Jena Meinecke (SIMES Seminar)

Date(s) - Oct 6 2014
11:00 AM - 12:00 PM

Shasta Room, Bldg. 40, Room 361


Magnetic field amplification of laser-produced plasmas

Jena Meinecke – University of Oxford

We present the first laboratory measurements of magnetic field amplification in laser-produced plasmas to gain insight into the origins of magnetic fields in the Universe. Radiosynchroton emission and Faraday Rotation measurements have all revealed that the Universe is magnetised—from clusters to filaments to voids—implying that magnetic fields are essential players in the dynamics of luminous matter. The most widely accepted explanation for cosmic magnetogenesis is that small, primordial magnetic fields were generated, possibly from misaligned density and temperature gradients, and grew from some form of turbulent dynamo. Due to the advent of high-energy lasers, scientists are able to recreate conditions in the laboratory which are similar to those in the Universe. Using the Vulcan laser at the Rutherford Appleton Laboratory (UK), we have generated primordial magnetic fields via the Biermann Battery mechanism in laser-produced shock waves. By disturbing the shock front with a non-conducting, plastic grid, we created a turbulent plasma, allowing for stochastic tangling of magnetic fields. Induction coils measured ~2-3 times larger magnetic fields in turbulent structures, providing the first laboratory measurements of magnetic field amplification relevant to the supernova remnant Cassiopeia A. Additionally, we have measured magnetic field amplification in interpenetrating, laser-produced jets relevant to Herbig-Haro objects in the Orion and Veil molecular clouds.