European Space Agency

Royal Belgian Institute for Aeronomy

uc120 - magnetic field line

type  uc120

Synopsis

INCLUDE 'unilib.h'

COMMON /UC120/ nbrfl, kurfl, mfl

INTEGER*4   nbrfl, kurfl
TYPE(zfln)  mfl(nx120)

Arguments

nbrfl

Number of field lines already computed

kurfl

Indice of the current field line

mfl

Description of the field line segments. Each indice corresponds to a field line. (zfln(nx120))

Description

The common block uc120 is part of a set of three common blocks:

• uc110, magnetic drift shell description;

• uc120, magnetic field line description;

• uc130, set of magnetic field line segments.

This set of common blocks is used to store a magnetic drift shell which is defined by a set of magnetic field line segments. The common block uc120 includes a global description of each field line segment as well as indices which points into the common block uc130.

The argument nbrfl indicates the number of magnetic field line segments included in the drift shell. For each segment, the geographic positions of the local magnetic equator (mfl%equat, and eventually of the foot points, mfl%footpn, mfl%footps), pointers to the eastern next and western previous segments (mfl%keast, mfl%kwest) and pointers to argument mseg of the common block uc130 (mfl%ind) are included in the description of each field line segment. The geographic position of the mirror points can be retrieved with the help of the pointers mfl%ind%jmirpn and mfl%ind%jmirps. Note that the common block uc170 has a similar structure (argument mlin).

Dependencies

Used by

• ud315 - search the mirror point with the lowest altitude

  nbrfl and mfl

• ud316 - Search the equatorial point with the lowest magnetic field intensity

  nbrfl, mfl()%equat, mfl()%keast

• ud317 - trace a magnetic drift shell

  mfl()%equat, mfl()%kwest

• ud319 - transfer a field line segment from common block uc170 to uc130

  nbrfl and mfl

• ud320 - evaluate a double time integral over a drift shell

  kurfl, mfl()%kwest, mfl()%keast, mfl()%equat%coord, mfl()%equat%b%dnrm, mfl()%drift and mfl()%ind

• ud331 - evaluate the magnetic flux through a spherical cap

  mfl

• ut985 - transfer a field line of the drift shell to IDL

  nbrfl and mfl

• ut992 - print the magnetic drift shell

  nbrfl and mfl

• ut993 - Store a magnetic field drift shell

  nbrfl and mfl

Modified by

• ud319 - transfer a field line segment from common block uc170 to uc130

  nbrfl, kurfl and mfl

• ud320 - evaluate a double time integral over a drift shell

  kurfl

• ud331 - evaluate the magnetic flux through a spherical cap

  kurfl

• ut990 - initialize the UNILIB library

  nbrfl and kurfl

See also

• uc110 - magnetic drift shell

• uc130 - magnetic field line segments

Examples

None

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UNILIB/tags/v3.02