oa Geomagnetic Micropulsarions at a Low Latitude Station in Brazil (L=1.19)

This work presents a study on geomagnetic micropulsations at Santa Maria (27°S, 53 ° W) situated near the center of the South Atlantic Anomaly in Brazil. The geomagnetic field measurements were done by a very sensitive low noise fluxgate magnetometer; the data for the period March-May 1991 were analyzed using standard power spectrum Fourier techniques. From the power spectrum and polarization characteristics observed for Pc 3 and Pc 4 pulsations in selected quite days, it seems that Santa Maria is situated beyond the range of the Appleton Equatorial Anomaly Region. The results are comparable to those of other low-latitude stations.