Historical research guide · 1100 · 2006
Dipole trapped spheromak in a prolate flux conserver
M. R. Brown · C. D. Cothran · J. Fung · M. Chang · J. Horwitz · M. J. Schaffer · J. Leuer · E. V. Belova
In one minute
Brown and colleagues report a spheromak formed in the Swarthmore Spheromak Experiment and trapped in a simple dipole magnetic field. They placed it in a copper flux conserver 0.4 metres in diameter and 0.6 metres long. That prolate vessel is ordinarily tilt-unstable, yet the plasma did not tilt during the discharge. The team characterized magnetic structure with probe arrays, ion temperature and flow with Doppler spectroscopy, and electron density with interferometry. They also ran three-dimensional magnetohydrodynamic simulations, which reproduced the configuration’s overall stability. This is a laboratory confinement result, not a claim about a cosmic object: a compact, self-organized plasma structure stayed stable in a deliberately awkward geometry when a dipole field and conducting boundary were part of the setup.
Connection
It gives a concrete laboratory bridge to the site’s plasma chapters: magnetic topology, flow, density, and stability were measured together instead of inferred from a single image.
From the source
The paper reports a spheromak formed in the Swarthmore Spheromak Experiment and trapped in a simple dipole magnetic field. The result concerns a laboratory plasma configuration.Publisher abstract, opening sentence
The spheromak was studied in a copper flux conserver 0.4 metres in diameter and 0.6 metres long. The abstract calls this prolate geometry tilt-unstable.Publisher abstract, apparatus description
The plasma did not tilt despite the prolate flux conserver. That observed behavior is the paper’s central stability result.Publisher abstract, stability observation
Magnetic probe arrays measured the magnetic structure B(r,t). Ion Doppler spectroscopy supplied ion-temperature and flow measurements, while interferometry measured electron density.Publisher abstract, diagnostics
The authors used three-dimensional magnetohydrodynamic simulations of the experimental configuration. They report that those simulations verified its gross stability.Publisher abstract, simulation result
The next useful comparison is explicit in the apparatus: vary the dipole field or boundary geometry, then compare the probe, Doppler, interferometer, and simulation records to see which part of the stabilization changes.Publisher abstract, dipole field, flux conserver, diagnostics, and 3D MHD simulation
The way in
https://doi.org/10.1063/1.2356690How to cite it
M. R. Brown, C. D. Cothran, J. Fung, M. Chang, J. Horwitz, M. J. Schaffer, J. Leuer, E. V. Belova (2006) Dipole trapped spheromak in a prolate flux conserver doi:10.1063/1.2356690