magnetic fields tagged posts

Surprise finding: Discovering a previously unknown role for a source of Magnetic Fields

Physicists Jackson Matteucci and Will Fox with poster displaying their research.

Physicists Jackson Matteucci and Will Fox with poster displaying their research.

Feature describes unexpected discovery of a role the process that seeds magnetic fields plays in mediating a phenomenon that occurs throughout the universe and can disrupt cell phone service and knock out power grids on Earth. Magnetic forces ripple throughout the universe, from the fields surrounding planets to the gasses filling galaxies, and can be launched by a phenomenon called the Biermann battery effect. Now scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have found that this phenomenon may not only generate magnetic fields, but can sever them to trigger magnetic reconnection – a remarkable and surprising discovery.

The Biermann battery effect, a possible s...

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Astrophysicists Settle Cosmic Debate on Magnetism of Planets and Stars

This is a 3-D radiation magneto-hydrodynamic FLASH simulation of the experiment, performed on the Mira supercomputer at Argonne National Laboratory. The values demonstrate strong amplification of the seed magnetic fields by turbulent dynamo. Credit: Petros Tzeferacos/University of Chicago

This is a 3-D radiation magneto-hydrodynamic FLASH simulation of the experiment, performed on the Mira supercomputer at Argonne National Laboratory. The values demonstrate strong amplification of the seed magnetic fields by turbulent dynamo. Credit: Petros Tzeferacos/University of Chicago

Laser experiments verify ‘turbulent dynamo’ theory of how cosmic magnetic fields are created. By creating a hot turbulent plasma the size of a penny, that lasts a few billionths of a second, the researchers recorded how the turbulent motions can amplify a weak magnetic field to the strengths of those observed in our sun, distant stars, and galaxies...

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Magnetic fields can Calm Plasma instabilities, Simulations suggest

Magnetic perturbations in a fusion plasma are shown. Credit: Gerrit Kramer

Magnetic perturbations in a fusion plasma are shown. Credit: Gerrit Kramer

Physicists led by Gerrit Kramer at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have conducted simulations that suggest that applying magnetic fields to fusion plasmas can control instabilities known as Alfvén waves that can reduce the efficiency of fusion reactions. Such instabilities can cause quickly moving charged particles called “fast ions” to escape from the core of the plasma, which is corralled within machines known as tokamaks. Controlling these instabilities leads to higher temperatures within tokamaks and thus more efficient fusion processes.

“Controlling and suppressing the instabilities helps improve the fast-ion confinement and plasma performance,” said Kramer, a r...

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3D Simulations Illuminate Supernova Explosions

Magnetohydrodynamic turbulence powered by neutrino-driven convection behind the stalled shock of a core-collapse supernova simulation. This simulation shows that the presence of rotation and weak magnetic fields dramatically impacts the development of the supernova mechanism as compared to non-rotating, non-magnetic stars. The nascent neutron star is just barely visible in the center below the turbulent convection. Credit: Sean M. Couch, Michigan State University

Magnetohydrodynamic turbulence powered by neutrino-driven convection behind the stalled shock of a core-collapse supernova simulation. This simulation shows that the presence of rotation and weak magnetic fields dramatically impacts the development of the supernova mechanism as compared to non-rotating, non-magnetic stars. The nascent neutron star is just barely visible in the center below the turbulent convection. Credit: Sean M. Couch, Michigan State University

Michigan State University researchers are using Mira to perform large-scale 3D simulations of the final moments of a supernova’s life cycle...

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