CONTROL OF TERRESTRIAL LOW-FREQUENCY BURSTS BY SOLAR-WIND SPEED

Using WIND spacecraft data from the WAVES, SWE, and MFI experiments fo r the period from January through July, 1995, we show that the occurre nce of the terrestrial low frequency (LF) radio bursts is controlled p rimarily by the solar wind speed. A possible secondary factor in deter mining the occurrence of the bursts is the direction of the IMF in the x-y plane, with the 'toward' direction (B-y< 0) favored. The correlat ion with bulk speed suggests, on a gross scale, a viscous-like couplin g mechanism between the solar wind and the magnetosphere. In terms of the nature of the solar wind correlation, terrestrial LF bursts strong ly resemble the Earth's AKR and Jovian quasi-periodic bursts.