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Manuscript Title: Programs for computing LS and LSJ transitions from MCHF wave functions.
Authors: C.F. Fischer, M.R. Godefroid
Program title: MCHF_LSTR AND MCHF_LSJTR
Catalogue identifier: ACBB_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 64(1991)501
Programming language: Fortran.
Computer: VAX 11/780.
Operating system: VMS, Sun UNIX.
RAM: 153K words
Word size: 32
Peripherals: disc.
Keywords: Transition probabilities, Oscillator strengths, Line strengths, Transition energies, Electric dipole, Electric quadrupole, Magnetic dipole, Allowed transitions, Forbidden transitions, Atomic physics, Structure.
Classification: 2.1.

Subprograms used:
Cat Id Title Reference
ABZU_v1_0 MCHF_LIBRARIES CPC 64(1991)399

Nature of problem:
These programs are part of the MCHF atomic structure package [1] for bound state systems and evaluate transition data from MCHF wave function expansions. MCHF_LSTR performs non-relativistic calculations for E1 and E2 transitions between a pair of LS states. MCHF_LSJTR performs similar calculations for electric E1, E2,..., or magnetic M1, M2,...transitions between all LSJ states of two sets of expansions. Oscillator strengths, line strengths, transition energies, and transition probabilities are reported.

Solution method:
Given either LS or LSJ expansion coefficients for the wave functions, the radial functions and the MLTPOL.LST produced by MCHF_MLTPOL, the radial integrals occuring in the latter are integrated numerically, and the matrix element between atomic states is computed by summing the contributions from pairs of configuration states, weighted by their expansion coefficients.

Restrictions:
The dimensions of the problem are such that the sum of the number of configuration states in the initial and final state cannot exceed 400, the number of radial functions cannot exceed 60. At most two different overlap integrals may multiply a radial integral derived from a transition operator.

Unusual features:
The program allows for a limited degree of non-orthogonality between the orbitals of the initial and final states. The common core orbitals are assumed to be the same in both states.

Running time:
The CPU time required for the first case is 0.7 seconds for MCHF_LSTR and 1.7 seconds for MCHF_LSJTR on a SUN 3/160 with a floating point board. The second MCHF_LSJTR calculation required 4.0 seconds.

References:
[1] C. Froese Fischer, Computer Phys. Commun. 64(1991)369.