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Heating plasma to the ultra-high temperatures needed for fusion reactions requires more than turning the dial on a thermostat. Scientists consider multiple methods, one of which involves injecting electromagnetic waves into the plasma, the same process that heats food in microwave ovens. But when they produce one type of heating wave, they can sometimes simultaneously create another type of wave that does not heat the plasma, in effect wasting energy.

In response to the problem, scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have performed computer simulations confirming a technique that prevents the production of the unhelpful waves, known as slow modes, boosting the heat put into the and increasing the efficiency of the fusion reactions.

“This is the first time scientists have used 2D computer simulations to explore how to reduce slow modes,” said Eun-Hwa Kim, a PPPL principal research physicist and lead author of the paper reporting the results in Physics of Plasmas. “The results could lead to more efficient plasma heating and possibly an easier path to fusion energy.”

How do you find and measure nuclear particles, like antineutrinos, that travel near the speed of light?

Antineutrinos are the antimatter partner of a neutrino, one of nature’s most elusive and least understood subatomic particles. They are commonly observed near nuclear reactors, which emit copious amounts of antineutrinos, but they also are found abundantly throughout the universe as a result of Earth’s natural radioactivity, with most of them originating from the decay of potassium-40, thorium-232 and uranium-238 isotopes.

When an antineutrino collides with a proton, a positron and a neutron are produced—a process known as inverse beta decay (IBD). This event causes scintillating materials to light up, making it possible to detect these antineutrinos; and if they can be detected, they can be used to study the properties of a reactor’s core or Earth’s interior.

Imagine if we could take the energy of the sun, put it in a container, and use it to provide green, sustainable power for the world. Creating commercial fusion power plants would essentially make this idea a reality. However, there are several scientific challenges to overcome before we can successfully harness fusion power in this way.

Researchers from the U. S. Department of Energy (DOE) Ames National Laboratory and Iowa State University are leading efforts to overcome material challenges that could make commercial fusion power a reality. The research teams are part of a DOE Advanced Research Projects Agency-Energy (ARPA-E) program called Creating Hardened And Durable fusion first Wall Incorporating Centralized Knowledge (CHADWICK). They will investigate materials for the first wall of a fusion reactor. The first wall is the structure that surrounds the fusion reaction, so it bears the brunt of the extreme environment in the fusion reactor core.

ARPA-E recently selected 13 projects under the CHADWICK program. Of those 13, Ames Lab leads one of the projects and is collaborating alongside Iowa State on another project, which is led by Pacific Northwest National Laboratory (PNNL).

Atomic simulations deepen the mystery of how engineered materials known as refractory high-entropy alloys can suffer so little damage by radiation.

Refractory high-entropy alloys are materials made from multiple high-melting-point metals in roughly equal proportions. Those containing tungsten exhibit minimal changes in mechanical properties when exposed to continuous radiation and could be used to shield the crucial components of future nuclear reactors. Now Jesper Byggmästar and his colleagues at the University of Helsinki have performed atomic simulations that explore the uncertain origins of this radiation resistance [1]. The findings could help scientists design novel materials that are even more robust than these alloys in extreme environments.

The researchers studied a tungsten-based refractory high-entropy alloy using state-of-the-art simulations guided by machine learning. In particular, they modeled the main mechanism by which radiation can disrupt such an alloy’s atomic structure. In this mechanism, the incoming radiation causes one atom in the alloy to displace another atom, forming one or more structural defects. The team determined the threshold energy needed to induce such displacements and its dependence on the masses of the two involved atoms.

Through its commitment to international nuclear nonproliferation — a mission focused on limiting the spread of nuclear weapons and sensitive technology while working to promote peaceful use of nuclear science and technology — the United States maintains a constant vigilance aimed at reducing the threat of nuclear and radiological terrorism worldwide.

With extensive research into both basic and applied uranium science, as well as internationally deployed operational solutions, the Department of Energy’s Oak Ridge National Laboratory is uniquely positioned to contribute its comprehensive capabilities toward advancing the U.S. nonproliferation mission.

In 1943, seemingly overnight, ORNL emerged from a rural Tennessee valley as the site of the world’s first continuously operating nuclear reactor, in support of U.S. efforts to end World War II. ORNL’s mission soon shifted into peacetime applications, harnessing nuclear science for medical treatments, power generation and breakthroughs in materials, biological and computational sciences.

The LOREX experiment utilizes lorandite ore to gauge historical solar neutrino flux, revealing insights about the Sun’s development and climatic effects through advanced decay rate measurements.

The Sun, Earth’s life-sustaining powerhouse, generates immense energy through nuclear fusion while emitting a steady stream of neutrinos — subatomic particles that reveal its inner workings. While modern neutrino detectors shed light on the Sun’s current behavior, key questions remain about its stability over millions of years — a timeframe encompassing human evolution and major climate changes.

Addressing these questions is the mission of the LORandite EXperiment (LOREX), which depends on accurately determining the solar neutrino cross-section for thallium. An international team of scientists has now achieved this crucial measurement using the unique Experimental Storage Ring (ESR) at GSI/FAIR in Darmstadt. Their groundbreaking results, advancing our understanding of the Sun’s long-term stability, have been published in the journal Physical Review Letters.

A Sweden-based firm has launched a plasma confinement project to achieve commercially viable fusion energy.

The TauEB project by Novatron Fusion Group aims to revolutionize plasma confinement and energy containment in fusion reactors.

Novatron’s project will introduce a first-of-its-kind integration of three physical confinement techniques, which will include Magnetic Confinement, Ambipolar Plugging, and Ponderomotive Confinement.

Fusion energy research is being pursued around the world as a means of solving energy problems. Magnetic confinement fusion reactors aim to extract fusion energy by confining extremely hot plasma in strong magnetic fields.

Its development is a comprehensive engineering project involving many advanced technologies, such as , reduced-activation materials, and beam and wave heating devices. In addition, predicting and controlling the confined plasma, in which numerous charged particles and electromagnetic fields interact in complex ways, is an interesting research subject from a physics perspective.

To understand the transport of energy and particles in confined plasmas, theoretical studies, using supercomputers, and experimental measurements of plasma turbulence are being conducted.

Stars are born, live and die in spectacular ways, with their deaths marked by one of the biggest known explosions in the universe. Like a campfire needs wood to keep burning, a star relies on nuclear fusion—primarily using hydrogen as fuel—to generate energy and counteract the crushing force of its own gravity.

But when the fuel runs out, the outward pressure vanishes, and the star collapses under its own weight, falling at nearly the speed of light, crashing into the core and rebounding outward. Within seconds, the star is violently blown apart, hurling stellar debris into space at speeds thousands of times faster than the most powerful rocket ever built. This is a .

Astronomers aim to understand what types of stars produce different kinds of explosions. Do more result in brighter explosions? What happens if a star is surrounded by dust and gas when it explodes?

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