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Manuscript Title: A program to calculate internal conversion coefficients for all atomic shells without screening.
Authors: O. Dragoun, G. Heuser
Catalogue identifier: ABGF_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 2(1971)427
Programming language: Fortran.
Computer: CDC 3300.
Operating system: MSOS.
RAM: 5K words
Word size: 24
Keywords: Nuclear physics, Internal, Conversion, Coulomb, Screening, Gamma function, Hypergeometric series, Hypergeometric function, Activity detection.
Classification: 17.6.

Nature of problem:
The program calculates internal conversion coefficients for all atomic subshells from K up to Q1. The formulas used are based on an analytical solution of the Dirac equation for electrons in the pure Coulomb field of a point nucleus. The finite-nuclear-size correction is included. The conversion coefficients computed with this program and corrected approximately for atomic screening were found to be in good agreement with experiment. The method is especially useful in cases in which no precise conversion coefficients are available (outer atomic shells, low atomic numbers, high transition energies).

Solution method:
The gamma function of complex argument is evaluated using the asymptotic and recurrence formulas. The hypergeometric function of complex variables, 2F1(a,b; c;z), is computed from the hypergeometric series inside the circle of convergence and by an analytical continuation out- side this region.

The program was tested successfully for all atomic subshells (K...Q1), atomic numbers Z<= 100, for electric and magnetic multipoles with 1<= L <= 5 and for transition energies higher than the electron binding energy in the pure Coulomb field up to 17 MeV.

Running time:
The evaluation of the K-shell conversion coefficient takes about two to six seconds on the CDC 3300. To calculate the P5 subshell conversion coefficient for the 2**5 pole electric transition requires about 70 seconds.