A program to compute exact hydrogenic radial integrals, oscillator strengths, and Einstein coefficients, for principal quantum numbers up to n≈1000

Dy Hoang-Binh (1)

1 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique

An exact expression for the dipole radial integral of hydrogen has been given by Gordon [Ann. Phys. 2 (1929) 1031]. It contains two hypergeometric functions F(a,b;c;x), which are difficult to calculate directly, when the (negative) integers a, b are large, as in the case of high Rydberg states of hydrogenic ions. We have derived a simple method [D. Hoang-Binh, Astron. Astrophys. 238 (1990) 449], using a recurrence relation to calculate exactly F, starting from two initial values, which are very easy to compute. We present here a numerical code using this method. Program summaryTitle of program: ba5.f Catalogue identifier: ADUU Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADUU Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computers: all computers with a Fortran 77 compiler Operating system used: MacOS 9.0 Programming language used: Fortran 77 No. of lines in distributed program, including test data, etc.: 424 No. of bytes in distributed program, including test data, etc.: 2721 Distribution format: tar.gz Nature of physical problem: Exact calculation of atomic data. Method of solution: Use of recursion relation. Typical run time: 2 s

Domaines: Astrophysique [astro-ph]

Dy Hoang-Binh. A program to compute exact hydrogenic radial integrals, oscillator strengths, and Einstein coefficients, for principal quantum numbers up to n≈1000. Computer Physics Communications, 2005, 166, pp.191-196. ⟨10.1016/j.cpc.2004.11.005⟩. ⟨hal-03742454⟩