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  • richardmitnick 2:41 pm on June 25, 2020 Permalink | Reply
    Tags: "Scientists develop new tool to design better fusion devices", , PPPL,   

    From PPPL: “Scientists develop new tool to design better fusion devices” 


    From PPPL

    June 24, 2020
    Raphael Rosen

    One way that scientists seek to bring to Earth the fusion process that powers the sun and stars is trapping hot, charged plasma gas within a twisting magnetic coil device shaped like a breakfast cruller. But the device, called a stellarator, must be precisely engineered to prevent heat from escaping the plasma core where it stokes the fusion reactions.

    Wendelstgein 7-X stellarator, built in Greifswald, Germany

    Now, researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have demonstrated that an advanced computer code could help design stellarators that confine the essential heat more effectively.

    The code, called XGC-S, opens new doors in stellarator research. “The main result of our research is that we can use the code to simulate both the early, or linear, and turbulent plasma behavior in stellarators,” said PPPL physicist Michael Cole, lead author of the paper reporting the results in Physics of Plasmas. “This means that we can start to determine which stellarator shape contains heat best and most efficiently maintains conditions for fusion.”

    Fusion combines light elements in the form of plasma — the hot, charged state of matter composed of free electrons and atomic nuclei — and generates massive amounts of energy in the sun and stars. Scientists aim to replicate fusion in devices on Earth for a virtually inexhaustible supply of safe and clean power to generate electricity.

    The PPPL scientists simulated the behavior of plasma inside fusion machines that look like a donut but with pinches and deformations that make the device more efficient, a kind of shape known as quasi-axisymmetric . The researchers used an updated version of XGC, a state-of-the-art code developed at PPPL for modeling turbulence in doughnut-shaped fusion facilities called tokamaks, which have a simpler geometry. The modifications by Cole and his colleagues allowed the new XGC-S code to also model plasmas in the geometrically more complicated stellarators.

    The simulations showed that a type of disturbance limited to a small area can become complex and expand to fill a larger space within the plasma. The results showed that XGC-S could simulate this type of stellarator plasma more accurately than what was previously possible.

    “I think this is the beginning of a really important development in the study of turbulence in stellarators,” said David Gates, head of the Department of Advanced Projects at PPPL. “It opens up a big window for getting new results.”

    The findings demonstrate the successful modification of the XGC code to simulate turbulence in stellarators. The code can calculate the turbulence in stellarators all the way from the plasma core to the edge, providing a more complete picture of the plasma’s behavior.

    “Turbulence is one of the primary mechanisms causing heat to leak out of fusion plasmas,” Cole said. “Because stellarators can be built in a greater variety of shapes than tokamaks, we might be able to find shapes that control turbulence better than tokamaks do. Searching for them by building lots of big experiments is too expensive, so we need big simulations to search for them virtually.”

    The researchers plan to modify XGC-S further to produce an even clearer view of how turbulence causes heat leakage. The more complete a picture, the closer scientists will be to simulating stellarator experiments in the virtual realm. “Once you have an accurate code and a powerful computer, changing the stellarator design you are simulating is easy,” Cole said.

    Researchers performed the simulations using resources at the National Energy Research Scientific Computing Center (NERSC), a DOE User Facility. Support for this research came from the DOE Office of Science (Fusion Energy Sciences).

    See the full article here .


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    Please help promote STEM in your local schools.

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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.http://www.energy.gov.

    Princeton University campus

     
  • richardmitnick 10:33 am on May 27, 2020 Permalink | Reply
    Tags: "Return of the Blob: Scientists find surprising link to troublesome turbulence at the edge of fusion plasmas", Blobs can wreak havoc in plasma required for fusion reactions., , , PPPL   

    From PPPL: “Return of the Blob: Scientists find surprising link to troublesome turbulence at the edge of fusion plasmas” 


    From PPPL

    May 26, 2020
    John Greenwald

    1
    Image showing spiraling magnetic field fluctuations at the edge of the NSTX tokamak. (Photo courtesy of Physics of Plasmas. Composition by Elle Starkman/Office of Communications.)

    PPPL NSTX -U at Princeton Plasma Physics Lab, Princeton, NJ,USA

    Blobs can wreak havoc in plasma required for fusion reactions. This bubble-like turbulence swells up at the edge of fusion plasmas and drains heat from the edge, limiting the efficiency of fusion reactions in doughnut-shaped fusion facilities called “tokamaks.” Researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have now discovered a surprising correlation of the blobs with fluctuations of the magnetic field that confines the plasma fueling fusion reactions in the device core.

    New aspect of understanding

    Further investigation of this correlation and its role in the loss of heat from magnetic fusion reactors will help to produce on Earth the fusion energy that powers the sun and stars. “These results add a new aspect to our understanding of the plasma edge heat loss in a tokamak,” said physicist Stewart Zweben, lead author of a paper (link is external) in Physics of Plasmas that editors have selected as a featured article. “This work also contributes to our understanding of the physics of blobs, which can help to predict the performance of tokamak fusion reactors.”

    Fusion reactions combine light elements in the form of plasma — the hot, charged state of matter composed of free electrons and atomic nuclei that makes up 99 percent of the visible universe — to produce massive amounts of energy. Scientists are seeking to create and control fusion on Earth as a source of safe, clean and virtually limitless power to generate electricity.

    PPPL researchers discovered the surprising link last year when re-analyzing experiments made in 2010 on PPPL’s National Spherical Torus Experiment (NSTX) — the forerunner of today’s National Spherical Torus Experiment-Upgrade (NSTX-U). The blobs and fluctuations in the magnetic field, called “magnetohydrodynamic (MHD)” activity, develop in all tokamaks and have traditionally been seen as independent of each other.

    Surprise clue

    The first clue to the correlation was the striking regularity of the trajectory of large blobs, which travel at roughly the speed of a rifle bullet, in experiments analyzed in 2015 and 2016. Such blobs normally move randomly in what is called the “scrape-off layer” at the edge of tokamak plasma, but in some cases all large blobstraveled at nearly the same angle and speed. Moreover, the time between the appearance of each large blob at the edge of the plasma was nearly always the same, virtually coinciding with the frequency of dominant MHD activity in the plasma edge.

    Researchers then tracked the diagnostic signals of the blobs and the MHD activity in relation to each other to measure what is called the “cross-correlation coefficient,” which they used to evaluate a set of the 2010 NSTX experiments. Roughly 10 percent of those experiments were found to show a significant correlation between the two variables.

    The scientists then analyzed several possible causes of the correlation, but could find no single compelling explanation. To understand and control this phenomenon, Zweben said, further data analysis and modeling will have to be done — perhaps by readers of the Physics of Plasmas paper.

    Support for this work comes from the DOE Office of Science, with portions of the research performed under the auspices of Lawrence Livermore National Laboratory.

    See the full article here .


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    Please help promote STEM in your local schools.

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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.http://www.energy.gov.

    Princeton University campus

     
  • richardmitnick 2:26 pm on April 16, 2020 Permalink | Reply
    Tags: "Applying mathematics to accelerate predictions for capturing fusion energy", PPPL   

    From PPPL: “Applying mathematics to accelerate predictions for capturing fusion energy” 


    From PPPL

    April 14, 2020
    John Greenwald

    1
    Physicist Ben Sturdevant with figures from paper. (Photo and composite by Elle Starkman/PPPL Office of Communications.)

    A key issue for scientists seeking to bring the fusion that powers the sun and stars to Earth is forecasting the performance of the volatile plasma that fuels fusion reactions. Making such predictions calls for considerable costly time on the world’s fastest supercomputers. Now researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have borrowed a technique from applied mathematics to accelerate the process.

    The technique combines the millisecond behavior of fusion plasmas into longer-term forecasts. By using it, “we were able to demonstrate that accurate predictions of quantities such as plasma temperature profiles and heat fluxes could be achieved at a much reduced computational cost,” said Ben Sturdevant, an applied mathematician at PPPL and lead author of a Physics of Plasmas paper that reported the results.

    Fusion combines light elements in the form of plasma — the hot, charged state of matter composed of free electrons and atomic nuclei — that generates massive amounts of energy. Scientists are working around the world to create and control fusion on Earth for a virtually inexhaustible supply of safe and clean power to generate electricity.

    Speeding simulations

    Sturdevant applied the mathematical technique to the high-performance XGCa plasma code developed by a team led by physicist C.S. Chang at PPPL. The application greatly speeded up simulations of the evolving temperature profile of ions orbiting around magnetic field lines modeled with gyrokinetics — a widely used model that provides a detailed microscopic description of the behavior of plasma in strong magnetic fields. Also accelerated was modeling the collisions between orbiting particles that cause heat to leak from the plasma and reduce its performance.

    The application was the first successful use of the technique, called “equation-free projective integration,” to model the evolution of the ion temperature as colliding particles escape from magnetic confinement. Equation free modeling aims to extract long-term macroscopic information from short-term microscopic simulations. The key was improving a critical aspect of the technique called a “lifting operator” to map the large-scale, or macroscopic, states of plasma behavior onto small-scale, or microscopic, ones.

    The modification brought the detailed profile of the ion temperature into sharp relief. “Rather than directly simulating the evolution over a long time-scale, this method uses a number of millisecond simulations to make predictions over a longer time-scale,” Sturdevant said. “The improved process reduced the computing time by a factor of four.”

    The results, based on tokamak simulations, are general and could be adapted for other magnetic fusion devices including stellarators and even for other scientific applications. “This is an important step in being able to confidently predict performance in fusion energy devices from first-principles-based physics,” Sturdevant said.

    Expanding the technique

    He next plans to consider the effect of expanding the technique to include the evolution of turbulence on the speed of the process. “Some of these initial results are promising and exciting,” Sturdevant said. “We’re very interested to see how it will work with the inclusion of turbulence.”

    Coauthors of the paper include Chang, PPPL physicist Robert Hager and physicist Scott Parker of the University of Colorado. Chang and Parker were advisors, Sturdevant said, while Hager provided help with the XGCa code and the computational analysis.

    Support for this work comes from the Exascale Computing Project, a collaborative effort of the DOE Office of Science and the National Nuclear Security Administration, and Scientific Discovery through Advanced Computing (SciDAC). Computer simulations were performed at the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility.

    2

    See the full article here .


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

    Stem Education Coalition


    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.http://www.energy.gov.

    Princeton University campus

     
  • richardmitnick 1:06 pm on February 13, 2020 Permalink | Reply
    Tags: "Investigating the trigger for a sudden explosive process that occurs throughout the universe", Lundquist number, PPPL   

    From PPPL and Princeton University : “Investigating the trigger for a sudden explosive process that occurs throughout the universe” 

    Princeton University
    From Princeton University

    and

    From PPPL

    February 12, 2020
    John Greenwald

    1
    Physicist Yi-Min Huang. (Photo by Elle Starkman/Office of Communications)

    A long-standing puzzle in space science is what triggers fast magnetic reconnection, an explosive process that unfolds throughout the universe more rapidly than theory says it should.

    NASA Magnetic reconnection, Credit: M. Aschwanden et al. (LMSAL), TRACE, NASA

    Solving the puzzle could enable scientists to better understand and anticipate the process, which ignites solar flares and magnetic space storms that can disrupt cell phone service and black out power grids on Earth.

    Magnetic reconnection separates and violently reconnects the magnetic fields in plasma, the state of matter composed of free electrons and atomic nuclei that make up 99 percent of the visible universe. Researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University have recently produced a formula for tracking the development of “plasmoid-instability-mediated disruptions,” which trigger the transition from slow to fast reconnection.

    The research traces the dependence of the instability on conditions ranging from the electrical conductivity of the plasma — measured by what is called the Lundquist number — to the natural noise of the system. “You give me the Lundquist number and system noise and I can fit it into the formula that will spit out the answer,” said physicist Yi-Min Huang, a Princeton University member of the PPPL Theory Department and lead author of a paper describing the process in Physics of Plasmas.

    Tracking the evolution of “plasmoids”

    The calculation tracks the evolution of plasmoids, bubbles that form in current-carrying sheets of plasma. When the bubbles are large enough, they trigger disruptions that cause fast reconnection. “We are interested in finding out when the plasmoids will disrupt the current sheet and the number of plasmoids when disruptions happen,” Huang said.

    The formula for relating the factors that lead to disruptions is based on a complex “phenomenological” model — one deduced from a combination of physical reasoning and mathematical derivation. “As a general rule,” Huang said, “a phenomenological model must be tested through numerical simulations” against first-principle, or standard, physics models.

    The versatile new formula tracks the dependence of disruptions on a broad range of high Lundquist numbers. Derived results can be compared with simulations of laboratory experiments and used to describe the development of plasmoid instabilities in natural systems.
    Previously, the dependence could only be obtained by solving the equations of the complex model, Huang said.

    Co-authors of the Physics of Plasmas paper were Luca Comisso of Columbia University and Amitava Bhattacharjee, head of PPPL’s Theory Department. Support for the research comes from the National Science Foundation, the DOE Office of Science and the National Aeronautics and Space Administration.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    About Princeton: Overview

    Princeton University is a vibrant community of scholarship and learning that stands in the nation’s service and in the service of all nations. Chartered in 1746, Princeton is the fourth-oldest college in the United States. Princeton is an independent, coeducational, nondenominational institution that provides undergraduate and graduate instruction in the humanities, social sciences, natural sciences and engineering.

    As a world-renowned research university, Princeton seeks to achieve the highest levels of distinction in the discovery and transmission of knowledge and understanding. At the same time, Princeton is distinctive among research universities in its commitment to undergraduate teaching.

    Today, more than 1,100 faculty members instruct approximately 5,200 undergraduate students and 2,600 graduate students. The University’s generous financial aid program ensures that talented students from all economic backgrounds can afford a Princeton education.

    Princeton Shield


    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.http://www.energy.gov.

    Princeton University campus

     
  • richardmitnick 3:37 pm on November 13, 2019 Permalink | Reply
    Tags: A goal of instilling entrepreneurship, , , Funding for research liaisons, , PPPL, PPPL wins DOE funding for entrepreneurship"   

    From PPPL: “PPPL wins DOE funding for entrepreneurship” 

    From PPPL

    November 13, 2019
    Jeanne Jackson DeVoe

    1
    Craig Arnold, a professor of Aerospace Engineering at Princeton University, and founder of TAG Optics Inc., discusses his experiences starting a business at the Jan. 23 Entrepreneurship Lunch and Learn in the MBG Auditorium. (Photo by Elle Starkman/PPPL Office of Communications)

    The U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) will expand an entrepreneurship “lunch and learn” program pioneered at PPPL last year and appoint mentors to help and encourage potential entrepreneurs in the Laboratory through two U.S. Department of Energy (DOE) projects totaling $70,000 awarded to PPPL’s Technology Transfer Office.

    PPPL will participate in three and receive funding for two of 12 projects through DOE’s Practices to Accelerate the Commercialization of Technologies (PACT) program developed by DOE’s Office of Technology Transition (OTT) to help promote the transition of inventions developed at the 17 national laboratories and plants to the marketplace.

    “I’m thrilled that PPPL received these awards,” said Laurie Bagley, head of Technology Transfer. “We are delighted to have the funding to provide support and training to our entrepreneurs, as well as to provide mentorship and training in collaboration with other laboratories.

    A goal of instilling entrepreneurship

    Steve Cowley, laboratory director, said he is glad to see funding for programs that encourage PPPL inventors. He noted that the DOE set a goal of instilling a culture of entrepreneurship as a “notable” requirement for all national laboratory directors in fiscal years 2019 and 2020. “One of PPPL’s major goals is to develop useful new technologies of all kinds,” Cowley said. “Laurie has done a wonderful job in developing programs to encourage entrepreneurship and these awards are a reflection of that. I hope everyone on our staff will take advantage of these programs and learn how to bring out their inner inventors.”

    PPPL received $40,000 from the DOE’s Office of Technology Transitions to continue and expand the Entrepreneurship Lunch and Learn program begun last year by Bagley, to offer information and support to current and future entrepreneurs at the Laboratory. The additional funds will allow PPPL to bring in a wider variety of experts on a range of topics affecting entrepreneurs, Bagley said. Topics could include how to identify ideal customers, developing marketing leads and plans, intellectual property’s role in a start-up, and entrepreneur success stories. The talks could also help improve the skill set of inventors presenting their technologies at events such as the Innovation Discovery Events, technology showcases or Energy I-Corps programs, Bagley said.

    This award is aimed at encouraging entrepreneurship throughout PPPL’s staff, not just physicists and engineers. “The goal is to get people here thinking more entrepreneurially, so if they are working on a technology that can be patented or have an idea to start a business, they’ll have a deeper understanding to make those decisions,” Bagley said.

    PPPL’s Office of Technology Transfer offered four such talks last year to audience members and ranged from advice from a Princeton University entrepreneur on the challenges of starting a business to services available to entrepreneurs through Princeton University and the DOE’s Office of Technology Transition’s Program.

    Funding for research liaisons

    The Laboratory will also participate in a $30,000 project through a new pilot initiative, the DOE Technology Transfer Research Liaison Program. The program was championed by Oak Ridge National Laboratory (ORNL) as a collaborative effort with 11 national laboratories, including PPPL. The idea is to strengthen the relationship between the lab’s tech transfer office and its researchers and engineers to identify inventors and encourage and advise them about how to develop technologies, some of which can eventually be brought to market. PPPL will select three liaisons, who will receive training along with liaisons at other laboratories. The liaisons will then serve as champions and mentors by offering help and encouragement on questions about invention disclosures, patents, and other technology transfer issues.

    In addition to the awards, PPPL was named as one of 11 partners in another new DOE program, Diversity and Inclusion in InVentorship and EntrepReneurship Strategies and Engagement (DIVERSE), which is aimed at encouraging a more diverse pool of inventors and entrepreneurs.

    See the full article here .


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

    Stem Education Coalition


    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.http://www.energy.gov.

    Princeton University campus

     
  • richardmitnick 1:06 pm on September 20, 2019 Permalink | Reply
    Tags: "How to predict crucial plasma pressure in future fusion facilities", Accurate predictions of the pressure of the plasma, , , , PPPL   

    From PPPL- “Today’s forecast: How to predict crucial plasma pressure in future fusion facilities” 

    From PPPL

    September 20, 2019
    John Greenwald

    1
    Physicist Michael Churchill. (Photo by Elle Starkman/Office of Communications)

    A key requirement for future facilities that aim to capture and control on Earth the fusion energy that drives the sun and stars is accurate predictions of the pressure of the plasma — the hot, charged gas that fuels fusion reactions inside doughnut-shaped tokamaks that house the reactions. Central to these predictions is forecasting the pressure that the scrape-off layer, the thin strip of gas at the edge of the plasma, exerts on the divertor — the device that exhausts waste heat from fusion reactions.

    Researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have developed new insights into the physics governing the balance of pressure in the scrape-off layer. This balance must ensure that the pressure of the plasma throughout the tokamak is high enough to produce a largely self-heating fusion reaction. The balance must also limit the potentially damaging impact of heat and plasma particles that strike the divertor and other plasma-facing components of the tokamak.

    “Previous simple assumptions about the balance of pressure in the scrape-off layer are incomplete,” said PPPL physicist Michael Churchill, lead author of a Nuclear Fusion paper that describes the new findings. “The codes that simulate the scrape-off layer have often thrown away important aspects of the physics, and the field is starting to recognize this.”

    Fusion, the power that 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 massive amounts of energy. Scientists are seeking to replicate fusion on Earth for a virtually inexhaustible supply of power to generate electricity.

    Key factors

    Churchill and PPPL colleagues determined the key factors behind the pressure balance by running the state-of-the-art XGCa computer code on the Cori and Edison supercomputers at the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility.

    NERSC at LBNL

    NERSC Cray Cori II supercomputer, named after Gerty Cori, the first American woman to win a Nobel Prize in science

    NERSC Hopper Cray XE6 supercomputer, named after Grace Hopper, One of the first programmers of the Harvard Mark I computer

    NERSC Cray XC30 Edison supercomputer

    NERSC GPFS for Life Sciences


    The Genepool system is a cluster dedicated to the DOE Joint Genome Institute’s computing needs. Denovo is a smaller test system for Genepool that is primarily used by NERSC staff to test new system configurations and software.

    NERSC PDSF computer cluster in 2003.

    PDSF is a networked distributed computing cluster designed primarily to meet the detector simulation and data analysis requirements of physics, astrophysics and nuclear science collaborations.

    Future:

    Cray Shasta Perlmutter SC18 AMD Epyc Nvidia pre-exascale supeercomputer

    NERSC is a DOE Office of Science User Facility.

    The code treats plasma at a detailed kinetic — or particle motion— level rather than as a fluid.

    Among key features found was the impact of the bulk drift of ions, an impact that previous codes have largely ignored. Such drifts “can play an integral role” the authors wrote, and “are very important to take into account.”

    Also seen to be important in the momentum or pressure balance were the kinetic particle effects due to ions having different temperatures depending on their direction. Since the temperature of ions is hard to measure in the scrape-off layer, the paper says, “increased diagnostic efforts should be made to accurately measure the ion temperature and flows and thus enable a better understanding of the role of ions in the SOL.”

    The new findings could improve understanding of the scrape-off layer pressure at the divertor, Churchill said, and could lead to accurate forecasts for the international ITER experiment under construction in France and other next-generation tokamaks.

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

    Support for this work comes from the DOE Office of Science under the SciDAC Center for High Fidelity Boundary Plasma Simulation (HBPS). The research used resources of the National Energy Research Scientific Computing Center (NERSC). Coauthors of the paper were PPPL physicists C.S Chang, Seung-Ho Ku, Robert Hager, Rajesh Maingi, Daren Stotler and Hong Qin.

    See the full article here .


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

    Stem Education Coalition


    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.http://www.energy.gov.

    Princeton University campus

     
  • richardmitnick 8:12 pm on September 5, 2019 Permalink | Reply
    Tags: "New national facility will explore low-temperature plasma a dynamic source of innovation for modern technologies", Also to be explored is the interface between plasma and solid-state physics., Low-temperature plasma contrasts with the superhot plasma that PPPL investigates that fuels the fusion energy that powers the sun and stars., PPPL, Scientists at PPPL and Princeton will provide guidance to collaborators who come to the facility from companies universities and laboratories throughout the country., The new facility will launch this October with U.S. Department of Energy (DOE) funding of $1.2 million a year for five years., The Princeton Plasma Physics Laboratory (PPPL) has teamed with Princeton University to become home to a collaborative facility open to researchers from across the country ., The total venture supported by the DOE’s Office of Science will be part of the Plasma Science and Technology Department at PPPL.   

    From PPPL: “New national facility will explore low-temperature plasma, a dynamic source of innovation for modern technologies” 

    From PPPL

    September 5, 2019
    John Greenwald

    1
    Princeton collaborative research team from left: Mikhail Shneider; Igor Kaganovich; Yevgeny Raitses; Sophia Gershman; Nirbhav Chopra, Princeton plasma physics graduate student who will use the new facility; Shurik Yatom; Arthur Dogariu. (Photo by Elle Starkman/Office of Communications)

    Low-temperature plasma, a rapidly expanding source of innovation in fields ranging from electronics to health care to space exploration, is a highly complex state of matter. So complex that the Princeton Plasma Physics Laboratory (PPPL) has teamed with Princeton University to become home to a collaborative facility open to researchers from across the country to advance the understanding and control of this dynamic physical state.

    Extensive resources

    The new facility, to launch this October with U.S. Department of Energy (DOE) funding of $1.2 million a year for five years, opens the extensive diagnostic and computational resources at PPPL and Princeton to the academic, scientific and industrial communities. More than 40 researchers are estimated to be interested in topics that the facility will explore, said PPPL physicist Yevgeny Raitses, principal investigator of the new unit, the Princeton Collaborative Research Facility on Low Temperature Plasma.

    Raitses heads the PPPL Laboratory for Plasma Nanosynthesis, which pioneers research on low-temperature plasma to improve the production of nanoparticles — substances millions of times thinner than a human hair found in everything from swimwear to pharmaceuticals. All state-of-the-art instruments housed in the plasma nanosynthesis laboratory will become available to collaborators in the new facility.

    Raitses and physicist Igor Kaganovich, deputy head of the PPPL Theory Department, have long extended the outreach of low-temperature plasma research. Over the past 10 years they have collaborated with companies on topics ranging from the fabrication of microchips to the production of medical treatments to the development of a power switch to modernize the electric grid.

    “World-class program”

    Such companies could now make use of the new facility. “I am delighted with this award,” PPPL Director Steve Cowley said of the new collaborative unit. “Through the leadership of Yevgeny and Igor and collaborations with Princeton University we have developed a world-class program in low temperature plasma science — this will take us to another level.”

    Low-temperature plasma contrasts with the superhot plasma that PPPL investigates that fuels the fusion energy that powers the sun and stars. Fusion plasmas consist chiefly of free-floating electrons and atomic nuclei, or ions, while low-temperature plasmas, which are up to 10,000 times cooler, include a large complement of neutral and partially ionized atoms mixed in with these particles.

    The mixture interacts with solids and liquids to produce applications in a wide range of fields. Among the key topics the facility will explore are interactions with liquids that can affect chemical processes and improve the production of environmental and health care systems, to cite two examples.

    New explorations

    Also to be explored is the interface between plasma and solid-state physics. The process could lead to low-cost and high-volume production of photovoltaic cells for turning sunlight into electricity, among other developments affecting solid-state matter.

    Hosting such research comes naturally to PPPL, the only national laboratory dedicated to the study of fusion energy and plasma science. “It’s important for the nation’s plasma physics lab to make a major contribution to understanding the physics of low-temperature plasmas,” said Jon Menard, deputy director for research at PPPL. “This facility will open all the tools in the laboratory’s low-temperature area for wider use.”

    Scientists at PPPL and Princeton will provide guidance to collaborators who come to the facility from companies, universities and laboratories throughout the country. Among physicists joining Raitses and Kaganovitch on the PPPL team will be Sophia Gershman, an expert in the interaction of plasma and liquids, and Shurik Yatom, who has developed methods for characterizing the synthesis of nanoparticles in plasma in situ, or while the process is taking place. Additional PPPL physicists will conduct research and give guidance to researchers using of the facility.

    Princeton laboratories and centers

    Heading the Princeton University team will be physicists Mikhail Shneider, an expert in plasma physics, fluid dynamics and non-linear optics, who will serve as co-principal investigator. Arthur Dogariu, who pioneered several advanced optical diagnostic techniques, will lead the collaborative center’s experimental efforts at Princeton. University laboratories and centers, including the Princeton Institute for the Science and Technology of Materials (PRISM), will provide access to collaborators, with faculty members and graduate students serving as users and partners in the new facility.

    The total venture, supported by the DOE’s Office of Science, will be part of the Plasma Science and Technology Department at PPPL that physicist Philip Efthimion heads. “We’ll be offering our diagnostic and computer modeling tools to the research community and the private sector,” Efthimion said. “This will provide new opportunities to collaborate between the community and the private sector and to expand our research on low-temperature plasmas.”

    See the full article here .


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

    Stem Education Coalition


    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.http://www.energy.gov.

    Princeton University campus

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

    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

    1
    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 .


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

    Stem Education Coalition


    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 4:28 pm on February 7, 2019 Permalink | Reply
    Tags: , , , , MRI [magnetorotational instability], PPPL   

    From PPPL: “Novel experiment validates a widely speculated and important mechanism during the formation of stars and planets” 


    From PPPL

    February 5, 2019
    John Greenwald

    1
    Water-filled version of MRI [magnetorotational instability] experiment showing transparent outer cylinder and blackened inner cylinder. Red lasers enter at bottom to measure the local speed of the water. (Photo courtesy of Eric Edlund and Elle Starkman)

    How have stars and planets developed from the clouds of dust and gas that once filled the cosmos? A novel experiment at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) has demonstrated the validity of a widespread theory known as “magnetorotational instability,” or MRI, that seeks to explain the formation of heavenly bodies.

    The theory holds that MRI allows accretion disks, clouds of dust, gas, and plasma that swirl around growing stars and planets as well as black holes, to collapse into them. According to the theory, this collapse happens because turbulent swirling plasma, technically known as “Keplerian flows,” gradually grows unstable within a disk. The instability causes angular momentum — the process that keeps orbiting planets from being drawn into the sun — to decrease in inner sections of the disk, which then fall into celestial bodies.

    Unlike orbiting planets, the matter in dense and crowded accretion disks may experience forces such as friction that cause the disks to lose angular momentum and be drawn into the objects they swirl around. However, such forces cannot fully explain how quickly matter must fall into larger objects for planets and stars to form on a reasonable timescale.

    MRI experiment

    At PPPL, physicists have simulated the hypothesized broader process in the laboratory’s MRI experiment. The unique device consists of two concentric cylinders that rotate at different speeds. In this experiment, researchers filled the cylinders with water and attached a water-filled plastic ball tethered by a spring to a post in the center of the device; the stretching and bending spring mimicked the magnetic forces in the plasma in accretion disks. Researchers then rotated the cylinders and videoed the behavior of the ball as seen from the top down.

    The findings, reported in Communications Physics, compared the motions of the spring-tethered ball when rotating at different speeds. “With no stretching, nothing happens to the angular momentum,” said Hantao Ji, a professor of astrophysical sciences at Princeton University and principal researcher on the MRI and a coauthor of the paper. “Nothing also happens if the spring is too strong.”

    However, direct measurement of the results found that when the spring-tethering was weak — analogous to the condition of the magnetic fields in accretion disks —behavior of the angular momentum of the ball was consistent with MRI predictions of developments in a real accretion disk. The findings showed that the weakly tethered rotating ball gained angular momentum and shifted outward during the experiment. Since the angular momentum of a rotating body must be conserved, any gains in momentum must be matched by a loss of momentum in the inner section, allowing gravity to draw the disk into the object it has been orbiting.

    Contributing to research for this paper was lead author Derek Hung, a former Princeton graduate student, together with physicists Erik Gilson and Kyle Caspary of PPPL and astrophysicist Eric Blackman of the Department of Physics and Astronomy and the Laboratory for Laser Energetics at the University of Rochester, who brought up the idea. Support for this work comes from NASA, the National Science Foundation, the DOE Office of Science, the Simons Foundation, the Institute for Advanced Study, and the Kavli Institute for Theoretical Physics.

    See the full article here .


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

    Stem Education Coalition


    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 2:09 pm on December 7, 2018 Permalink | Reply
    Tags: , Magnetospheric Multiscale Satellite (MMS) mission launched in 2015, , PPPL, Princeton Magnetic Reconnection Experiment (MRX) at PPPL   

    From PPPL: “Experiments at PPPL show remarkable agreement with satellite sightings” 


    From PPPL

    December 7, 2018
    John Greenwald

    1
    Members of the MRX team with the device in the background. From left, Masaaki Yamada, Jongsoo Yoo, Jonathan Jara-Almonte, Will Fox, and Hantao Ji.
    (Photo by Elle Starkman/PPPL Office of Communications)

    1
    Illustration of the MMS spacecraft in orbit in Earth’s magnetic field. NASA

    As on Earth, so in space. A four-satellite mission that is studying magnetic reconnection — the breaking apart and explosive reconnection of the magnetic field lines in plasma that occurs throughout the universe — has found key aspects of the process in space to be strikingly similar to those found in experiments at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL). The similarities show how the studies complement each other: The laboratory captures important global features of reconnection and the spacecraft documents local key properties as they occur.

    NASA Magnetic reconnection, Credit: M. Aschwanden et al. (LMSAL), TRACE, NASA

    The observations made by the Magnetospheric Multiscale Satellite (MMS) mission, which NASA launched in 2015 to study reconnection in the magnetic field that surrounds the Earth, correspond quite well with past and present laboratory findings of the Magnetic Reconnection Experiment (MRX) at PPPL. Previous MRX research uncovered the process by which rapid reconnection occurs and identified the amount of magnetic energy that is converted to particle energy during the process, which gives rise to northern lights, solar flares and geomagnetic storms that can disrupt cell phone service, black out power grids and damage orbiting satellites.

    Guidelines for MMS measurements

    The previous MRX findings served as guidelines for measurements taken by the MMS mission, which seeks to understand the region in which the reconnection of field lines in plasma — the state of matter composed of free electrons and atomic nuclei, or ions — takes place. The latest PPPL experiments extend the findings to new areas of agreement. “Despite huge differences in the size of the reconnection layers in the MRX and in space, remarkably similar characteristics are observed in both,” said Masaaki Yamada, principal investigator on the MRX, and lead author of the recent paper reporting the results in the December 6 edition of Nature Communications .

    The past laboratory research examined “symmetric” reconnection, in which the density of the plasmas on each side of the reconnection regions are roughly the same. The new paper looks at reconnection in the magnetopause — the outer region of the magnetosphere — and in the MRX that is “asymmetric,” meaning that the plasma on one side of the region is at least 10 times denser than on the other. The MMS mission has focused its initial research on the asymmetric aspect of reconnection, since the plasma in the solar wind — the charged particles flowing from the sun — is vastly denser than the plasma in the magnetosphere.

    In the new paper, researchers examine what is called the “two-fluid” physics of reconnection that describes each behavior of ions and electrons differently during the process. Such physics dominates magnetic reconnection in both MRX and magnetospheric plasma systems, allowing for an unprecedented level of cross-examination between laboratory measurements and space observations.

    Key findings

    Following are key findings of the two-fluid, asymmetric research on MRX that is shown to be in striking agreement with measurements of electron and ion behavior by the space satellites and the conversion of magnetic energy to particle energy. Computer simulations aided these findings:

    • Electrons. The experiments demonstrated that electron current flows perpendicular, and not parallel as once thought, to the magnetic field. This flow is key to the conversion of magnetic energy in electrons that occurs in a narrow boundary layer called the “electron diffusion region” where rapid reconnection takes place. The finding is consistent with the recent MMS space measurements and new in the laboratory for asymmetric reconnection.

    • Ions. The ion current also flows perpendicular to the magnetic field as in the electron case, and likewise is key to the conversion of ion magnetic energy to particle energy. For ions, this conversion occurs in the wider “ion diffusion region” between converging plasmas and is a similarly recent finding about asymmetric reconnection in laboratory plasmas.

    The MRX experiments further studied different aspects of conversion in the symmetric and asymmetric cases. In symmetric reconnection, 50 percent of magnetic energy was previously found to be converted to ions and electrons, with one-third of the conversion affecting the electrons and two-thirds accelerating the ions. The total conversion rate remains roughly the same in the asymmetric case, as does the ratio of energy conversion for ions and electrons.

    PPPL researchers contributing to this study were Jongsoo Yoo, Will Fox, Jonathan Jara-Almote and Hantao Ji. Also contributing were physicists at the NASA Goddard Space Flight Center, Los Alamos National Laboratory, the Southwest Research Institute, and the universities of New Hampshire and Bergen in Bergen, Norway. Computer simulations were conducted at Los Alamos National Laboratory. Support for this work comes from DOE’s Office of Science, NASA, and the National Science Foundation.

    See the full article here .


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

    Stem Education Coalition


    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.

     
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