Tag Archives: plasma

Researchers hit milestone in accelerating particles with plasma

Technique is powerful, efficient enough to drive future particle accelerators

Researchers from UCLA and the Department of Energy’s SLAC National Accelerator Laboratory have shown that a promising technique for accelerating electrons on waves of plasma is efficient enough to power a new generation of shorter, more economical accelerators. This could greatly expand their use in areas such as medicine, national security, industry and high-energy physics research. (more…)

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A Path toward More Powerful Tabletop Accelerators

Laser light needn’t be as precise as previously thought to drive new breed of miniature particle accelerators, say Berkeley Lab researchers.

Making a tabletop particle accelerator just got easier. A new study shows that certain requirements for the lasers used in an emerging type of small-area particle accelerator can be significantly relaxed. Researchers hope the finding could bring about a new era of accelerators that would need just a few meters to bring particles to great speeds, rather than the many kilometers required of traditional accelerators. The research, from scientists at the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab), is presented as the cover story in the May special issue of Physics of Plasmas. (more…)

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Laser Instrument on NASA Mars Rover Tops 100,000 Zaps

NASA’s Curiosity Mars rover has passed the milestone of 100,000 shots fired by its laser. It uses the laser as one way to check which chemical elements are in rocks and soils.

The 100,000th shot was one of a series of 300 to investigate 10 locations on a rock called “Ithaca” in late October, at a distance of 13 feet, 3 inches (4.04 meters) from the laser and telescope on rover’s mast. The Chemistry and Camera instrument (ChemCam) uses the infrared laser to excite material in a pinhead-size spot on the target into a glowing, ionized gas, called plasma. ChemCam observes that spark with the telescope and analyzes the spectrum of light to identify elements in the target. (more…)

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Rocket powered by nuclear fusion could send humans to Mars

Human travel to Mars has long been the unachievable dangling carrot for space programs. Now, astronauts could be a step closer to our nearest planetary neighbor through a unique manipulation of nuclear fusion, the same energy that powers the sun and stars.

University of Washington researchers and scientists at a Redmond-based space-propulsion company are building components of a fusion-powered rocket aimed to clear many of the hurdles that block deep space travel, including long times in transit, exorbitant costs and health risks. (more…)

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‘Sideline quasars’ helped to stifle early galaxy formation, says CU study

University of Colorado Boulder astronomers targeting one of the brightest quasars glowing in the universe some 11 billion years ago say “sideline quasars” likely teamed up with it to heat abundant helium gas billions of years ago, preventing small galaxy formation.

CU-Boulder Professor Michael Shull and Research Associate David Syphers used the Hubble Space Telescope to look at the quasar — the brilliant core of an active galaxy that acted as a “lighthouse” for the observations — to better understand the conditions of the early universe. The scientists studied gaseous material between the telescope and the quasar with a $70 million ultraviolet spectrograph on Hubble designed by a team from CU-Boulder’s Center for Astrophysics and Space Astronomy. (more…)

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Measuring Table-Top Accelerators’ State-of-the-Art Beams

Studies by Berkeley Lab scientists of electron beam quality in laser plasma accelerators include novel tests for slice-energy spread

Part Two: Slicing through the electron beam

Wim Leemans of Berkeley Lab’s Accelerator and Fusion Research Division heads LOASIS, the Laser and Optical Accelerator Systems Integrated Studies, an oasis indeed for students pursuing graduate studies in laser plasma acceleration (LPA). Among the most promising applications of future table-top accelerators are new kinds of light sources, in which their electron beams power free electron lasers.

“If our LPA electron bunches had good enough quality for free electron lasers – and were really only femtoseconds long – we should see a particular kind of radiation called coherent optical transition radiation, or COTR,” Leemans says. “So I assigned my doctoral student Chen Lin, a graduate of Peking University and now a postdoc there, to find it.” (more…)

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Mug Handles Could Help Hot Plasma Give Lower-Cost, Controllable Fusion Energy

Researchers around the world are working on an efficient, reliable way to contain the plasma used in fusion reactors, potentially bringing down the cost of this promising but technically elusive energy source. A new finding from the University of Washington could help contain and stabilize the plasma using as little as 1 percent of the energy required by current methods.

“All of a sudden the current energy goes from being almost too much to almost negligible,” said lead author Thomas Jarboe, a UW professor of aeronautics and astronautics. He presents the findings this week at the International Atomic Energy Association’s 24th annual Fusion Energy Conference in San Diego. (more…)

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First Stars, Galaxies Formed more Rapidly than Expected

Analysis of data from the National Science Foundation’s South Pole Telescope, for the first time, more precisely defines the period of cosmological evolution when the first stars and galaxies formed and gradually illuminated the universe. The data indicate that this period, called the epoch of reionization, was shorter than theorists speculated — and that it ended early.

“We find that the epoch of reionization lasted less than 500 million years and began when the universe was at least 250 million years old,” said Oliver Zahn, a postdoctoral fellow at the Berkeley Center for Cosmological Physics at the University of California, Berkeley, who led the study. “Before this measurement, scientists believed that reionization lasted 750 million years or longer, and had no evidence as to when reionization began.” (more…)

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