A C-code for the double folding interaction potential for reactions involving deformed target nuclei

Abstract

We present a C-code designed to obtain the interaction potential between a spherical projectile nucleus and an axial–symmetrical deformed target nucleus and in particular to find the Coulomb barrier, by using the double folding model (DFM). The program calculates the nucleus–nucleus potential as a function of the distance between the centers of mass of colliding nuclei as well as of the angle between the axis of symmetry of the target nucleus and the beam direction. The most important output parameters are the Coulomb barrier energy and the radius. Since many researchers use a Woods–Saxon profile for the nuclear term of the potential we provide an option in our code for fitting the DFM potential by such a profile near the barrier. Program summaryProgram title: DFMDEFCatalogue identifier: AENI_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENI_v1_0.htmlProgram obtainable from: CPC Program Library, Queen’s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 2245No. of bytes in distributed program, including test data, etc.: 215442Distribution format: tar.gzProgramming language: C.Computer: PC, Mac.Operating system: Windows XP (with the GCC-compiler version 2), MacOS, Linux.RAM: 100 MB with average parameters setClassification: 17.9.Nature of problem:The code calculates in a semimicroscopic way the bare interaction potential between a spherical projectile nucleus and a deformed but axially symmetric target nucleus as a function of the center of mass distance as well as of the angle between the axis of symmetry of the target nucleus and the beam direction. The height and the position of the Coulomb barrier are found. The calculated potential is approximated by a conventional Woods–Saxon profile near the barrier. Dependence of the barrier parameters upon the characteristics of the effective NN forces (like, e.g., the range of the exchange part of the nuclear term) can be investigated.Solution method:The nucleus–nucleus potential is calculated using the double folding model with the Coulomb and the effective M3Y NN interactions. For the direct parts of the Coulomb and the nuclear terms, the Fourier transform method is used. In order to calculate the exchange parts the density matrix expansion method is applied.Running time:Using a PC with 1.60 GHz processor under Windows XP less than 1 min in the case of reduced calculations and about 40 min in the case of full calculations for one value of angle. Using Apple computer under MacOS the code runs faster by a factor of 5.