Ground based observations of Pi2 pulsation in the terrestrial magnetic field

• Main Author: Nordström, Pontus
• Format: Bachelor Thesis
• Language: English
• Published: KTH, Rymd- och plasmafysik 2007
• Subjects: Fusion; Plasma and Space Physics; plasma och rymdfysik; SANAE; Antarc*; Antarctica
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91913

In this thesis ground-based observations of the terrestrial magnetic field have been used to studythe characteristics of a special type of magnetospheric pulsation called Pi2. The magnetic fielddata used was observed by the SANAE pulsation magnetometer, located at Antarctica. Severalcharacteristics of the pulsations have been examined for 137 events. For all the events aninjection of energetic particles could be seen simultaneously in the magnetosphere, which is anindication of a substorm onset. The particle injection was confirmed by data from theLANL/SOPA electron flux satellites, located in geosynchronous orbits at 6.6 RE height. Themain frequency of the events was concentrated in the lower part of the defined Pi2 range (7-25mHz) with a mean of 11.3 mHz. The polarisation parameters and the rate of damping wereexamined for 20 clear events. The damping increment had typical values of 0.05-2.Thepolarisation azimuth was directed in the North-East/South-West direction for most of the eventsand the sense of polarisation showed a transition from counter clockwise before 0200 local timeto clockwise afterward.