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Trapped Radiation ENvironment model Development


[ Name | Synopsis | Arguments | Description | Diagnostics | Common Blocks | Dependencies | See Also | Reported Bugs | Examples ]


    Subroutine UL240 - evaluate the Hilton's function


      RECORD /zlbl/ mlab
      INTEGER*4     ifail
      CALL UL240 (mlab, ifail)


    magnetic parameter of a field line segment [in/out]
    Error flag (see diagnostics) [out]


    The subroutine UL240 computes McIlwain's shell parameter L from the integral invariant I and the magnetic field intensity Bm at the mirror points. The parameter L is evaluated with the help of the Hilton's function. The inputs and result of the subroutine are passed through the argument mlab: mlab.finv and mlab.fbmp have to contain the values of I and Bm, respectively, and the value of L is stored in mlab.flmi. Note that both elements mlab.linv and mlab.lbmp have to be set to the value true.

    One should note that the behaviour of subroutine UL240 depends on the argument kmflg of the common block UC190. When kmflg is equal to 0 or 10, the magnetic dipole moment stored in the common block UC160 (argument gmagmo) is used to perform the evaluation of Hilton's function. When kmflg is equal to 1 or 11, the magnetic dipole moment of the current geomagnetic field model is used instead. The value of this last magnetic dipole moment is stored in argument mint.gmmo of the common block UC140.


  • Hilton, H.H., L parameter, a new approximation, JGR 76 (1971) 6952-6954


    -24001, value of the integral invariant I is negative
    -24002, value of the integral invariant I not specified
    -24003, value of B at the mirror point not specified

Common Blocks

    UC140, magnetic field description
    UC160, general constants
    UC190, control parameters, set 1


Called by

    UL220, get information on a magnetic field line segment
    UD317, trace a magnetic drift shell (new)
    UF411, search a local magnetic equator
    UF415, rebuild the labels of the field line



See also

    UC170, temporary magnetic field line
    UL230, evaluate the integral invariant coordinate I
    UL242, inverse the Hilton function

Reported Bugs