A laboratory experiment to investigate auroral kilometric radiation emission mechanisms

• Published in: Journal of plasma physics Vol. 71; no. 5; pp. 665 - 674
• Main Authors: SPEIRS, D.C., VORGUL, I., RONALD, K., BINGHAM, R., CAIRNS, R.A., PHELPS, A.D.R., KELLETT, B.J., CROSS, A.W., WHYTE, C.G., ROBERTSON, C.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.10.2005
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; Fundamental aspects of astrophysics; Fundamental astronomy and astrophysics. Instrumentation, techniques, and astronomical observations; Magnetic fields; Magnetohydrodynamics and plasmas; Plasma physics; Aurorae; Electron beams; Laboratory investigations; Experimental method; Digital simulation; Magnetic moments; Instability; Auroral kilometric radiation; Magnetic compression; Experimental study; Earth pole
• ISSN: 0022-3778; 1469-7807
• DOI: 10.1017/S0022377804003459

If an initially mainly rectilinear electron beam is subject to significant magnetic compression, the conservation of the magnetic moment results in the ultimate formation of a horseshoe distribution in phase space. A similar situation occurs where particles are accelerated into the auroral region of the Earth's magnetic dipole. Such a distribution has been shown to be unstable to a cyclotron resonance maser type of instability and it has been postulated that this may be the mechanism required to explain the production in these regions of auroral kilometric radiation (AKR) and also possibly radiation from other astrophysical objects such as stars with a suitable magnetic field configuration. In this paper we describe a laboratory experiment to investigate the evolution of an electron beam subject to a magnetic compression of up to a factor of 30.