On the envelope soliton below the H+ gyrofrequency in low auroral region
2002 (English)In: Astrophysics and Space Science, ISSN 0004-640X, E-ISSN 1572-946X, Vol. 282, no 2, 421-432 p.Article in journal (Refereed) Published
Two envelope soliton events below the H+ gyrofrequency with localized density depletionwere discovered in low auroral region (∼ 1760 km) by Freja satellite. These events werecorrelated in time with the observations of the ratio of oxygen ion density to hydrogen ion densitysharp increase and the electrons energization. These envelope solitons have a characteristic frequencyat ∼ 180–190 Hz, which are obviously different from the electron-ion lower hybrid wave frequencyand the helium ion gyrofrequency in low auroral plasma, but it is close to the resonance frequency ofhydrogen ion-oxygen ion hybrid wave. A modulational instability model of an ion-ion hybrid wavehas been discussed here. It is found that the envelope soliton below the H+ gyrofrequency in lowauroral region may be generated by this modulational instability on condition that the local oxygenion density is larger than the local hydrogen ion density.
Place, publisher, year, edition, pages
2002. Vol. 282, no 2, 421-432 p.
IdentifiersURN: urn:nbn:se:kth:diva-85332DOI: 10.1023/A:1020823804941ISI: 000178929400006ScopusID: 2-s2.0-0141570739OAI: oai:DiVA.org:kth-85332DiVA: diva2:499724
QC 201311212012-02-132012-02-132013-11-21Bibliographically approved