Colloquium - Don Lamb (University of Chicago) - Studying the Turbulent Amplification of Magnetic Fields in Laboratory and Astrophysical Plasmas Using High-Intensity Laser Experiments

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Don Lamb
April 7, 2015
4:00PM - 5:00PM
Location
1080 Physics Research Building - Smith Seminar Room - reception at 3:45pm in the Atrium

Date Range
Add to Calendar 2015-04-07 16:00:00 2015-04-07 17:00:00 Colloquium - Don Lamb (University of Chicago) - Studying the Turbulent Amplification of Magnetic Fields in Laboratory and Astrophysical Plasmas Using High-Intensity Laser Experiments

Magnetic fields are ubiquitous in the universe, but the origin of these fields is not fully understood.  Cosmologists and astrophysicists have proposed a variety of ways in which small seed magnetic fields could be created.  It is widely thought that the much larger values of the cosmic magnetic fields that we observe are a result of the amplification of these seed fields by the nonlinear turbulent dynamo mechanism.  However, this mechanism has never been demonstrated in the laboratory.  We describe experiments we conducted on the Vulcan laser at the Rutherford-Appleton Laboratory, which demonstrate the amplification of magnetic fields by turbulence.  We then describe accepted experiments on the Omega laser and the National Ignition Facility that are designed to demonstrate the amplification of magnetic fields by the nonlinear turbulent dynamo mechanism – a great challenge of experimental plasma physics.  We highlight the critical role of the validated simulations we have done using the FLASH code in the design, analysis, and interpretation of these experiments.

1080 Physics Research Building - Smith Seminar Room - reception at 3:45pm in the Atrium Department of Physics physics@osu.edu America/New_York public
Description

Magnetic fields are ubiquitous in the universe, but the origin of these fields is not fully understood.  Cosmologists and astrophysicists have proposed a variety of ways in which small seed magnetic fields could be created.  It is widely thought that the much larger values of the cosmic magnetic fields that we observe are a result of the amplification of these seed fields by the nonlinear turbulent dynamo mechanism.  However, this mechanism has never been demonstrated in the laboratory.  We describe experiments we conducted on the Vulcan laser at the Rutherford-Appleton Laboratory, which demonstrate the amplification of magnetic fields by turbulence.  We then describe accepted experiments on the Omega laser and the National Ignition Facility that are designed to demonstrate the amplification of magnetic fields by the nonlinear turbulent dynamo mechanism – a great challenge of experimental plasma physics.  We highlight the critical role of the validated simulations we have done using the FLASH code in the design, analysis, and interpretation of these experiments.