Name

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    DEREDD

Purpose

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    Deredden stellar Stromgren parameters given for a value of E(b-y)

Explanation

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    See the procedure UVBYBETA for more info.

Calling Sequence

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    deredd, eby, by, m1, c1, ub, by0, m0, c0, ub0, /UPDATE

Inputs

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    Eby - color index E(b-y),scalar (E(b-y) = 0.73*E(B-V) )
    by - b-y color (observed)
    m1 - Stromgren line blanketing parameter (observed)
    c1 - Stromgren Balmer discontinuity parameter (observed)
    ub - u-b color (observed)
    These input values are unaltered unless the /UPDATE keyword is set

Outputs

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    by0 - b-y color (dereddened)
    m0 - Line blanketing index (dereddened)
    c0 - Balmer discontinuity parameter (dereddened)
    ub0 - u-b color (dereddened)

Optional Input Keywords

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    /UPDATE - If set, then input parameters are updated with the dereddened
          values (and output parameters are not used).

Revision History

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    Adapted from FORTRAN routine DEREDD by T.T. Moon
    W. Landsman STX Co. April, 1988
    Converted to IDL V5.0 W. Landsman September 1997