Azimuthal propagation of Pc5 geomagnetic field pulsations in the southern polar cap

• Published in: Advances in Space Research
• Main Authors: Lepidi, S., Cafarella, L., Pietrolungo, M., Santarelli, L.
• Other Authors: Lepidi, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Cafarella, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Pietrolungo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Santarelli, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2011
• Subjects: (2784) Solar wind-magnetosphere interactions; (2776) Polar cap phenomena; (2752) MHD waves and instabilities; 04. Solid Earth::04.05. Geomagnetism::04.05.02. Geomagnetic field variations and reversals; Antarctic; Dumont d’Urville; Mario Zucchelli; Mario Zucchelli Station; Antarc*
• Online Access: http://hdl.handle.net/2122/7024; https://doi.org/10.1016/j.asr.2010.10.027

A statistical analysis of low frequency geomagnetic fluctuations at the two Antarctic stations Mario Zucchelli Station (geographic coordinates: 74.7 S, 164.1 E; corrected geomagnetic coordinates: 80.0 S, 306.8 E) and Dumont D’Urville (geographic coordinates: 66.7 S, 140.0 E; corrected geomagnetic coordinates: 80.4 S, 236.0 E) is shown. The analysis focuses on power spectra, coherence and phase difference between the stations, which are both located in the polar cap, with a 5-h magnetic local time displacement along a geomagnetic parallel; in this situation, the phase difference between geomagnetic fluctuations indicates the direction of their azimuthal propagation. Coherent fluctuations have been found to occur preferably when both stations are on the same side (dawnward or duskward) with respect to the polar cusp; moreover, around local magnetic midnight, they occur essentially during open magnetospheric conditions. The phase difference for coherent fluctuations indicates a propagation direction away from local geomagnetic noon and midnight. Also the analysis of three individual pulsation events, occurring at different times during the day, is shown; they are characterized at the two stations by simultaneous, coherent fluctuations, whose phase difference finds correspondence with the statistical behaviour. 2010 COSPAR. Published by Elsevier Ltd. All rights reserved. Published 966-977 1.6. Osservazioni di geomagnetismo JCR Journal restricted