Verner, D. A., & Yakovlev, D. G. 1995, A&AS, 109, 125. 
Analytic fits for partial photoionization cross sections.
Table 1 `Fit parameters for partial photoionization cross sections'
Byte-per-byte description of file: table1.dat
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   Bytes Format  Units   Label        Explanations
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   1-  2  I2     ---     Z            Atomic number
   4-  5  I2     ---     N            Number of electrons
   7-  7  I1     ---     n            Principal quantum number of the shell 
   9-  9  I1     ---     l            Orbital quantum number of the subshell 
  11- 20  E10.4  eV      E_th         Subshell ionization threshold energy
  22- 31  E10.4  eV      E_0          Fit parameter
  33- 42  E10.4  Mb      \sigma_0     Fit parameter
  44- 53  E10.4  ---     y_a          Fit parameter
  55- 64  E10.4  ---     P            Fit parameter
  66- 75  E10.4  ---     y_w          Fit parameter
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