is coordinating the theory and modeling effort.

    Other LLNL team members are Jackson Williams, Nuno Lemos, Hui Chen, Prav Patel, Bruce Remington, Andrew MacPhee, Andreas Kemp, Matt Mcmahon, Art Pak, Sasha Rubenchik, Max Tabak, Steve Hatchett (retired), Mark Sherlock, Andy Mackinnon, Anthony Link, Mark Hermann and Constantin Haefner.

    4
    Members of the ARC proton acceleration team outside the NIF Control Room: Front row, from left: Derek Mariscal (LLNL), Alessio Morace (Osaka University), Krish Bhutwala (UCSD), Tammy Ma (LLNL), Alex Savin (Oxford University), Chris McGuffey (UCSD), and Mingsheng Wei (GA). Back row: Graeme Scott (Rutherford Appleton Laboratory), Joohwan Kim (UCSD), Mark Sherlock (LLNL), Scott Wilks (LLNL), Andreas Kemp (LLNL), Nuno Lemos (LLNL), Sasha Rubenchik (LLNL), Jackson Williams (LLNL), Chandra Curry (University of Alberta), Constantin Haefner (LLNL) and Max Tabak (LLNL). Not pictured: Bruce Remington, Hui Chen, Prav Patel, Matthew Mcmahon, Andrew MacPhee, Andy Mackinnon, Mark Hermann and Steve Hatchett (LLNL); Farhat Beg, Pierre Forestier-Colleoni, and Brandon Edghill (UCSD); Peter Norreys (Oxford University); Yasuhiko Sentoku and Natsumi Iwata (Osaka University); Shaun Kerr (University of Alberta); Alex Zylstra (LANL); David Neely (RAL); and Mario Manuel (GA). Credit: Jason Laurea

    The proton acceleration shots were among a weeklong series of Discovery Science experiments on NIF. Four other campaigns studied planar direct-drive hydrodynamics, the iron melt curve for studying magnetospheres and exoplanets, high-pressure compressed carbon and laser-driven magnetic field generation. Principal investigators for those experiments were Alexis Casner from the University of Bordeaux, Russell Hemley from the George Washington University and the Capital/DOE Alliance Center, Justin Wark from Oxford University and Brad Pollock from LLNL.

    -Charlie Osolin

    See the full article here .

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  • richardmitnick 9:05 pm on March 19, 2018 Permalink | Reply
    Tags: , LLNL, , , , ,   

    From LLNL: “Breaking the Law: Lawrence Livermore, Department of Energy look to shatter Moore’s Law through quantum computing” 


    Lawrence Livermore National Laboratory

    March 19, 2018
    Jeremy Thomas
    thomas244@llnl.gov
    925-422-5539

    1
    Lawrence Livermore National Laboratory physicist Jonathan DuBois, who heads the Lab’s Quantum Coherent Device Physics (QCDP) group, examines a prototype quantum computing device designed to solve quantum simulation problems. The device is kept inside a refrigerated vacuum tube (gold-plated to provide solid thermal matching) at temperatures colder than outer space. Photos by Carrie Martin/LLNL.

    The laws of quantum physics impact daily life in rippling undercurrents few people are aware of, from the batteries in our smartphones to the energy generated from solar panels. As the Department of Energy and its national laboratories explore the frontiers of quantum science, such as calculating the energy levels of a single atom or how molecules fit together, more powerful tools are a necessity.

    “The problem basically gets worse the larger the physical system gets — if you get beyond a simple molecule we have no way of resolving those kinds of energy differences,” said Lawrence Livermore National Laboratory (LLNL) physicist Jonathan DuBois, who heads the Lab’s Quantum Coherent Device Physics (QCDP) group. “From a physics perspective, we’re getting more and more amazing, highly controlled physics experiments, and if you tried to simulate what they were doing on a classical computer, it’s almost at the point where it would be kind of impossible.”

    In classical computing, Moore’s Law postulates that the number of transistors in an integrated circuit doubles approximately every two years. However, there are indications that Moore’s Law is slowing down and will eventually hit a wall. That’s where quantum computing comes in. Besides busting through the barriers of Moore’s Law, some are banking on quantum computing as the next evolutionary step in computers. It’s on the priority list for the National Nuclear Security Administration’s Advanced Simulation and Computing (ASC) program,,which is investigating quantum computing, among other emerging technologies, through its “Beyond Moore’s Law” project. At LLNL, staff scientists DuBois and Eric Holland are leading the effort to develop a comprehensive co-design strategy for near-term application of quantum computing technology to outstanding grand challenge problems in the NNSA mission space.

    Whereas the desktop computers we’re all familiar with store information in binary forms of either a 1 or a zero (on or off), in a quantum system, information can be stored in superpositions, meaning that for a brief moment, mere nanoseconds, data in a quantum bit can exist as either one or zero before being projected into a classical binary state. Theoretically, these machines could solve certain complex problems much faster than any computers ever created before. While classical computers perform functions in serial (generating one answer at a time), quantum computers could potentially perform functions and store data in a highly parallelized way, exponentially increasing speed, performance and storage capacity.

    LLNL recently brought on line a full capability quantum computing lab and testbed facility under the leadership of quantum coherent device group member Eric Holland. Researchers are performing tests on a prototype quantum device birthed under the Lab’s Quantum Computing Strategic Initiative. The initiative, now in its third year, is funded by Laboratory Directed Research & Development (LDRD) and aims to design, fabricate, characterize and build quantum coherent devices. The building and demonstration piece is made possible by DOE’s Advanced Scientific Computing Research (ASCR), a program managed by DOE’s Office of Science that is actively engaged in exploring if and how quantum computation could be useful for DOE applications.

    LLNL researchers are developing algorithms for solving quantum simulation problems on the prototype device, which looks deceptively simple and very strange. It’s a cylindrical metal box, with a sapphire chip suspended in it. The box is kept inside a refrigerated vacuum tube (gold-plated to provide solid thermal matching) at temperatures colder than outer space — negative 460 degrees Fahrenheit. It’s highly superconductive and faces zero resistance in the vacuum, thus extending the lifetime of the superposition state.

    “It’s a perfect electrical conductor, so if you can send an excitation inside here, you’ll get electromagnetic (EM) modes inside the box,” DuBois explained. “We’re using the space inside the box, the quantized EM fields, to store and manipulate quantum information, and the little chip couples to fields and manipulates them, determining the fine splitting in energies between different quantum states. These energy differences are what you use to make changes in quantum space.”

    To “talk” to the box, researchers are using an arbitrary wave form generator, which creates an oscillating signal– the timing of the signal determines what computation is being done in system. DuBois said the physicists are essentially building a quantum solver for Schrödinger’s equation, the bases for almost all physics and the determining factor for the dynamics of a quantum computing system.

    “It turns out that’s actually very hard to solve, and the bigger the system is, the size of what you need to keep track of blows up exponentially,” DuBois said. “The argument here is we can build a system that does that naturally — nature is basically keeping track of all those degrees of freedom for us, and so if we can control it carefully we can get it to basically emulate the quantum dynamics of some problem we’re interested in, a charge transfer in quantum chemistry or biology problem or scattering problem in nuclear physics.”

    Finding out how the device will work is part of the mission of DOE’s Advanced Quantum-Enabled Simulation (AQuES) Testbed Pathfinder program, which is analyzing several different approaches to creating a functional, useful quantum computer for basic science and use in areas such as determining nuclear scattering rates, the electronic structure in molecules or condensed matter or understanding the energy levels in solar panels. In 2017, DOE awarded $1.5 million over three years to a team including DuBois and Lawrence Berkeley National Laboratory physicists Irfan Siddiqi and Jonathan Carter. The team wants to determine the underlying technology for a quantum system, develop a practical, usable quantum computer and build quantum capabilities at the national labs to solve real-world problems.

    The science of quantum computing, according to DuBois, is “at a turning point.” Within the three-year timeframe, he said, the team should be able to assess what type of quantum system is worth pursuing as a testbed system. The researchers first want to demonstrate control over a quantum computer and solve specific quantum dynamics problems. Then, they want to set up a user facility or cloud-based system that any user could log into and solve complex quantum physics problems.

    “There are multiple competing approaches to quantum computing; trapping ions, semiconducting systems, etc., and all have their quirks — none of them are really at the point where it’s actually a quantum computer,” DuBois said. “The hardware side, which is what this is, the question is, ‘what are the first technologies that we can deploy that will help bridge the gap between what actually exists in the lab and how people are thinking of these systems as theoretical objects?'”

    Quantum computers have come a long way since the first superconducting quantum bit, or “qubit,” was created in 1999. In last nearly 20 years, quantum systems have improved exponentially, evidenced by the life span of the qubit’s superposition, or how long it takes the qubit to decay into 0 or 1. In 1999 that figure was a nanosecond. Currently, systems are up to tens to hundreds of milliseconds, which may not sound like much, but every year, the lifetime of the quantum bit has doubled.

    For the Testbed project, LLNL’s first generation quantum device will be roughly 20 qubits, DuBois said, large enough to be interesting, but small enough to be useful. A system of that size could potentially reduce the time it takes for most current supercomputing systems to perform quantum dynamics calculations from about a day down to mere microseconds, DuBois said. To get to that point, LLNL and LBNL physicists will need to understand how to design systems that can extend the quantum state.

    “It needs to last long enough to be quantum and it needs to be controllable,” DuBois said. “There’s a spectrum to that; the bigger the space is, the more powerful it has to be. Then there’s how controllable it would be. The finest level of control would be to change the value to anything I want. That’s what we’re aiming for, but there’s a competition involved. We want to hit that sweet spot.”

    See the full article here .

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  • richardmitnick 8:33 am on March 2, 2018 Permalink | Reply
    Tags: , , , LLNL, Raman spectroscopy diagnostics, Synchrotron X-ray diffraction,   

    From LLNL: “Earth’s core metals react well to electrons” 


    Lawrence Livermore National Laboratory

    March 1, 2018

    Anne M Stark
    stark8@llnl.gov
    925-422-9799

    1
    LLNL scientists discovered that at the thermodynamic conditions in Earth’s core, metals such as iron and nickel become electronegative and attract electrons. Image by Adam Connell/TID.

    At temperatures and pressures found on Earth’s surface, metallic elements are electropositive and lose their valence electrons to form positively charged cations. Metals have free electrons that naturally form compounds with electronegative elements. For example, iron reacts with oxygen to form Fe2O3 – commonly referred to as rust.

    In contrast, noble gas elements (NGEs), such as argon, neon and xenon — considered the most chemically inert elements – show very little reactivity with other elements.

    However, in the Earth’s core, the reaction of metals with NGEs is quite different. Lawrence Livermore National Laboratory (LLNL) scientists, in collaboration with researchers at the University of Saskatchewan (UoS), the Carnegie Geophysical Laboratory (GL) and the University of Chicago, challenged this basic chemical phenomenon by examining the possible reaction between iron and nickel with xenon at thermodynamic conditions like those found in Earth’s core. Using synchrotron X-ray diffraction and Raman spectroscopy diagnostics in concert with first principles calculations, they discovered that it is possible to create stable xenon iron/nickel intermetallic compounds at Earth-core thermodynamic conditions. The experimental team used a natural iron meteorite, which fell on the Sikhote-Alin mountains in Russia, as a proxy to Earth’s core composition.

    The research is published in the Feb. 28 edition of Physical Review Letters.

    “We targeted iron/nickel-xenon reactions at pressures greater than 2 million times Earth’s atmospheric (surface) pressure and temperatures above 2000 Kelvin to simulate thermodynamic conditions representative of Earth’s core. Our aim was to solve the missing xenon paradox, that is xenon depletion in Earth’s atmosphere,” explained lead author, Elissaios (Elis) Stavrou, an LLNL physicist.

    “In spite of our intentions, Elis and I were floored when, at the X-ray beamline [Advanced Photon Source, beamline GSECARS.], a clear signature of a reaction between iron and nickel with xenon was signaled by the diffraction pattern,” added LLNL physical chemist Joe Zaug.

    ANL/APS

    Heavy NGEs like xenon are known to react with strong electronegative elements, such as halogens; however, as Stavrou added: “This is the first experimental evidence of a noble gas element reacting with a metal.”

    If this discovery were not enough, a transformative process was found to attribute the process where xenon reacted with metallic elements. Calculations by UoS and GL theorists Yansun Yao and Hanyu Liu revealed that at these conditions, iron and nickel metals become extraordinarily electronegative and attracted electrons away from xenon.

    “Amazing,” Zaug said, “The metals effectively became halogen-like under the Earth-core conditions we created in the laboratory.”

    The results indicate the changing chemical properties of elements under extreme conditions where elements, which are electropositive at ambient conditions, become electronegative. “A novel periodic table is needed to understand the changing chemical properties of elements under extreme thermodynamic conditions. There are many more systems and paradoxes to resolve. We look forward to writing new chapters about extreme physicochemical phenomena,” Stavrou said.

    Researchers contributing to the work include Yansun Yao of University of Saskatchewan, Alexander Goncharov, Sergey Lobanov and Hanyu Liu of Geophysical Laboratory and Vitali Prakapenka and Eran Greenberg of the Advanced Photon Source/ University of Chicago.

    This work was partially funded by a Laboratory Directed Research and Development Program project.

    See the full article here .

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  • richardmitnick 1:09 pm on February 8, 2018 Permalink | Reply
    Tags: , , Hayward fault earthquake simulations increase fidelity of ground motions, LLNL, ,   

    From LLNL: “Hayward fault earthquake simulations increase fidelity of ground motions” 


    Lawrence Livermore National Laboratory

    Feb. 8, 2018
    Anne M Stark
    stark8@llnl.gov (link sends e-mail)
    925-422-9799


    What will happen during an earthquake?

    In the next 30 years, there is a one-in-three chance that the Hayward fault will rupture with a 6.7 magnitude or higher earthquake, according to the United States Geologic Survey (USGS). Such an earthquake will cause widespread damage to structures, transportation and utilities, as well as economic and social disruption in the East Bay.

    Lawrence Livermore (LLNL) and Lawrence Berkeley (LBNL) national laboratory scientists have used some of the world’s most powerful supercomputers to model ground shaking for a magnitude (M) 7.0 earthquake on the Hayward fault and show more realistic motions than ever before. The research appears in Geophysical Research Letters.

    Past simulations resolved ground motions from low frequencies up to 0.5-1 Hertz (vibrations per second). The new simulations are resolved up to 4-5 Hertz (Hz), representing a four to eight times increase in the resolved frequencies. Motions with these frequencies can be used to evaluate how buildings respond to shaking.

    The simulations rely on the LLNL-developed SW4 seismic simulation program and the current best representation of the three-dimensional (3D) earth (geology and surface topography from the USGS) to compute seismic wave ground shaking throughout the San Francisco Bay Area. The results are, on average, consistent with models based on actual recorded earthquake motions from around the world.

    “This study shows that powerful supercomputing can be used to calculate earthquake shaking on a large, regional scale with more realism than we’ve ever been able to produce before,” said Artie Rodgers, LLNL seismologist and lead author of the paper.

    The Hayward fault is a major strike-slip fault on the eastern side of the Bay Area. This fault is capable of M 7 earthquakes and presents significant ground motion hazard to the heavily populated East Bay, including the cities of Oakland, Berkeley, Hayward and Fremont. The last major rupture occured in 1868 with an M 6.8-7.0 event. Instrumental observations of this earthquake were not available at the time. However, historical reports from the few thousand people who lived in the East Bay at the time indicate major damage to structures.

    The recent study reports ground motions simulated for a so-called scenario earthquake, one of many possibilities.

    “We’re not expecting to forecast the specifics of shaking from a future M 7 Hayward fault earthquake, but this study demonstrates that fully deterministic 3D simulations with frequencies up to 4 Hz are now possible. We get good agreement with ground motion models derived from actual recordings and we can investigate the impact of source, path and site effects on ground motions,” Rodgers said.

    As these simulations become easier with improvements in SW4 and computing power, the team will sample a range of possible ruptures and investigate how motions vary. The team also is working on improvements to SW4 that will enable simulations to 8-10 Hz for even more realistic motions.

    For residents of the East Bay, the simulations specifically show stronger ground motions on the eastern side of the fault (Orinda, Moraga) compared to the western side (Berkeley, Oakland). This results from different geologic materials — deep weaker sedimentary rocks that form the East Bay Hills. Evaluation and improvement of the 3D earth model is the subject of current research, for example using the Jan. 4, 2018 M 4.4 Berkeley earthquake that was widely felt around the northern Hayward fault.

    Ground motion simulations of large earthquakes are gaining acceptance as computational methods improve, computing resources become more powerful and representations of 3D earth structure and earthquake sources become more realistic.

    Rodgers adds: “It’s essential to demonstrate that high-performance computing simulations can generate realistic results and our team will work with engineers to evaluate the computed motions, so they can be used to understand the resulting distribution of risk to infrastructure and ultimately to design safer energy systems, buildlings and other infrastructure.”

    Other Livermore authors include seismologist Arben Pitarka, mathematicians Anders Petersson and Bjorn Sjogreen, along with project leader and structural engineer David McCallen of the University of California Office of the President and LBNL.

    This work is part of the DOE’s Exascale Computing Project (ECP (link is external)). The ECP is focused on accelerating the delivery of a capable exascale computing ecosystem that delivers 50 times more computational science and data analytic application power than possible with DOE HPC systems such as Titan (ORNL) and Sequoia (LLNL), with the goal to launch a U.S. exascale ecosystem by 2021.

    ORNL Cray XK7 Titan Supercomputer

    LLNL Sequoia IBM Blue Gene Q petascale supercomputer

    The ECP is a collaborative effort of two Department of Energy organizations — the DOE Office of Science and the National Nuclear Security Administration (link is external).

    Simulations were performed using a Computing Grand Challenge allocation on the Quartz supercomputer at LLNL and with an Exascale Computing Project allocation on Cori Phase-2 at the National Energy Research Scientific Computing Center (NERSC) at LBNL.

    See the full article here .

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    1

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

    YOU CAN HELP CATCH EARTHQUAKES AS THEY HAPPEN RIGHT NOW

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    BOINCLarge

    BOINC WallPaper

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

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  • richardmitnick 7:06 am on February 7, 2018 Permalink | Reply
    Tags: , First experimental evidence for superionic ice, LLNL, , , U Rochester's Laboratory for Laser Energetics, Uranus and Neptune might contain vast amount of superionic water ice   

    From LLNL: “First experimental evidence for superionic ice” 


    Lawrence Livermore National Laboratory

    Feb. 5, 2018
    Breanna Bishop
    bishop33@llnl.gov
    925-423-9802

    1
    Time-integrated image of a laser-driven shock compression experiment to recreate planetary interior conditions and study the properties of superionic water. Image by M. Millot/E. Kowaluk/J.Wickboldt/LLNL/LLE/NIF

    U Rochester’s Laboratory for Laser Energetics

    LLNL/NIF

    Among the many discoveries on matter at high pressure that garnered him the Nobel Prize in 1946, scientist Percy Bridgman discovered five different crystalline forms of water ice, ushering in more than 100 years of research into how ice behaves under extreme conditions.

    One of the most intriguing properties of water is that it may become superionic when heated to several thousand degrees at high pressure, similar to the conditions inside giant planets like Uranus and Neptune. This exotic state of water is characterized by liquid-like hydrogen ions moving within a solid lattice of oxygen.

    Since this was first predicted in 1988, many research groups in the field have confirmed and refined numerical simulations, while others used static compression techniques to explore the phase diagram of water at high pressure. While indirect signatures were observed, no research group has been able to identify experimental evidence for superionic water ice — until now.

    In a paper published today by Nature Physics , a research team from Lawrence Livermore National Laboratory (LLNL), the University of California, Berkeley and the University of Rochester provides experimental evidence for superionic conduction in water ice at planetary interior conditions, verifying the 30-year-old prediction.

    Using shock compression, the team identified thermodynamic signatures showing that ice melts near 5000 Kelvin (K) at 200 gigapascals (GPa — 2 million times Earth’s atmosphere) — 4000 K higher than the melting point at 0.5 megabar (Mbar) and almost the surface temperature of the sun.

    “Our experiments have verified the two main predictions for superionic ice: very high protonic/ionic conductivity within the solid and high melting point,” said lead author Marius Millot, a physicist at LLNL. “Our work provides experimental evidence for superionic ice and shows that these predictions were not due to artifacts in the simulations, but actually captured the extraordinary behavior of water at those conditions. This provides an important validation of state-of-the-art quantum simulations using density-functional-theory-based molecular dynamics (DFT-MD).”

    “Driven by the increase in computing resources available, I feel we have reached a turning point,” added Sebastien Hamel, LLNL physicist and co-author of the paper. “We are now at a stage where a large enough number of these simulations can be run to map out large parts of the phase diagram of materials under extreme conditions in sufficient detail to effectively support experimental efforts.”

    2
    Visualization of molecular dynamics simulations showing the fast diffusion of hydrogen ions (pink trajectories) within the solid lattice of oxygen in superionic ice. Image by S. Hamel/M. Millot/J.Wickboldt/LLNL/NIF

    Using diamond anvil cells (DAC), the team applied 2.5 GPa of pressure (25 thousand atmospheres) to pre-compress water into the room-temperature ice VII, a cubic crystalline form that is different from “ice-cube” hexagonal ice, in addition to being 60 percent denser than water at ambient pressure and temperature. They then shifted to the University of Rochester’s Laboratory for Laser Energetics (LLE) to perform laser-driven shock compression of the pre-compressed cells. They focused up to six intense beams of LLE’s Omega-60 laser, delivering a 1 nanosecond pulse of UV light onto one of the diamonds. This launched strong shock waves of several hundred GPa into the sample, to compress and heat the water ice at the same time.

    “Because we pre-compressed the water, there is less shock-heating than if we shock-compressed ambient liquid water, allowing us to access much colder states at high pressure than in previous shock compression studies, so that we could reach the predicted stability domain of superionic ice,” Millot said.

    The team used interferometric ultrafast velocimetry and pyrometry to characterize the optical properties of the shocked compressed water and determine its thermodynamic properties during the brief 10-20 nanosecond duration of the experiment, before pressure release waves decompressed the sample and vaporized the diamonds and the water.

    “These are very challenging experiments, so it was really exciting to see that we could learn so much from the data — especially since we spent about two years making the measurements and two more years developing the methods to analyze the data,” Millot said.

    This work also has important implications for planetary science because Uranus and Neptune might contain vast amount of superionic water ice. Planetary scientists believe these giant planets are made primarily of a carbon, hydrogen, oxygen and nitrogen (C-H-O-N) mixture that corresponds to 65 percent water by mass, mixed with ammonia and methane.

    Many scientists envision these planets with fully fluid convecting interiors. Now, the experimental discovery of superionic ice should give more strength to a new picture for these objects with a relatively thin layer of fluid and a large “mantle” of superionic ice. In fact, such a structure was proposed a decade ago — based on dynamo simulation — to explain the unusual magnetic fields of these planets. This is particularly relevant as NASA is considering launching a probe to Uranus and/or Neptune, in the footsteps of the successful Cassini and Juno missions to Saturn and Jupiter.

    “Magnetic fields provide crucial information about the interiors and evolution of planets, so it is gratifying that our experiments can test — and in fact, support — the thin-dynamo idea that had been proposed for explaining the truly strange magnetic fields of Uranus and Neptune,” said Raymond Jeanloz, co-author on the paper and professor in Earth & Planetary Physics and Astronomy at the University of California, Berkeley. It’s also mind-boggling that frozen water ice is present at thousands of degrees inside these planets, but that’s what the experiments show.”

    “The next step will be to determine the structure of the oxygen lattice,” said Federica Coppari, LLNL physicist and co-author of the paper. “X-ray diffraction is now routinely performed in laser-shock experiments at Omega and it will allow to determine experimentally the crystalline structure of superionic water. This would be very exciting because theoretical simulations struggle to predict the actual structure of superionic water ice.”

    Looking ahead, the team plans to push to higher pre-compression and extend the technique to other materials, such as helium, that would be more representative of planets like Saturn and Jupiter.

    Co-authors include Hamel, Peter Celliers, Coppari, Dayne Fratanduono, Damian Swift and Jon Eggert from LLNL; Jeanloz from UC Berkeley; and Ryan Rygg and Gilbert Collins, previously at LLNL and now at the University of Rochester. The experiments also were supported by target fabrication efforts by LLNL’s Stephanie Uhlich, Antonio Correa Barrios, Carol Davis, Jim Emig, Eric Folsom, Renee Posadas Soriano, Walter Unites and Timothy Uphaus.

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 4:27 pm on January 3, 2018 Permalink | Reply
    Tags: , , LLNL, , , TPL-two-photon lithography,   

    From LLNL: “Lab unlocks secrets of nanoscale 3D printing” 


    Lawrence Livermore National Laboratory

    Jan. 3, 2018
    Jeremy Thomas
    thomas244@llnl.gov
    925-422-5539

    1
    Through the two-photon lithography (TPL) 3D printing process, researchers can print woodpile lattices with submicron features a fraction of the width of a human hair. Image by Jacob Long and Adam Connell/LLNL.

    Lawrence Livermore National Laboratory (LLNL) researchers have discovered novel ways to extend the capabilities of two-photon lithography (TPL), a high-resolution 3D printing technique capable of producing nanoscale features smaller than one-hundredth the width of a human hair.

    The findings, recently published on the cover of the journal ACS Applied Materials & Interfaces , also unleashes the potential for X-ray computed tomography (CT) to analyze stress or defects noninvasively in embedded 3D-printed medical devices or implants.

    Two-photon lithography typically requires a thin glass slide, a lens and an immersion oil to help the laser light focus to a fine point where curing and printing occurs. It differs from other 3D-printing methods in resolution, because it can produce features smaller than the laser light spot, a scale no other printing process can match. The technique bypasses the usual diffraction limit of other methods because the photoresist material that cures and hardens to create structures — previously a trade secret — simultaneously absorbs two photons instead of one.

    2
    LLNL researchers printed octet truss structures with submicron features on top of a solid base with a diameter similar to human hair. Photo by James Oakdale/LLNL.

    In the paper, LLNL researchers describe cracking the code on resist materials optimized for two-photon lithography and forming 3D microstructures with features less than 150 nanometers. Previous techniques built structures from the ground up, limiting the height of objects because the distance between the glass slide and lens is usually 200 microns or less. By turning the process on its head — putting the resist material directly on the lens and focusing the laser through the resist — researchers can now print objects multiple millimeters in height. Furthermore, researchers were able to tune and increase the amount of X-rays the photopolymer resists could absorb, improving attenuation by more than 10 times over the photoresists commonly used for the technique.

    “In this paper, we have unlocked the secrets to making custom materials on two-photon lithography systems without losing resolution,” said LLNL researcher James Oakdale, a co-author on the paper.

    Because the laser light refracts as it passes through the photoresist material, the linchpin to solving the puzzle, the researchers said, was “index matching” – discovering how to match the refractive index of the resist material to the immersion medium of the lens so the laser could pass through unimpeded. Index matching opens the possibility of printing larger parts, they said, with features as small as 100 nanometers.

    “Most researchers who want to use two-photon lithography for printing functional 3D structures want parts taller than 100 microns,” said Sourabh Saha, the paper’s lead author. “With these index-matched resists, you can print structures as tall as you want. The only limitation is the speed. It’s a tradeoff, but now that we know how to do this, we can diagnose and improve the process.”

    3
    Through the two-photon lithography (TPL) 3D printing process, researchers can print woodpile lattices with submicron features a fraction of the width of a human hair. Photo by James Oakdale/LLNL.

    By tuning the material’s X-ray absorption, researchers can now use X-ray-computed tomography as a diagnostic tool to image the inside of parts without cutting them open or to investigate 3D-printed objects embedded inside the body, such as stents, joint replacements or bone scaffolds. These techniques also could be used to produce and probe the internal structure of targets for the National Ignition Facility, as well as optical and mechanical metamaterials and 3D-printed electrochemical batteries.

    The only limiting factor is the time it takes to build, so researchers will next look to parallelize and speed up the process. They intend to move into even smaller features and add more functionality in the future, using the technique to build real, mission-critical parts.

    “It’s a very small piece of the puzzle that we solved, but we are much more confident in our abilities to start playing in this field now,” Saha said. “We’re on a path where we know we have a potential solution for different types of applications. Our push for smaller and smaller features in larger and larger structures is bringing us closer to the forefront of scientific research that the rest of the world is doing. And on the application side, we’re developing new practical ways of printing things.”

    The work was funded through the Laboratory Directed Research and Development (LDRD) program. Other LLNL researchers who contributed to the project include Jefferson Cuadra, Chuck Divin, Jianchao Ye, Jean-Baptiste Forien, Leonardus Bayu Aji, Juergen Biener and Will Smith.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    LLNL Campus

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

     
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