Quantitative Theory for Generation of 2-3 kHz Emissions beyond the Heliopause

Details Quantitative Theory for Generation of 2-3 kHz Emissions beyond the Heliopause Quantitative Theory for Generation of 2-3 kHz Emissions beyond the Heliopause

Dec 2002

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002agufmsh21a0481c&link_type=abstract

American Geophysical Union, Fall Meeting 2002, abstract #SH21A-0481

Physics

2124 Heliopause And Solar Wind Termination, 2139 Interplanetary Shocks, 7807 Charged Particle Motion And Acceleration, 7847 Radiation Processes, 7871 Waves And Instabilities

Scientific paper

Radio emissions observed at 2-3 kHz by the Voyager spacecraft are associated with global merged interaction regions (GMIRs) reaching the vicinity of the heliopause. A recent theory [Cairns and Zank, GRL, 29(7), 10.109/2001GL014112,2002] predicts that the radiation is generated in foreshock regions upstream of the GMIR shock, turning on when the shock enters a region primed with a superthermal electron tail beyond and near the heliopause nose. In this theory the tail is produced by ``lower hybrid-drive'' associated with pick-up ions. In this paper we combine a recent theory for type II solar radio bursts [Knock et al., JGR, 106, 25041, 2001] with the Cairns and Zank theory, resulting in a semianalytic, quantitative theory for the 2-3 kHz radiation. The new theory treats electron reflection and shock-drift acceleration at the shock, formation of electron beams in the foreshock, generation of Langmuir waves, and conversion of Langmuir energy into radiation near the fundamental and harmonic of the electron plasma frequency. The theory predicts the characteristics of electron beams and radio emissions throughout the foreshock, as well as the flux observed by a distant observer. We show that the new theory predicts (1) fluxes of fundamental radiation of order those observed (≈ 3x 10-17 W~m-2~Hz-1 for nominal shock and plasma parameters for the outer heliosheath, (2) the superthermal electron tail produced by lower hybrid-drive increases the fundamental flux by ≈ 2 orders of magnitude compared with predictions that neglect the tail, and (3) fundamental emission dominates harmonic emission. The latter two results confirm the theoretical predictions of Cairns and Zank [2002], while the first suggests that this theory is viable for generation of 2-3 kHz radiation beyond and near the heliopause.

Affiliated with

Also associated with

No associations

Rating

Quantitative Theory for Generation of 2-3 kHz Emissions beyond the Heliopause does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Quantitative Theory for Generation of 2-3 kHz Emissions beyond the Heliopause, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantitative Theory for Generation of 2-3 kHz Emissions beyond the Heliopause will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1435595