Thursday, December 6, 2012

The Expanding Palette of Fusion

More from the Fusion Power Associates meeting in Washington, D.C., concluding today:

A self portrait of fusion physicist Glen Wurden (from Los Alamos) taken in infrared wavelengths (3-5 microns), using a new state-of-the art infrared camera (FLIR Systems SC8303HD). This camera was tested on Alcator C-Mod in Sept 2012, and will be used as part of the  American/German collaboration on the new W7-X stellarator under construction in Germany, as a diagnostic to view the protective armor tiles on the vacuum vessel. The armor tiles get heated due to plasma-wall interactions.

Of hohlraums and plasmas and machines called “Z”

PPPL Director Stewart Prager described a host of scientific activities at the Lab during a talk at the annual Fusion Power Associates (FPA) meeting held in Washington, D.C. Steve Dean, the executive director of FPA, can be seen to his left. (Photo credit: Kitta MacPherson, PPPL Office of Communications)

By Kitta MacPherson

WASHINGTON, D.C. – What happens when the forces of fusion gather?

At the annual meeting of the Fusion Power Associates, held at the tony Capitol Hill Club in the shadow of the U.S. Capitol, there’s lots of talk about “plasmas” and “hohlraums” and of devices called stellarators and other machines with names like “Z.”

Starting yesterday and continuing through today, the leaders of fusion energy research in the U.S. from U.S. Department of Energy-funded laboratories, as well as from industry and publicly funded university programs, have been and will continue to line up and present, in rigorously timed 20-minute-long segments, the state of their art.  Differences in approaches to fusion from inertial confinement where pellets are zapped by lasers to magnetic confinement where a superhot gas is corked in a magnetic bottle are described. As competitive as the programs may be, all are regarded here as being under the aegis of fusion--part of the ecumenical approach of Steve Dean, the founder and executive director of the sponsoring group, the Fusion Power Associates.

The purpose of FPA, a non-profit foundation based in Gaithersburg, Md., is, according to its website, to “ensure the timely development and acceptance of fusion as a socially, environmentally, and economically attractive source of energy.” The meetings are designed to showcase management-level scientists and their technical achievements.

In the long narrow, federal style Eisenhower Room,  an observer in the space of several minutes can hear a full range of approaches to fusion from some of its best minds. Attendees can hear Mike Dunne, a leading scientist at the National Ignition Facility based at Lawrence Livermore National Laboratory in California, describe scientific advances in inertial fusion at the facility, pointing to diagrams showing cylindrical capsules called “hohlraums” that hold fusion fuel capsules. One can then listen to Stewart Prager, director of the Princeton Plasma Physics Laboratory, convey elements of progress in magnetic fusion. The Princeton lab is focusing on areas with breakthrough potential where the U.S. can lead, he said. And lest anyone think that PPPL is overly focused on a doughnut-shaped fusion reactor configuration known as a tokamak, Prager indicated his commitment to also support another configuration known as a stellarator. “We believe that stellarators are not a luxury item, we believe they are essential for fusion,” he said.

Observers at the meeting also can get a taste of the international.

Ned Sauthoff, director of the U.S. ITER program, talked about the importance of scientific research being conducted now to benefit ITER, a mammoth experimental fusion vessel under construction in Cadarache, France. “The science of ITER is happening now,” he said. “In order for it to succeed, you have to have a strong program that is related to things like burning plasmas.” The goal of ITER is to achieve 500 megawatts of fusion power. The giant tokamak is being designed to demonstrate the scientific and technological feasibility and safety features of fusion energy, Sauthoff said.

Tight budgets for domestic programs have leaders such as Miklos Porkolab, director of MIT’s Plasma Science Fusion Center, expressing concerns. “Vigorous research in the next decade is necessary on existing tokamak facilities with upgrades in heating and current drive power as well as advanced plasma diagnostics and tungsten plasma-facing components,” he said, adding that much physics remains to be explored on existing tokamaks in order to optimize ITER’s operation. The largest U.S. experimental magnetic fusion devices--at MIT, PPPL, and General Atomics--are complementary, he noted, and need sustained support.

In his presentation on fusion experiments at Los Alamos National Laboratory, Glen Wurden said he is worried about the impact of cuts to the domestic fusion program, especially in light of growing ITER commitments, and the survivability of the U.S. plasma physics and fusion research enterprise should there be additional cuts in future years. “We are dangerously approaching the tipping point,” he said.

Mark Herrmann, a physicist at Sandia National Laboratory, who was recognized for his research with an award from FPA, spoke with excitement about his work on a 10,000 square-foot experimental fusion device known as “Z”. “You have to be an optimist to be a fusion scientist,” he said with a smile.

Thursday, September 6, 2012

Dr. Z weighs in on sun killers

Could a supervillain destroy the sun that gives our planet life? When a writer for the science website Life’s Little Mysteries pondered that question, he turned to PPPL Deputy Director Michael Zarnstorff for his astrophysical expertise. Zarnstorff dismissed such notions as poisoning the sun’s fusion reaction, or siphoning off plasma to make the sun evaporate, as too far-fetched. But he said creating a black hole in the center of Old Sol might conceivably do the trick. To read how that would work, click here:
--- John Greenwald

Wednesday, May 23, 2012

U.S. Department of Energy's Plasma Science Center holds third annual meeting at PPPL

Graduate student Hongyue Wang discussed her work on plasmas in Hall thrusters with University of Michigan professor Mark Kushner during the third annual meeting of the U.S. Department of Energy's Plasma Science Center at PPPL. Wang, a student at Beihang University in Beijing, works with PPPL physicist Igor Kaganovich. Kushner directs the Plasma Science Center. (Photo credit: Elle Starkman, PPPL Office of Communications.)

More than 50 participants from a dozen U.S. research institutions gathered at the Princeton Plasma Physics Laboratory (PPPL) May 17-18 for the third annual meeting of the U.S. Department of Energy’s Plasma Science Center. The meeting featured papers on low-temperature plasmas, whose practical applications range from lighting to nanotechnology. Events at the session included a display of graduate student posters and a tour of PPPL.

Thursday, April 26, 2012

A flame is a plasma, after all, so PPPL joins a contest

Andrew Zwicker, a physicist at PPPL who heads science education, working with Aliya Merali.

More than 800 scientists. Nearly 5,000 students.

That’s how many people are involved in what ABC news anchor Diane Sawyer has called “the most inspired contest on the planet.”

In March, actor Alan Alda wrote a provocative editorial in the renowned journal Science. The title of his column, “The Flame Challenge,” described how he, as an 11-year-old, stared at a candle flame and wondered what it was. He wasn’t looking for overly simple answers – he wanted a step-by-step style of conversation that would lead to understanding. When he queried one teacher he thought he could approach, he received a disappointing answer. “What’s a flame?” he asked. “Oxidation,” she said. Many decades later, he sees this continuing failure to properly communicate science as a society-wide problem.

For years, he has been doing his part to address that problem by hosting “Scientific American Frontiers” on public television. In the show, Alda interviews scientists about their work, helping them explain their research to intelligent non-scientists. Now, as a member of the faculty at the Center for Communicating Science at the State University of Stony Brook on Long Island, Alda has launched his own experiment. He announced the Flame Challenge contest ( in Science, asking scientists, educators, and students to submit short videos, essays or effective communications by any other means to explain the simple question he asked as a boy.

Andrew Zwicker, a physicist at PPPL who heads science education, came up with a version of the answer, working with Aliya Merali. You can view it here:


Submissions, which were due on April 2, have poured in from all over the world. According to a story on the website of the Center for Communicating Science, participants submitted 822 entries  from the U.S. and 30 other countries. The entries range from a sentence to tomes and from poetry – one poem is written in the shape of a flame – to live-action videos with special effects. Once volunteer scientists screen the submissions for accuracy, the entries are being sent to schools where 11-year-olds at more than 130 schools will judge them. The finalists will be posted on, and the winner will be announced at the World Science Festival in New York, New York in early June.

-- Kitta MacPherson

Thursday, January 26, 2012

Wonder Weld


Engineers at the U.S. Department of Energy’s Princeton Plasma Physics Laboratory are using the process shown here to create a super-strong weld for the upgrade of a key component of the Lab’s experimental nuclear fusion reactor. The whirling steel tool in this demonstration joins two copper plates by heating them through friction to the consistency of wax. The roughened surface will be smoothed out in the finished product. Called “friction stir welding,” the process is critical to the upgrade of the test reactor that will enable Laboratory scientists to address major questions on the road to developing nuclear fusion as a safe, clean and virtually limitless source of energy for generating electricity. (Video by Edison Welding, Columbus, Ohio)

Friday, January 13, 2012

Snowflake Science

Let it snow! Scientists at the Princeton Plasma Physics Laboratory are using a novel device called a "snowflake divertor" to keep superhot gases from damaging the walls of a nuclear reactor during experiments to develop a safe, clean and virtually limitless fuel for producing electric power.