Controlled Studies of Whistler Wave Interactions with Energetic Particles in Radiation Belts

摘要

Over the past several years we have been conducting VLF wave injection experiments at Arecibo Observatory, Puerto Rico, guided by our theoretical and numerical analyses, to investigate whistler wave interactions with inner radiation belts as well as the ionospheric effects caused by precipitated energetic electrons. The whistler waves used in our experiments were launched from the 100 kW and 40.75 kHz transmitter code-named NAU, which is operated by the United States Navy at Aguada, Puerto Rico, about 52 km to the west of the Arecibo Observatory. This report focuses on experiments in which the Arecibo Incoherent Scatter Radar (ISR) and ionosonde monitored properties of local ionosphere on the night of January 1-2, 2006. We examine possible correlations between occurrences of nighttime E-region plasma line (PL) enhancements over Arecibo and 40.75 kHz NAU emissions. We find that the NAU radiations can propagate in whistler mode into the L = 1.35 inner radiation belts where gyroresonant interactions with trapped 390 keV electrons increase the precipitation and radar detection rates of enhanced plasma lines.