Pc3 pulsations during variable IMF conditions
نویسندگان
چکیده
Pc3 geomagnetic ®eld ̄uctuations detected at low latitude (L'Aquila, Italy) during the passage of a high velocity solar wind stream, characterized by variable interplanetary magnetic ®eld conditions, are analyzed. Higher frequency resonant ̄uctuations and lower frequency phenomena are simultaneously observed; the intermittent appearance and the variable frequency of the longer period modes can be well interpreted in terms of the variable IMF elements; moreover their polarization characteristics are consistent with an origin related to external waves propagating in antisunward direction. A comparison with simultaneous observations performed at Terra Nova Bay (Antarctica) provides additional evidence for a clear relationship between the IMF and Pc3 pulsations also at very high latitudes.
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