Substorm-associated VLF emissions with frequency drift observed in the premidnight sector

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

12

Atmospherics, Night Sky, Plasma Drift, Polar Substorms, Very Low Frequencies, Atmospheric Physics, Hiss, Radio Emission

Scientific paper

The characteristics of premidnight substorm-associated VLF emissions are examined on the basis of data obtained by the VLF/ELF campaign during November 1978 to February 1979 by means of the direction-finding measurements at two stations, Brorfelde in Denmark (L-value of about 3) and Chambon-la-Foret in France (L-value about 2) as well as ISIS satellite measurements. Two remarkable events have been analyzed, and the following main properties have emerged: (1) the emissions observed are of hiss type and are excited mainly within the plasmapause, (2) the emission activity is preceded by the development of two subsequent substorms, and (3) the emission frequency increases sharply at the first stage of the events and is followed by its subsequent gradual decrease. These properties of the temporal evolution of the wave spectrum are interpreted in terms of a quasi-linear electron cyclotron instability model for wave excitation. The initial frequency increase is believed to be due to a combined effect of L shell drift of energetic electrons injected during the first substorm and a decrease of a large-scale convection electric field during the development of the events. The subsequent frequency decrease may be related to the additional injection of energetic electrons due to the development of the second substorm.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Substorm-associated VLF emissions with frequency drift observed in the premidnight sector 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 Substorm-associated VLF emissions with frequency drift observed in the premidnight sector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Substorm-associated VLF emissions with frequency drift observed in the premidnight sector will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1181987

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.