Classification of IMF Directional Discontinuities
Date: 25 November 2004
Satellite: Cluster
Depicts: Scatter plot of directional discontinuities
Copyright: ESA
Scatter plot based on normal estimates from triangulation (red squares) and Cluster 4 MVA (black diamonds). All Directional Discontinuities (DDs) with λ2/λ3>2 at the location of Cluster 4 are considered. The classification of the DDs into the two types of discontinuity (Rotational:RD and Tangential:TD) is as follows:
- DDs with a large relative change in field magnitude (|[B]|/ Bmax>0.2) and small magnetic field component perpendicular to the plane of discontinuity (|Bn|/Bmax<0.4) are TDs
- DDs with (|[B]|/Bmax<0.2) and (|Bn|/Bmax>0.4) are RDs
- Those with small |[B]| and small |Bn| could be both RDs or TDs and are therefore called EDs (Either Discontinuities)
Note, that using triangulation not a single DD falls into the RD category.
Last Update: 1 September 2019
