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  • richardmitnick 7:56 am on July 2, 2019 Permalink | Reply
    Tags: , , Fusion technology,   

    From PPPL: “Artificial intelligence accelerates efforts to develop clean, virtually limitless fusion energy” 

    From PPPL

    April 17, 2019 [Just found this in social media]
    John Greenwald

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    Depiction of fusion research on a doughnut-shaped tokamak enhanced by artificial intelligence. (Depiction by Eliot Feibush/PPPL and Julian Kates-Harbeck/Harvard University)

    Artificial intelligence (AI), a branch of computer science that is transforming scientific inquiry and industry, could now speed the development of safe, clean and virtually limitless fusion energy for generating electricity. A major step in this direction is under way at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University, where a team of scientists working with a Harvard graduate student is for the first time applying deep learning — a powerful new version of the machine learning form of AI — to forecast sudden disruptions that can halt fusion reactions and damage the doughnut-shaped tokamaks that house the reactions.

    Promising new chapter in fusion research

    “This research opens a promising new chapter in the effort to bring unlimited energy to Earth,” Steve Cowley, director of PPPL, said of the findings, which are reported in the current issue of Nature magazine. “Artificial intelligence is exploding across the sciences and now it’s beginning to contribute to the worldwide quest for fusion power.”

    Fusion, which drives the sun and stars, is the fusing of light elements in the form of plasma — the hot, charged state of matter composed of free electrons and atomic nuclei — that generates energy. Scientists are seeking to replicate fusion on Earth for an abundant supply of power for the production of electricity.

    Crucial to demonstrating the ability of deep learning to forecast disruptions — the sudden loss of confinement of plasma particles and energy — has been access to huge databases provided by two major fusion facilities: the DIII-D National Fusion Facility that General Atomics operates for the DOE in California, the largest facility in the United States, and the Joint European Torus (JET) in the United Kingdom, the largest facility in the world, which is managed by EUROfusion, the European Consortium for the Development of Fusion Energy. Support from scientists at JET and DIII-D has been essential for this work.

    DOE DIII-D Tokamak

    Joint European Torus, at the Culham Centre for Fusion Energy in the United Kingdom

    The vast databases have enabled reliable predictions of disruptions on tokamaks other than those on which the system was trained — in this case from the smaller DIII-D to the larger JET. The achievement bodes well for the prediction of disruptions on ITER, a far larger and more powerful tokamak that will have to apply capabilities learned on today’s fusion facilities.


    ITER Tokamak in Saint-Paul-lès-Durance, which is in southern France

    The deep learning code, called the Fusion Recurrent Neural Network (FRNN), also opens possible pathways for controlling as well as predicting disruptions.

    Most intriguing area of scientific growth

    “Artificial intelligence is the most intriguing area of scientific growth right now, and to marry it to fusion science is very exciting,” said Bill Tang, a principal research physicist at PPPL, coauthor of the paper and lecturer with the rank and title of professor in the Princeton University Department of Astrophysical Sciences who supervises the AI project. “We’ve accelerated the ability to predict with high accuracy the most dangerous challenge to clean fusion energy.”

    Unlike traditional software, which carries out prescribed instructions, deep learning learns from its mistakes. Accomplishing this seeming magic are neural networks, layers of interconnected nodes — mathematical algorithms — that are “parameterized,” or weighted by the program to shape the desired output. For any given input the nodes seek to produce a specified output, such as correct identification of a face or accurate forecasts of a disruption. Training kicks in when a node fails to achieve this task: the weights automatically adjust themselves for fresh data until the correct output is obtained.

    A key feature of deep learning is its ability to capture high-dimensional rather than one-dimensional data. For example, while non-deep learning software might consider the temperature of a plasma at a single point in time, the FRNN considers profiles of the temperature developing in time and space. “The ability of deep learning methods to learn from such complex data make them an ideal candidate for the task of disruption prediction,” said collaborator Julian Kates-Harbeck, a physics graduate student at Harvard University and a DOE-Office of Science Computational Science Graduate Fellow who was lead author of the Nature paper and chief architect of the code.

    Training and running neural networks relies on graphics processing units (GPUs), computer chips first designed to render 3D images. Such chips are ideally suited for running deep learning applications and are widely used by companies to produce AI capabilities such as understanding spoken language and observing road conditions by self-driving cars.

    Kates-Harbeck trained the FRNN code on more than two terabytes (1012) of data collected from JET and DIII-D. After running the software on Princeton University’s Tiger cluster of modern GPUs, the team placed it on Titan, a supercomputer at the Oak Ridge Leadership Computing Facility, a DOE Office of Science User Facility, and other high-performance machines.

    Tiger Dell Linux supercomputer at Princeton University

    ORNL Cray XK7 Titan Supercomputer, once the fastest in the world, now No.9 on the TOP500

    A demanding task

    Distributing the network across many computers was a demanding task. “Training deep neural networks is a computationally intensive problem that requires the engagement of high-performance computing clusters,” said Alexey Svyatkovskiy, a coauthor of the Nature paper who helped convert the algorithms into a production code and now is at Microsoft. “We put a copy of our entire neural network across many processors to achieve highly efficient parallel processing,” he said.

    The software further demonstrated its ability to predict true disruptions within the 30-millisecond time frame that ITER will require, while reducing the number of false alarms. The code now is closing in on the ITER requirement of 95 percent correct predictions with fewer than 3 percent false alarms. While the researchers say that only live experimental operation can demonstrate the merits of any predictive method, their paper notes that the large archival databases used in the predictions, “cover a wide range of operational scenarios and thus provide significant evidence as to the relative strengths of the methods considered in this paper.”

    From prediction to control

    The next step will be to move from prediction to the control of disruptions. “Rather than predicting disruptions at the last moment and then mitigating them, we would ideally use future deep learning models to gently steer the plasma away from regions of instability with the goal of avoiding most disruptions in the first place,” Kates-Harbeck said. Highlighting this next step is Michael Zarnstorff, who recently moved from deputy director for research at PPPL to chief science officer for the laboratory. “Control will be essential for post-ITER tokamaks – in which disruption avoidance will be an essential requirement,” Zarnstorff noted.

    Progressing from AI-enabled accurate predictions to realistic plasma control will require more than one discipline. “We will combine deep learning with basic, first-principle physics on high-performance computers to zero in on realistic control mechanisms in burning plasmas,” said Tang. “By control, one means knowing which ‘knobs to turn’ on a tokamak to change conditions to prevent disruptions. That’s in our sights and it’s where we are heading.”

    Support for this work comes from the Department of Energy Computational Science Graduate Fellowship Program of the DOE Office of Science and National Nuclear Security Administration; from Princeton University’s Institute for Computational Science and Engineering (PICsiE); and from Laboratory Directed Research and Development funds that PPPL provides. The authors wish to acknowledge assistance with high-performance supercomputing from Bill Wichser and Curt Hillegas at PICSciE; Jack Wells at the Oak Ridge Leadership Computing Facility; Satoshi Matsuoka and Rio Yokata at the Tokyo Institute of Technology; and Tom Gibbs at NVIDIA Corp.

    See the full article here .


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    PPPL campus

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University. PPPL, on Princeton University’s Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas — ultra-hot, charged gases — and to developing practical solutions for the creation of fusion energy. Results of PPPL research have ranged from a portable nuclear materials detector for anti-terrorist use to universally employed computer codes for analyzing and predicting the outcome of fusion experiments. The Laboratory is managed by the University for the U.S. Department of Energy’s Office of Science, which is the largest single supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

     
  • richardmitnick 10:12 am on June 5, 2019 Permalink | Reply
    Tags: Fusion technology, INFUSE-Innovation Network for Fusion Energy program, ,   

    From Oak Ridge National Laboratory: “New DOE program connects fusion companies with national labs, taps ORNL to lead” 

    i1

    From Oak Ridge National Laboratory

    June 4, 2019

    The Department of Energy has established the Innovation Network for Fusion Energy program, or INFUSE, to encourage private-public research partnerships for overcoming challenges in fusion energy development.

    The program, sponsored by the Office of Fusion Energy Sciences (FES) within DOE’s Office of Science, focuses on accelerating fusion energy development through research collaborations between industry and DOE’s national laboratory complex with its scientific expertise and facilities. The program is currently soliciting proposals and plans to select a number of projects for awards between $50,000 and $200,000 each, with a 20 percent project cost share for industry partners.

    “We believe there is a real potential for synergy between industry- and government-sponsored research efforts in fusion,” said James Van Dam, DOE Associate Director of Science for Fusion Energy Sciences. “This innovative program will advance progress toward fusion energy by drawing on the combined expertise of researchers from both sectors.”

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    DOE’s Oak Ridge National Laboratory (ORNL) will manage the new program with Princeton Plasma Physics Laboratory (PPPL).

    ORNL’s Dennis Youchison, a fusion engineer with extensive experience in plasma facing components, will serve as the director, and PPPL’s Ahmed Diallo, a physicist with expertise in laser diagnostics, will serve as deputy director.

    “I am excited about the potential of INFUSE and believe this step will instill a new vitality to the entire fusion community,” Youchison said. “With growing interest in developing cost-effective sources of fusion energy, INFUSE will help focus current research. Multiple private companies in the United States are pursuing fusion energy systems, and we want to contribute scientific solutions that help make fusion a reality.”

    Through INFUSE, companies can gain access to DOE’s world-leading facilities and researchers for tackling basic research challenges in developing fusion energy systems.

    INFUSE will help address enabling technologies, such as new and improved magnets; materials science, including engineered materials, testing and qualification; plasma diagnostic development; modeling and simulation; and magnetic fusion experimental capabilities.

    “These are core competencies across our national laboratories and areas where industry needs support,” Youchison said. “We have unique capabilities not found in the private sector, and this program will help lower barriers to collaboration and move fusion energy forward.”

    ORNL’s program management leverages its long-standing leadership in fusion science. The lab is home to the US ITER Project Office and employs scientists and engineers with expertise in plasma experimentation, blanket and fuel cycle research, materials development and computer modeling of fusion systems.

    ORNL is also home to key facilities for the development of fueling and disruption mitigation solutions.

    “When you look at nuclear science as a whole, ORNL has been a global leader for more than 75 years. Today, we have a site that allows for new and groundbreaking nuclear fusion experiments and resources that are not found anywhere else in the world,” Youchison said. “We can deliver impactful research to help in the pursuit of fusion energy deployment.”

    ORNL and PPPL are joined by Pacific Northwest, Idaho, Brookhaven, Lawrence Berkeley, Los Alamos and Lawrence Livermore national laboratories as participants in the INFUSE program. Proposal submissions are due June 30, and award notifications are expected August 10.

    See the full article here .


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    ORNL is managed by UT-Battelle for the Department of Energy’s Office of Science. DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time.

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  • richardmitnick 1:03 pm on May 19, 2019 Permalink | Reply
    Tags: , Fusion technology, , , Reversing traditional plasma shaping provides greater stability for fusion reactions.   

    From MIT News: “Steering fusion’s ‘D-turn'” 

    MIT News

    From MIT News

    May 17, 2019
    Paul Rivenberg | Plasma Science and Fusion Center

    1
    Cross sections of pressure profiles are shown in two different tokamak plasma configurations (the center of the tokamak doughnut is to the left of these). The discharges have high pressure in the core (yellow) that decreases to low pressure (blue) at the edge. Researchers achieved substantial high-pressure operation of reverse-D plasmas at the DIII-D National Fusion Facility.

    Image: Alessandro Marinoni/MIT PSFC

    Research scientist Alessandro Marinoni shows that reversing traditional plasma shaping provides greater stability for fusion reactions.

    Trying to duplicate the power of the sun for energy production on earth has challenged fusion researchers for decades. One path to endless carbon-free energy has focused on heating and confining plasma fuel in tokamaks, which use magnetic fields to keep the turbulent plasma circulating within a doughnut-shaped vacuum chamber and away from the walls. Fusion researchers have favored contouring these tokamak plasmas into a triangular or D shape, with the curvature of the D stretching away from the center of the doughnut, which allows plasma to withstand the intense pressures inside the device better than a circular shape.

    Led by research scientists Alessandro Marinoni of MIT’s Plasma Science and Fusion Center (PSFC) and Max Austin, of the University of Texas at Austin, researchers at the DIII-D National Fusion Facility have discovered promising evidence that reversing the conventional shape of the plasma in the tokamak chamber can create a more stable environment for fusion to occur, even under high pressure. The results were recently published in Physical Review Letters and Physics of Plasmas.

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    DIII-D National Fusion Facility. General Atomics

    Marinoni first experimented with the “reverse-D” shape, also known as “negative triangularity,” while pursuing his PhD on the TCV tokamak at Ecole Polytechnique Fédérale de Lausanne, Switzerland.

    4
    The Tokamak à configuration variable (TCV, literally “variable configuration tokamak”) is a Swiss research fusion reactor of the École polytechnique fédérale de Lausanne. Its distinguishing feature over other tokamaks is that its torus section is three times higher than wide. This allows studying several shapes of plasmas, which is particularly relevant since the shape of the plasma has links to the performance of the reactor. The TCV was set up in November 1992.

    The TCV team was able to show that negative triangularity helps to reduce plasma turbulence, thus increasing confinement, a key to sustaining fusion reactions.

    “Unfortunately, at that time, TCV was not equipped to operate at high plasma pressures with the ion temperature being close to that of electrons,” notes Marinoni, “so we couldn’t investigate regimes that are directly relevant to fusion plasma conditions.”

    Growing up outside Milan, Marinoni developed an interest in fusion through an early passion for astrophysical phenomena, hooked in preschool by the compelling mysteries of black holes.

    “It was fascinating because black holes can trap light. At that time I was just a little kid. As such, I couldn’t figure out why the light could be trapped by the gravitational force exerted by black holes, given that on Earth nothing like that ever happens.”

    As he matured he joined a local amateur astronomy club, but eventually decided black holes would be a hobby, not his vocation.

    “My job would be to try producing energy through nuclear fission or fusion; that’s the reason why I enrolled in the nuclear engineering program in the Polytechnic University of Milan.”

    After studies in Italy and Switzerland, Marinoni seized the opportunity to join the PSFC’s collaboration with the DIII-D tokamak in San Diego, under the direction of MIT professor of physics Miklos Porkolab. As a postdoc, he used MIT’s phase contrast imaging diagnostic to measure plasma density fluctuations in DIII-D, later continuing work there as a PSFC research scientist.

    Max Austin, after reading the negative triangularity results from TCV, decided to explore the possibility of running similar experiments on the DIII-D tokamak to confirm the stabilizing effect of negative triangularity. For the experimental proposal, Austin teamed up with Marinoni and together they designed and carried out the experiments.

    “The DIII-D research team was working against decades-old assumptions,” says Marinoni. “It was generally believed that plasmas at negative triangularity could not hold high enough plasma pressures to be relevant for energy production, because of macroscopic scale Magneto-Hydro-Dynamics (MHD) instabilities that would arise and destroy the plasma. MHD is a theory that governs the macro-stability of electrically conducting fluids such as plasmas. We wanted to show that under the right conditions the reverse-D shape could sustain MHD stable plasmas at high enough pressures to be suitable for a fusion power plant, in some respects even better than a D-shape.”

    While D-shaped plasmas are the standard configuration, they have their own challenges. They are affected by high levels of turbulence, which hinders them from achieving the high pressure levels necessary for economic fusion. Researchers have solved this problem by creating a narrow layer near the plasma boundary where turbulence is suppressed by large flow shear, thus allowing inner regions to attain higher pressure. In the process, however, a steep pressure gradient develops in the outer plasma layers, making the plasma susceptible to instabilities called edge localized modes that, if sufficiently powerful, would expel a substantial fraction of the built-up plasma energy, thus damaging the tokamak chamber walls.

    DIII-D was designed for the challenges of creating D-shaped plasmas. Marinoni praises the DIII-D control group for “working hard to figure out a way to run this unusual reverse-D shape plasma.”

    The effort paid off. DIII-D researchers were able to show that even at higher pressures, the reverse-D shape is as effective at reducing turbulence in the plasma core as it was in the low-pressure TCV environment. Despite previous assumptions, DIII-D demonstrated that plasmas at reversed triangularity can sustain pressure levels suitable for a tokamak-based fusion power plant; additionally, they can do so without the need to create a steep pressure gradient near the edge that would lead to machine-damaging edge localized modes.

    Marinoni and colleagues are planning future experiments to further demonstrate the potential of this approach in an even more fusion-power relevant magnetic topology, based on a “diverted” tokamak concept. He has tried to interest other international tokamaks in experimenting with the reverse configuration.

    “Because of hardware issues, only a few tokamaks can create negative triangularity plasmas; tokamaks like DIII-D, that are not designed to produce plasmas at negative triangularity, need a significant effort to produce this plasma shape. Nonetheless, it is important to engage the fusion community worldwide to more fully establish the data base on the benefits of this shape.”

    Marinoni looks forward to where the research will take the DIII-D team. He looks back to his introduction to tokamak, which has become the focus of his research.

    “When I first learned about tokamaks I thought, ‘Oh, cool! It’s important to develop a new source of energy that is carbon free!’ That is how I ended up in fusion.”

    This research is sponsored by the U.S. Department of Energy Office of Science’s Fusion Energy Sciences, using their DIII-D National Fusion Facility.

    See the full article here .


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  • richardmitnick 10:27 am on May 7, 2019 Permalink | Reply
    Tags: , , Fusion technology, , , , , , TRC- Translational Research Capability   

    From Oak Ridge National Laboratory: “New research facility will serve ORNL’s growing mission in computing, materials R&D” 

    i1

    From Oak Ridge National Laboratory

    May 7, 2019
    Bill H Cabage
    cabagewh@ornl.gov
    865-574-4399

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    Pictured in this early conceptual drawing, the Translational Research Capability planned for Oak Ridge National Laboratory will follow the design of research facilities constructed during the laboratory’s modernization campaign.

    Energy Secretary Rick Perry, Congressman Chuck Fleischmann and lab officials today broke ground on a multipurpose research facility that will provide state-of-the-art laboratory space for expanding scientific activities at the Department of Energy’s Oak Ridge National Laboratory.

    The new Translational Research Capability, or TRC, will be purpose-built for world-leading research in computing and materials science and will serve to advance the science and engineering of quantum information.

    “Through today’s groundbreaking, we’re writing a new chapter in research at the Translational Research Capability Facility,” said U.S. Secretary of Energy Rick Perry. “This building will be the home for advances in Quantum Information Science, battery and energy storage, materials science, and many more. It will also be a place for our scientists, researchers, engineers, and innovators to take on big challenges and deliver transformative solutions.”

    With an estimated total project cost of $95 million, the TRC, located in the central ORNL campus, will accommodate sensitive equipment, multipurpose labs, heavy equipment and inert environment labs. Approximately 75 percent of the facility will contain large, modularly planned and open laboratory areas with the rest as office and support spaces.

    “This research and development space will advance and support the multidisciplinary mission needs of the nation’s advanced computing, materials research, fusion science and physics programs,” ORNL Director Thomas Zacharia said. “The new building represents a renaissance in the way we carry out research allowing more flexible alignment of our research activities to the needs of frontier research.”

    The flexible space will support the lab’s growing fundamental materials research to advance future quantum information science and computing systems. The modern facility will provide atomic fabrication and materials characterization capabilities to accelerate the development of novel quantum computing devices. Researchers will also use the facility to pursue advances in quantum modeling and simulation, leveraging a co-design approach to develop algorithms along with prototype quantum systems.

    The new laboratories will provide noise isolation, electromagnetic shielding and low vibration environments required for multidisciplinary research in quantum information science as well as materials development and performance testing for fusion energy applications. The co-location of the flexible, modular spaces will enhance collaboration among projects.

    At approximately 100,000 square feet, the TRC will be similar in size and appearance to another modern ORNL research facility, the Chemical and Materials Sciences Building, which was completed in 2011 and is located nearby.

    The facility’s design and location will also conform to sustainable building practices with an eye toward encouraging collaboration among researchers. The TRC will be centrally located in the ORNL main campus area on a brownfield tract that was formerly occupied by one of the laboratory’s earliest, Manhattan Project-era structures.

    ORNL began a modernization campaign shortly after UT-Battelle arrived in 2000 to manage the national laboratory. The new construction has enabled the laboratory to meet growing space and infrastructure requirements for rapidly advancing fields such as scientific computing while vacating legacy spaces with inherent high operating costs, inflexible infrastructure and legacy waste issues.

    The construction is supported by the Science Laboratory Infrastructure program of the DOE Office of Science.

    See the full article here .


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  • richardmitnick 9:12 am on April 17, 2019 Permalink | Reply
    Tags: , Fusion technology, , , , Z-pinch   

    From University of Washington via Science Alert: “Researchers Just Demonstrated Nuclear Fusion in a Device Small Enough to Keep at Home” 

    U Washington

    From University of Washington

    via

    ScienceAlert

    Science Alert

    17 APR 2019
    MIKE MCRAE

    1
    (Cappan/iStock)

    When it comes to the kinds of technology needed to contain a sun, there are currently just two horses in the race. Neither is what you’d call ‘petite’.

    An earlier form of fusion technology that barely made it out of the starting blocks has just overcome a serious hurdle. It’s got a long way to catch up, but given its potential cost and versatility, a table-sized fusion device like this is worth watching out for.

    While many have long given up on an early form of plasma confinement called the Z-pinch as a feasible way to generate power, researchers at the University of Washington in the US have continued to look for a way to overcome its shortcomings.

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    A laboratory scale z-pinch device in operation with a Hydrogen plasma. Sandpiper at English Wikipedia

    Fusion power relies on clouds of charged particles you can squeeze the literal daylights out of – it’s the reaction that powers that big ball of hot gas we call the Sun.

    But containing a buzzing mix of superhot ions is extremely challenging – in the lab, scientists use intense magnetic fields for this task. Tokamaks like China’s Experimental Advanced Superconducting Tokamak reactor swirl their insanely hot plasma in such a way that they generate their own internal magnetic fields, helping contain the flow.

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    China’s Experimental Advanced Superconducting Tokamak reactor (EAST)

    This approach gets the plasma cooking enough for it to release a critical amount of energy. But what it gains in generating heat it loses in long-term stability.

    Stellerators like Germany’s Wendelstein 7-X, on the other hand, rely more heavily on banks of externally applied magnetic fields. While this makes for better control over the plasma, it also makes it harder to reach the temperatures needed for fusion to occur.

    Wendelstein 7-AS built in built in Greifswald, Germany

    Both are making serious headway in our march towards fusion power. But those doughnuts holding the plasma are at least a few metres (a dozen feet) across, surrounded by complex banks of delicate electronics, making it unlikely we’ll see them shrink to a home or mobile version any time soon.

    In the early days of fusion research, a somewhat simpler method for squeezing a jet of plasma was to ‘pinch’ it through a magnetic field.

    A relatively small device known as a zeta or ‘Z’-pinch uses the specific orientation of a plasma’s internal magnetic field to apply what’s known as the Lorentz force to the flow of particles, effectively forcing its particles together through a bottleneck.

    In some sense, the device isn’t unlike a miniature version of its tokamak big brother. As such, it also suffers from similar stability issues that can cause its plasma to jump from the magnetic tracks and crash into the sides of its container.

    In fact, iterations of the Z-pinch led to the chunky tokamak technology that superseded it. Given this major limitation, the Z-pinch has all but become a relic of history.

    Hope remains that by going back to the roots of fusion, researchers might find a way to generate power without the need for complicated banks of surrounding machinery and magnets.

    Now, researchers from the University of Washington have found an alternative approach to stabilising the plasma in a Z-pinch not only works, but it can be used to generate a burst of fusion.

    To prevent the distortions in the plasma that cause it to escape the confines of its magnetic cage, the team manages the flow of the particles by applying a bit of fluid dynamics.

    Introducing what is known as sheared axial flow to a short column of plasma has previously been studied as a potential way to improve stability in a Z-pinch, to rather limited effect.

    Not to be deterred, physicists relied on computer simulations to show the concept was possible.

    Using a mix of 20 percent deuterium and 80 percent hydrogen, the team managed to hold stable a 50 centimetre (1.6 foot) long column of plasma enough to achieve fusion, evidenced by a signature generation of neutrons being emitted.

    We’re only talking 5 microseconds worth of neutrons here, so don’t clear space in your basement for your Z-Pinch 3000 Home Fusion Box quite yet. But the stability was 5,000 times longer than you’d expect without such a method being used, showing the principle is ripe for further study.

    Generating clean, abundant fusion energy is still a dream we’re all holding onto. A new approach to a less complex form of plasma technology could help remove at least some of the obstacles, if not prove to be a cheaper, more compact source of clean power in its own right.

    The race towards the horizon of limitless energy production is only just warming up, folks. And it really can’t come soon enough.

    This research was published in Physical Review Letters.

    See the full article here .


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  • richardmitnick 11:10 am on April 3, 2019 Permalink | Reply
    Tags: "Last-minute deal grants European money to U.K.-based fusion reactor", Culham Centre for Fusion Energy (CCFE)-home of JET, Fusion technology, ITER experimental tokamak nuclear fusion reactor, , The Joint European Torus tokamak-JET   

    From Science Magazine: “Last-minute deal grants European money to U.K.-based fusion reactor” 

    AAAS
    From Science Magazine

    Mar. 29, 2019
    Daniel Clery

    The Joint European Torus tokamak generator based at the Culham Center for Fusion Energy located at the Culham Science Centre, near Culham, Oxfordshire, England


    The walls of the Joint European Torus fusion reactor are lined with the same materials as ITER, a much larger fusion reactor under construction.
    ©EUROfusion (CC BY)

    ITER experimental tokamak nuclear fusion reactor that is being built next to the Cadarache facility in Saint Paul les-Durance south of France

    At the eleventh hour, the European Union has agreed to fund Europe’s premier fusion research facility in the United Kingdom—even if the United Kingdom leaves the European Union early next month. The decision to provide €100 million to keep the Joint European Torus (JET) running in 2019 and 2020 will come as a relief both to fusion researchers building the much larger ITER reactor near Cadarache in France and the 500 JET staff working in Culham, near Oxford, U.K.

    “Now we have some certainty over JET,” says Ian Chapman, director of the Culham Centre for Fusion Energy (CCFE), which hosts the JET. But the agreement does not guarantee the JET’s future beyond the end of next year, nor does it ensure that U.K. scientists will be able to participate in European fusion research programs.

    Until the $25 billion ITER is finished in 2025, the JET is the largest fusion reactor in the world. In 2011, the interior surface of its reactor vessel was relined with the same material ITER will use, tungsten and beryllium, making the JET the best simulator for understanding the behavior of its giant cousin.

    The JET was built in the 1970s and ’80s as part of Euratom, a European agreement governing nuclear research. In recent years, CCFE has been managing the JET on behalf of Euratom. But Brexit, the threat of the United Kingdom’s departure from the European Union, has clouded the reactor’s future. The U.K. government has said it also intends to withdraw from Euratom, a separate treaty than the one that governs the European Union. The U.K. government wishes to become an associate member of Euratom, a position that Switzerland holds, so it can continue to participate in research and training. But that agreement cannot be negotiated until after Brexit, which could come as soon as 12 April—or not. With the United Kingdom’s future relationship with Europe still a matter of heated debate, so is its partnership with Euratom.

    CCFE was contracted to manage the JET until the end of 2018. The agreement announced today keeps the JET running until the end of 2020 with €100 million from Euratom. “There is no Brexit clause,” Chapman says, so whatever happens in the coming weeks, the JET is safe for now.

    The JET is essential for ITER preparations, not just because of its inner wall, but because it is the only reactor in the world equipped to run with the same sort of fuel ITER will use, a mixture of deuterium and tritium, both isotopes of hydrogen. In 2020, researchers hope to study how this fuel behaves in the revamped the JET to make it easier to get ITER up to full performance. “It’s a really important experiment,” Chapman says. “We need to demonstrate that we can get a high-performance plasma with a tungsten-beryllium wall. It’s never been done with deuterium-tritium before.”

    Beyond 2020, the JET’s future is uncertain, even aside from Brexit. Euratom and ITER would both like to keep the JET running to carry out more studies up until 2024. Ultimately, that depends on it winning funding in the European Union’s next funding cycle, which begins in 2021. But a question still hangs over what sort of relationship the United Kingdom will have with Euratom by that time. “That uncertainty has not gone away,” Chapman says.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

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  • richardmitnick 2:43 pm on February 23, 2019 Permalink | Reply
    Tags: "14-Year-Old Kid Has Reportedly Become The Youngest Person to Achieve Nuclear Fusion", , , , Fusion technology, , The Open Source Fusor Research Consortium has also verified Oswalt's results   

    From Science Alert: “14-Year-Old Kid Has Reportedly Become The Youngest Person to Achieve Nuclear Fusion” 

    ScienceAlert

    From Science Alert

    22 FEB 2019
    CARLY CASSELLA

    1
    (Fox News)

    We might have a new contender for the youngest person to ever achieve nuclear fusion.

    Tennessee teenager Jackson Oswalt is not your average 14-year-old. While other kids are playing video games or watching TV, he’s been busy putting together a nuclear laboratory in an old playroom in his house.

    The budding nuclear engineer has been working on this project since he was 12, and on 19 January 2018, just hours before his 13th birthday, he reportedly achieved his mission.
    Using 50,000 volts of electricity, Oswalt was reportedly able to combine two atoms of deuterium gas, successfully fusing the nuclei in his reactor’s plasma core.

    2
    (Jackson Oswalt)

    After conducting some further tests over the following months, Oswalt became more convinced than ever that he had achieved fusion.

    “For those that haven’t seen my recent posts, it will come as a major surprise that I would even consider believing I had achieved fusion,” he wrote on the Fusor.net forum recently.

    “However, over the past month I have made an enormous amount of progress resulting from fixing major leaks in my system. I now have results that I believe to be worthy.”

    To be clear, these claims have not been peer reviewed as yet – until they’re replicated and the results are published in a peer-review journal, we need to take all of this with a very, very big grain of salt.

    But Oswalt is not the only one who thinks he’s been successful.

    The Open Source Fusor Research Consortium has also verified Oswalt’s results. According to Jason Hull, an administrator on the website, Oswalt has now been added to the hobbyist group’s list of successful fusioneers.

    “Good work. Nice system. You have put some money into this,” Hull wrote, applauding Oswalt’s work.

    He’s not wrong. While Oswalt’s nuclear reactor is considered a “tiny volume fusor”, setting it up in an old playroom in his parents’ house cost something like $10,000 (£7,700).

    What’s even crazier is that Oswalt isn’t the only young teen working on ambitious projects like this.

    If Oswalt’s results are peer-reviewed or verified by a scientific organisation, he will have officially ousted the former record holder, a 14-year-old named Taylor Wilson, as the youngest person to ever achieve nuclear fusion.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 10:59 am on February 22, 2019 Permalink | Reply
    Tags: Fusion technology, LLC, Nuclear power scheme-Twelve-pack of power. C. BICKEL/SCIENCE, NUSCALE POWER, ,   

    From Science Magazine: “Smaller, safer, cheaper: One company aims to reinvent the nuclear reactor and save a warming planet” 

    AAAS
    From Science Magazine

    Feb. 21, 2019
    Adrian Cho

    1
    NuScale researchers want to operate 12 small nuclear reactors from a single control room. They built a mock one in Corvallis, Oregon, to show they can do it.
    NUSCALE POWER, LLC

    To a world facing the existential threat of global warming, nuclear power would appear to be a lifeline. Advocates say nuclear reactors, compact and able to deliver steady, carbon-free power, are ideal replacements for fossil fuels and a way to slash greenhouse gas emissions. However, in most of the world, the nuclear industry is in retreat. The public continues to distrust it, especially after three reactors melted down in a 2011 accident at the Fukushima Daiichi Nuclear Power Plant in Japan. Nations also continue to dither over what to do with radioactive reactor waste. Most important, with new reactors costing $7 billion or more, the nuclear industry struggles to compete with cheaper forms of energy, such as natural gas. So even as global temperatures break one record after another, just one nuclear reactor has turned on in the United States in the past 20 years. Globally, nuclear power supplies just 11% of electrical power, down from a high of 17.6% in 1996.

    Jose Reyes, a nuclear engineer and cofounder of NuScale Power, headquartered in Portland, Oregon, says he and his colleagues can revive nuclear by thinking small. Reyes and NuScale’s 350 employees have designed a small modular reactor (SMR) that would take up 1% of the space of a conventional reactor. Whereas a typical commercial reactor cranks out a gigawatt of power, each NuScale SMR would generate just 60 megawatts. For about $3 billion, NuScale would stack up to 12 SMRs side by side, like beer cans in a six-pack, to form a power plant.

    But size alone isn’t a panacea. “If I just scale down a large reactor, I’ll lose, no doubt,” says Reyes, 63, a soft-spoken native of New York City and son of Honduran and Dominican immigrants. To make their reactors safer, NuScale engineers have simplified them, eliminating pumps, valves, and other moving parts while adding safeguards in a design they say would be virtually impervious to meltdown. To make their reactors cheaper, the engineers plan to fabricate them whole in a factory instead of assembling them at a construction site, cutting costs enough to compete with other forms of energy.

    Spun out of nearby Oregon State University (OSU) here in 2007, NuScale has spent more than $800 million on its design—$288 million from the Department of Energy (DOE) and the rest mainly from NuScale’s backer, the global engineering and construction firm Fluor.

    The design is now working its way through licensing with the Nuclear Regulatory Commission (NRC), and the company has lined up a first customer, a utility association that wants to start construction on a plant in Idaho in 2023.

    NuScale is far from alone. With similar projects rising in China and Russia, the company is riding a global wave of interest in SMRs. “SMRs as a class have a potential to change the economics,” says Robert Rosner, a physicist at the University of Chicago in Illinois who co-wrote a 2011 report on them. In the United States, NuScale is the only company seeking to license and build an SMR. Rosner is optimistic about its prospects. “NuScale has really made the case that they’ll be able to pull it off,” Rosner says.

    For now, NuScale’s reactors exist mostly as computer models. But in an industrial area north of town here, the company has built a full-size mock-up of the upper portion of a reactor. Festooned with pipes, the 8-meter-tall gray cylinder isn’t exactly small. It resembles the conning tower of a submarine, one that has somehow surfaced through the dusty ground. NuScale built it to see if workers could squeeze inside for inspections, says Ben Heald, a NuScale reactor designer. “It’s a great marketing tool.”

    Not everyone thinks NuScale will make the transition from mock-up to reality, however. Dozens of advanced reactor designs have come and gone. And even if NuScale and other startups succeed, the nuclear industry won’t build enough plants quickly enough to matter in the fight against climate change, says Allison Macfarlane, a professor of public policy and geologist at George Washington University in Washington, D.C., who chaired NRC from 2012 through 2014. “Nuclear does not do anything quickly,” she says.

    Nuclear power scheme-Twelve-pack of power. C. BICKEL/SCIENCE

    A nuclear reactor is a glorified boiler. Within its core hang ranks of fuel rods, usually filled with pellets of uranium oxide. The radioactive uranium atoms spontaneously split, releasing energy and neutrons that go on to split more uranium atoms in a chain reaction called fission. Heat from the chain reaction ultimately boils water to drive steam turbines and generate electricity.

    Designs vary, but 85% of the world’s 452 power reactors circulate water through the core to cool it and ferry heat to a steam generator that drives a turbine.

    The water plays a second safety role. Power reactors typically use a fuel with a small amount of the fissile isotope uranium-235. The dilute fuel sustains a chain reaction only if the neutrons are slowed to increase the probability that they’ll split other atoms. The cooling water itself serves to slow, or moderate, the neutrons. If that water is lost in an accident, fission fizzles, preventing a runaway chain reaction like the one that blew up a graphite-moderated reactor in 1986 at the Chernobyl Nuclear Power Plant in Ukraine.

    Even after the chain reaction dies, however, heat from the radioactive decay of nuclei created by fission can melt the core. That happened at Fukushima when a tsunami swamped the emergency generators needed to pump water through the plant’s reactors.

    NuScale’s design would reduce such risks in multiple ways. First, in an accident the small cores would produce far less decay heat. NuScale engineers have also cut out the pumps that drive the cooling water through the core, relying instead on natural convection. That design eliminates moving parts that could fail and cause an accident in the first place, says Eric Young, a NuScale engineer. “If it’s not there, it can’t break,” he says.

    NuScale’s new reactor housings offer further protection. A conventional reactor sits within a reinforced concrete containment vessel up to 40 meters in diameter. Each 3-meter-wide NuScale reactor nestles into its own 4.6-meter-wide steel containment vessel, which by virtue of its much smaller diameter can withstand pressures 15 times greater. The vessels sit submerged in a vast pool of water: NuScale’s ultimate line of defense.

    For example, in an emergency, operators can cool the core by diverting steam from the turbines to heat exchangers in the pool. During normal operations, the space between the reactor and the containment vessel is kept under vacuum, like a thermos, to insulate the core and allow it to heat up. But if the reactor overheats, relief valves would pop open to release steam and water into the vacuum space, where they would transfer heat to the pool. Such passive features ensure that in just about any conceivable accident, the core would remain intact, Reyes says.

    To prove that the reactor will behave as predicted, NuScale engineers have constructed a one-third scale model. A 7-meter tall tangle of pipes, valves, and wires lurks in the corner of a lab at OSU’s department of nuclear engineering. The model aims not to run exactly like the real reactor, Young says, but rather to validate the computer models that NRC will use to evaluate the design’s safety. The model’s core heats water not with nuclear fuel but with 56 electric heaters like those in curling irons, Young says. “It’s like a big percolator,” he says. “We set up a test and watch coffee being made for 3 days.”

    Making a reactor smaller has a downside, says M. V. Ramana, a physicist at the University of British Columbia in Vancouver, Canada. A smaller reactor will extract less energy from every ton of fuel, he argues, driving up operating costs. “There’s a reason reactors became larger,” Ramana says. “Inherently, NuScale is giving up the advantages of economies of scale.”

    But small size pays off in versatility, Reyes says. One little reactor might power a plant to desalinate seawater or supply heat for an industrial process. A customized NuScale plant might support a developing country’s smaller electrical grid. And in the developed world, where intermittent renewable sources are growing rapidly, a full 12-pack of reactors could provide steady power to make up for the fitful output of windmills and solar panels. By varying the number of reactors producing power, a NuScale plant could “load follow” and fill in the gaps, Reyes says.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

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  • richardmitnick 8:14 pm on February 15, 2019 Permalink | Reply
    Tags: "Looking Forward to Fusion", , , Fusion technology, MIT Spectrum, Patrick White,   

    From MIT Spectrum: “Looking Forward to Fusion” 

    MIT Widget

    From MIT Spectrum

    Winter 2019

    1
    Patrick White (photographed in the Plasma Science and Fusion Center) is focused on the policy questions that will arise from the new SPARC technology. Photo: Bryce Vickmark

    Technical policy scholar Patrick White joins the SPARC project to ask: what comes after success?

    Controlled fusion power has been a tantalizing prospect for decades, promising a source of endless carbon-free energy for the world. Unfortunately, persistent technical challenges have kept that achievement on an ever-receding horizon. But recent developments in materials science and superconductivity have changed the landscape. The proposed SPARC experiment of MIT’s Plasma Science and Fusion Center (PSFC), in collaboration with the private, MIT alumni-led company Commonwealth Fusion Systems, is poised to use those breakthroughs to build the first fusion device that generates more energy than it consumes, bringing commercial fusion energy within practical reach in the near future.

    MIT SPARC fusion reactor tokamak

    Patrick White, a PhD candidate in the Department of Nuclear Science and Engineering (NSE), is looking ahead to that long-awaited day. His PhD project, funded by the Samuel W. Ing (1953) Memorial Fellowship in the NSE department and PSFC, anticipates the many questions that will follow a successful SPARC project and the development of fusion power.

    “How do you commercialize this technology that no one’s ever built before?” he asks. “It’s an opportunity to start from scratch.” White is focusing on the regulatory structures and safety analysis tools that will be necessary to bring fusion power plants out of the laboratory and onto the national power grid.

    He first became fascinated with nuclear science and technology while studying mechanical engineering at Carnegie Mellon University. “I think it was the fact that you can take a gram of uranium and release the same energy as several tons worth of coal, or that a single nuclear reactor can power a million homes for 60 years,” he remembers. “That absolutely blew me away.” He saw commercial reactor technology up close during an undergraduate summer internship with Westinghouse, and followed that with two summers in Washington, DC, working with the Defense Nuclear Facilities Safety Board.

    When White came to MIT for graduate work, he joined the MIT Energy Initiative’s major interdisciplinary study, The Future of Nuclear Energy in a Carbon-Constrained World, authoring the regulation and licensing section of the final report (which was subsequently released this past September). He began casting about for a PhD topic around the time the SPARC project was announced.

    The goal of SPARC is to demonstrate net energy from a fusion device in seven years—a key technical milestone that could lead to the construction of a commercially viable power plant scaled up to roughly twice SPARC’s diameter. Because the fusion process produces net energy at extreme temperatures no solid material can withstand, fusion researchers use magnetic fields to keep the hot plasma from coming into contact with the device’s chamber. Currently, the team building SPARC is refining the superconducting magnet technology that will be central to its operation. Already familiar with the regulatory and safety framework that’s been developed over decades of commercial fission reactor operation, White immediately began considering the challenges of regulating an entirely new potential technology that hasn’t yet been invented. One concern in the fusion community, he notes, is that “before we even have a final plant design, the regulatory system could make the ultimate device too expensive or too cumbersome to actually operate. So we’ll be looking at existing nuclear and non-nuclear industries, how they think about safety and regulation, and trying to come up with a pathway that makes the most sense for this new technology.”

    His PhD project proposal on the regulation of commercial fusion plants was selected by the PSFC for funding, and he got down to work in fall 2018 under three advisors: Zach Hartwig PhD ’14, the John C. Hardwick Assistant Professor of Nuclear Science and Engineering; assistant professor Koroush Shirvan SM ’10, PhD ’13; and Dennis Whyte, director of PSFC and the Hitachi America Professor of Engineering.

    White’s career plans beyond the fellowship remain flexible: he notes that whether he ends up working with the licensing of advanced fission reactors or in the new world of commercial fusion power will depend on the technology itself, and how SPARC and other experimental projects evolve. Another possibility is bridging the communications gap between the nuclear industry and a public that’s often apprehensive about nuclear technology: “At the end of the day, if people refuse to have it built in their backyard, you’ve got a great device that can’t actually do any good.”

    For now, White’s fellowship is not only laying the groundwork for his own future, but also perhaps the future of what would be one of the greatest technological advances of humankind. He points out that the stakes are higher than simply developing a new energy technology. “If we’re really concerned about climate change and decarbonizing, we need to have every single tool on the table,” he says. “The more tools, the better.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    MIT Seal

    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

    MIT Campus

     
  • richardmitnick 4:05 pm on January 31, 2019 Permalink | Reply
    Tags: , Fusion technology, , Rochester’s laser lab moves closer to controlled nuclear fusion, , With data science   

    From University of Rochester: “With data science, Rochester’s laser lab moves closer to controlled nuclear fusion” 

    U Rochester bloc

    From University of Rochester

    U Rochester Omega Laser

    Scientists have been working for decades to develop controlled nuclear fusion. Controlled nuclear fusion would improve the ability to evaluate the safety and reliability of the nation’s stockpile of nuclear weapons—in labs in lieu of actual test detonations. And ultimately, it could produce an inexhaustible supply of clean energy.

    But the challenges have been many. Notably, designing optimal fusion experiments requires accurately modeling all of the complex physical processes that occur during an implosion. One of the biggest handicaps has been the lack of accurate predictive models to show in advance how target specifications and laser pulse shapes might be altered to increase fusion energy yields.

    Now researchers at the University of Rochester’s Laboratory for Laser Energetics (LLE), along with colleagues from MIT, have been able to triple fusion yields by bringing data science techniques to previously collected data and computer simulations.

    Approaching a fusion milestone

    Rochester’s Laboratory for Laser Energetics is the largest university-based US Department of Energy program in the nation and is home to the OMEGA laser, the most powerful laser system found at any academic institution.

    U Rochester OMEGA EP Laser System

    The facility has taken the lead in the laser direct-drive approach to fusion energy by blasting spherical deuterium-tritium fuel pellets with 60 laser beams, converging directly on the pellet surface from all directions at once. This causes the pellet to heat and implode, forming a plasma. If sufficiently high temperatures and pressures could be confined at the center of the implosion, a thermonuclear burn wave would propagate radially through the entire fuel mass, producing fusion energy yields many times greater than the energy input.

    The latest increase in yields, reported in Nature, bring scientists closer to an important milestone in their quest to achieve controlled thermonuclear fusion – getting the plasma to self-ignite, enabling an output of fusion energy that equals the laser energy coming in.

    “That would be a major achievement but it will require energies much larger than the OMEGA laser such as at the NIF at Lawrence Livermore National Laboratory,” says Michael Campbell, LLE’s director.


    National Ignition Facility at LLNL

    Bridging the gap between experiments and simulations

    To create a predictive model, Varchas Gopalaswamy and Dhrumir Patel, PhD students in mechanical engineering, and their supervisor Riccardo Betti, chief scientist and Robert L . McCrory Professor at LLE, applied data science techniques to results from about 100 previous fusion experiments at OMEGA.

    “We were inspired from advances in machine learning and data science over the last decade,” Gopalaswamy says. Adds Betti: “This approach bridges the gap between experiments and simulations to improve the predictive capability of the computer programs used in the design of experiments.”

    The statistical analysis guided LLE scientists in altering the target specifications and temporal shape of the laser pulse used in the fusion experiments. The task required a concerted effort by LLE experimental physicists who set up the experiments, and theorists who develop the simulation codes. James Knauer, LLE senior scientist, led the experimental campaign.

    “These experiments required exquisite control of the laser pulse shape,” Knauer says. Patel applied the statistical technique to design the laser pulse shape leading to the best performing implosion.

    “This was a very, very unusual pulse shape for us,” Campbell says. And yet, within three or four subsequent experiments, according to Campbell, an experiment was designed that produced 160 trillion fusion reactions, tripling the previous record at OMEGA.

    “Only thanks to the dedication and expertise of the facility crew, target fabrication, cryogenic layering and system scientists, were we able to control the target quality and the laser pulse to the precision required for these experiments,” Betti says.

    Extrapolating to the National Ignition Facility

    When extrapolated to match the 70-times more powerful laser-energies used at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, these implosions would be expected to produce about 1,000 times more fusion reactions. Under the right conditions, a modest improvement in target compression on OMEGA could be enough to approach breakeven conditions at NIF energy levels, with the fusion energy output equaling the laser energy input. “Extrapolating the results from OMEGA to NIF is a tricky business. It is not just a size and energy issue. There are also qualitative differences that need to be assessed” Betti said. For this purpose, a parallel effort by LLE scientists in collaboration with colleagues at Lawrence Livermore and the Naval Research Laboratory (NRL) is underway at the NIF to verify that OMEGA results can be extrapolated to NIF energies.

    The NIF is configured for an indirect drive approach to fusion experiments, in which the fuel capsule is enclosed within a metal cylindrical can called a hohlraum. Laser beams enter from the can ends and heat the hohlraum, which in turns produces x-rays that cause the fuel to implode. Unlike OMEGA, NIF beams are not positioned symmetrically, but are instead concentrated along the axis of the hohlraum. The indirect drive scheme has also made major progress in recent experiments at the NIF. “They are getting close to achieve burning-plasma conditions,” Campbell says.

    “The next couple of years we will do experiments on OMEGA using the same asymmetric laser configuration of the NIF, and see what the penalty is.”

    The paper lists a total of 50 LLE scientists and students as coauthors, along with four collaborators from MIT. The target components were made by General Atomics to meet very strict tolerances.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Rochester Campus

    The University of Rochesteris one of the country’s top-tier research universities. Our 158 buildings house more than 200 academic majors, more than 2,000 faculty and instructional staff, and some 10,500 students—approximately half of whom are women.

    Learning at the University of Rochester is also on a very personal scale. Rochester remains one of the smallest and most collegiate among top research universities, with smaller classes, a low 10:1 student to teacher ratio, and increased interactions with faculty.

     
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