22 lines
639 B
Fortran
22 lines
639 B
Fortran
FUNCTION GFREE(T,FR)
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C ====================
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C
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C Hydrogenic free-free Gaunt factor, for temperature T and
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C frequency FR
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C
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INCLUDE 'PARAMS.FOR'
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THET=5040.4/T
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IF(THET.LT.4.E-2) THET=4.E-2
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X=FR/2.99793E14
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IF(X.GT.1) GO TO 10
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IF(X.LT.0.2) X=0.2
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GFREE=(1.0823+2.98E-2/THET)+(6.7E-3+1.12E-2/THET)/X
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RETURN
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10 C1=(3.9999187E-3-7.8622889E-5/THET)/THET+1.070192
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C2=(6.4628601E-2-6.1953813E-4/THET)/THET+2.6061249E-1
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C3=(1.3983474E-5/THET+3.7542343E-2)/THET+5.7917786E-1
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C4=3.4169006E-1+1.1852264E-2/THET
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GFREE=((C4/X-C3)/X+C2)/X+C1
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RETURN
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END
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