Geomagnetic Micropulsations Measurements At The Ferraz Brazilian Antarctic Station: Preliminary Results

The measurement of temporal variations is very important for understanding the behavior of the earth’s<br>magnetic field and its relation with sun’s activity. This work shows some results on the occurrence of<br>geomagnetic micropulsations as measured at the Ferraz Brazilian Antarctic Station - EACF (62°S, 58.4°W). This<br>station is situated near the southern border of the South Atlantic Magnetic Anomaly. The micropulsation events<br>were chosen from the geomagnetic data measured during 1993, 1994 and 1997. The geomagnetic<br>instrumentation included a high sensitivity ring core three-axis (H, D, Z) fluxgate magnetometer and a pair of<br>magnetic coils installed at a remote site. The results obtained from the data analysis show the occurrence of<br>Pc1, Pc2, Pc3, Pc4 and Pc5 micropulsations in the geomagnetic spectra observed at Ferraz. It seems that the<br>geomagnetic micropulsation spectra observed at Ferraz may have an important contribution from the<br>precipitation of Van Allen’s belts energetic particles into the atmosphere.