Centre for
SPACE PHYSICS
Centre for Space Physics

EMIC Waves in the Magnetosphere

 

EMIC waves are usually in the Pc1-2 bands and are associated with ions that gyrate around the magnetic field - ion cyclotron waves. Studies of Pc1-2 waves have been undertaken near Davis, Antarctica using a small network of magnetometers located in a square arrangement of side 120-150km.

Direction of arrival determinations on daytime quasi-structured and unstructured Pc1-2 emissions show they are associated with sources on closed field lines in the outer magnetosphere. This boundary region just inside the magnetopause may also be the origin of a prenoon Pc1-2 band, possibly a consequence of electromagnetic ion cyclotron wave (EMIC) generation resulting from ion injection into the magnetosphere from the dayside cleft. It has also been shown that these waves may propagate over short distances (< 500 km) but do not propagate in the ionospheric F2 region waveguide.