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Trapped Radiation ENvironment model Development

UT998

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

Name

    Subroutine UT998 - evaluate the magnetic field vector and the normal to the field line

Synopsis

 
        RECORD /zgeo/ mgp
        REAL*8        rc
        RECORD /zvec/ mnr
        RECORD /zvec/ mb
        INTEGER*4     ifail    
        
        CALL UT998 (mgp, rc, mnr, mb, ifail)
 

Arguments

    mgp
    Geographic location [in]
    rc
    Radius of curvature [out]
    mnr
    Vector normal to the magnetic field line [out]
    mb
    Magnetic field vector [out]
    ifail
    Error flag (see diagnostics) [out]

Description

    The subroutine UT998 evaluates for a given geographic location the magnetic field vector and the vector normal to the magnetic field line passing through the point. Note that the subroutine makes use of the common block UC170 without corrupting the data already present in the common block. The norm of the normal vector is inversely proportional to the radius of curvature.

    The magnetic field vector mb is correctly returned by the subroutine, even when the value of the error flag ifail is equal to -99801 or -99802. When the error flag ifail is equal to -99804, only an approximated value of the normal vector mnr is returned.

History

    The error flags -99802 to -99804 where not generated in version 2.02 and earlier.

Diagnostics

    -99801, not enough place in common UC170
    -99802, not able to evaluate the normal vector mnr
    -99803, not able to compute the magnetic field vector mb
    -99804, uncertainties occured in the evaluation of the normal vector mnr

Common Blocks

    UC160, general constants
    UC170, temporary magnetic field line

Dependencies

Called by

    None

Calls

    UF423, Runge Kutta step
    UF425, evaluate the curvature of the field lines
    UM530, evaluate the magnetic field vector
    UT999, radius of curvature in a dipolar magnetic field

See also

    None

Reported Bugs

    None

Examples

    None