19 lines
589 B
Fortran
19 lines
589 B
Fortran
FUNCTION SGHE12(FR)
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C ===================
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C
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C Special formula for the photoionization cross-section from the
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C averaged <n=2> level of He I
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C
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INCLUDE 'IMPLIC.FOR'
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PARAMETER (C1=3.D0,C2=9.D0,C3=1.6D1,T15=1.D-15,
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* A1=6.45105D-18,A2=3.02D-19,A3=9.9847D-18,A4=1.1763673D-17,
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* A5=3.63662D-19,A6=-2.783D2,A7=1.488D1,A8=-2.311D-1,
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* E1=3.5D0,E2=3.6D0,E3=1.91D0,E4=2.9D0,E5=3.3D0)
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C
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X=FR*T15
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XX=LOG(FR)
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SGHE12=(C1*(A1/X**E1+A2/X**E2)+A3/X**E3+C2*(A4/X**E4+A5/X**E5)+
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* C1*EXP(A6+XX*(A7+XX*A8)))/C3
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RETURN
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END
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