Mutiso, C.K. and Hughes, J.M. and Sivjee, G.G. and Pedersen, T. and Gustavsson, B. and Kosch, M.J. (2008) Previously unreported optical emissions generated during ionospheric heating. Geophysical Research Letters, 35 (L14103). pp. 1-6. ISSN 0094-8276
Abstract
Several radio-induced optical emissions were generated during an ionospheric heating experiment performed at the High Power Auroral Stimulation (HIPAS) facility near Two Rivers, Alaska. The O+ 732–733 nm and O(3 D o) 799.0 nm emissions, previously unreported from ionospheric heating experiments, were detected, in addition to the already documented O(3 P) 844.6 nm and O(5 P) 777.4 nm emissions. Maximum emission intensity was observed in the magnetic zenith, when the heater was transmitting continuous wave O-mode, at a frequency of 2.85 MHz. A modified Czerny-Turner grating spectrometer was used to acquire high resolution optical spectra of the induced emissions, which were synchronized to the heater duty cycle. Candidate mechanisms for the production of the radio-induced emissions, which occurred before the “double resonance” condition, are presented.