Field-aligned currents and magnetospheric generator in experiments on a laser-produced plasma flowing around a magnetic dipole

• Published in: Cosmic research Vol. 52; no. 4; pp. 278 - 288
• Main Authors: Shaikhislamov, I. F., Antonov, V. M., Zakharov, Yu. P., Boyarintsev, E. L., Melekhov, A. V., Posukh, V. G., Ponomarenko, A. G.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.07.2014; Springer Nature B.V
• Subjects: Astronomy; Astrophysics and Astroparticles; Astrophysics and Cosmology; Physics; Physics and Astronomy; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Cosmic Research; Field Align Current; Solar Wind; Rogowski Coil; Solar Wind Velocity
• ISSN: 0010-9525; 1608-3075
• DOI: 10.1134/S001095251404008X

A laboratory experiment on modeling the magnetospheric generator of the field-aligned currents and the Earth’s transpolar potential in the absence of IMF is illustrated. The measurements of the total field-aligned current in the generator shorted mode and the transpolar potential in the circuit disconnection mode made it possible to determine the generator internal resistance. A model that explains the saturation current and internal resistance by the feedback between the field-aligned current and plasma flank motions has been proposed. This feedback is described through the effective resistance, which is proportional to the flow rate and the ratio of the boundary layer to the dimension of the magnetosphere. For the experimental conditions, the calculated generator resistance was in good agreement with the measured value. The estimates for the Earth’s magnetosphere indicate that the MHD generator internal resistance in the boundary layer is usually much lower than the reverse integral conductivity of the ionosphere.