European Space Agency

European Space Agency

Royal Belgian Institute for Aeronomy

Royal Belgian Institute for Aeronomy

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um530 - evaluate the magnetic field vector

subroutine  um530(mpos, mb, ifail)
Parameters:

  • mpos [zgeo,in] :: geographic position in geocentric coordinates [GEO]

  • mb [zvec,out] :: magnetic field vector

  • ifail [integer4,out] :: error flag (see Diagnostics)

Description

The subroutine um530() evaluates the magnetic field vector at a geographic location. Before the first call to subroutine um530(), the magnetic field parameters have to be initialized. These parameters are stored in the common block uc140 but they can be modified with the help of the subroutines um510() and um520(). The subroutines um510() and um520() allow to select an internal geomagnetic field model (e.g. IGRF) and an external magnetic field (e.g. Tsyganenko), respectively. The geographic location mpos has to be provided in geocentric spherical coordinates. The subroutine um530() returns the spherical component and the intensity of the magnetic field vector. Note that the magnetic field vector is evaluated by the subroutine even when the error flag ifail is returned with the negative values -53002, -53003 and -53004. The diagnostics provided by the subroutine um530() are controlled by the parameters xrmin, xbmin, xtmin and xbmax stored in the common block uc192.

Diagnostics

  • -53001, position too deep inside the Earth

  • -53002, too small value of the magnetic field intensity

  • -53003, too large value of the geomagnetic latitude

  • -53004, too large value of the magnetic field intensity

  • -53005, incorrect value of the co-latitude

Common Blocks

Dependencies

Called by

Calls

See also

Reported Bugs

Examples

UNILIB/tags/v3.02