27 lines
733 B
Fortran
27 lines
733 B
Fortran
SUBROUTINE GFREED(ID,FR,CH,GFR,GFRD)
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C ====================================
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C
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C Hydrogenic free-free Gaunt factor (GFR) and its derivative (GFRD)
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C for depth ID, frequency FR, and charge CH
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C
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INCLUDE 'IMPLIC.FOR'
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INCLUDE 'BASICS.FOR'
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INCLUDE 'MODELQ.FOR'
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PARAMETER (C14=2.997925D14,
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* XMIN=0.2D0,
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* XMINI=UN/XMIN)
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C
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X=C14*CH/FR
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IF(X.LT.UN) THEN
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GFR=((GF4(ID)*X-GF3(ID))*X+GF2(ID))*X+GF1(ID)
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GFRD=((GF4D(ID)*X-GF3D(ID))*X+GF2D(ID))*X+GF1D(ID)
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ELSE IF(X.LT.XMINI) THEN
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GFR=GF0(ID)+GF5(ID)*X
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GFRD=GF0D(ID)+GF5D(ID)*X
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ELSE
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GFR=GF6(ID)
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GFRD=GF6D(ID)
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END IF
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RETURN
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END
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