Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] adkm_v1_0.gz(20 Kbytes)
Manuscript Title: A program for coupled-channels calculations with all order couplings for heavy-ion fusion reactions.
Authors: K. Hagino, N. Rowley, A.T. Kruppa
Program title: CCFULL
Catalogue identifier: ADKM_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 123(1999)143
Programming language: Fortran.
Computer: DEC.
Operating system: UNIX.
Keywords: Nuclear physics, Heavy ion subbarrier, Fusion reactions, Coupled-channel, Equations, Higher order coupling, No-coriolis, Approximation, Incoming wave boundary, Condition, Fusion cross section, Mean angular momentum, Spin distribution, Fusion barrier, Distribution, Multi-dimensional, Quantum tunnelling.
Classification: 17.7.

Nature of problem:
It has by now been well established that fusion reactions at energies near and below the Coulomb barrier are strongly influenced by couplings of the relative motion of the colliding nuclei to several nuclear intrinsic motions. Recently, precisely measured fusion cross sections have become available for several systems, and a distribution of the Coulomb barrier, which is originated from the channel couplings, have been extracted. It has been pointed out that the linear coupling approximation, which has often been used in coupled-channels calculations, is inadequate in order to analyze such high precision experimental data. The program CCFULL solves the coupled-channels equations to compute fusion cross sections and mean angular momenta of compound nucleus, taking into account the couplings to all orders.

Solution method:
CCFULL directly integrates coupled second order differential equations using the modified Numerov method. The incoming wave boundary condition is employed and a barrier penetrability is calculated for each partial wave. Nuclear coupling matrix elements are evaluated by using the matrix diagonalisation method once the physical space has been defined.

The program is best suited for systems where the number of channels which strongly couple to the ground state is relatively small and where multi-nucleon transfer reactions play less important role compared with inelastic channels. It also relies on an assumption that the fusion process is predominantly governed by quantum tunnelling over the Coulomb barrier. This assumption restricts a system which the program can handle to that where the sum of the charge of the projectile and the target nuclei Zp + ZT is larger than around 12 and the charge product ZpZT less than around 1800. For most of experimental data which were measured to aim to extract fusion barrier distributions, this condition is well satisfied. The program also treats a vibrational coupling in the harmonic limit and a rotational coupling with a pure rotor. The program can be modified for general couplings by directly providing coupling strengths and excitation energies.

Running time:
A few seconds for input provided. The computer time depends strongly upon the number of channels to be included. It will considerably increase if one wishes to include a large number of channels, as for instance 20.