The phase structure of very low latitude ULF waves across dawn

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

5

Magnetospheric Physics: Magnetosphere-Inner, Magnetospheric Physics: Magnetosphere/Ionosphere Interactions, Magnetospheric Physics: Mhd Waves And Instabilities, Magnetospheric Physics: Numerical Modeling

Scientific paper

Ultralow frequency (ULF) waves at the geomagnetic equator are studied by using a small magnetometer array and a one-dimensional electromagnetic wave model. Most ULF waves observed at low latitudes have been associated with shear Alfven mode hydromagnetic resonances in the plasmasphere. Near the equator it is difficult to excite these resonances, and the wave activity is attributed to fast mode waves. The phase difference data recorded at longitudinally spaced, equatorial magnetometers shows a marked change around dawn when one station is sunlit while the other is still in darkness. The phase structure with latitude also shows large phase shifts near the equator, in agreement with previous studies. A model of ULF wave propagation through the equatorial ionosphere is presented and used to compare with the observed amplitude and phase properties. It is shown that the observed frequencies are in the vicinity of the wave cutoff frequency where the phase structure becomes complicated. For frequencies above the cutoff, the phase structure across dawn is directly related to dawn-associated changes in electron density in the ionosphere.

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

The phase structure of very low latitude ULF waves across dawn 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 The phase structure of very low latitude ULF waves across dawn, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The phase structure of very low latitude ULF waves across dawn will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-801699

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