LINDEN: code for level density calculations of deformed nuclei using Lipkin-Nogami projectors in the BCS approach. O. Rodriguez, F. Garcia, H. Dias, J. Mesa, J.D.T. Arruda-Neto, E. Garrote, F. Guzman.

PROGRAM SUMMARY
Title of program: LINDEN
Catalogue identifier: ADOC
Ref. in CPC: 137(2001)405
Distribution format: tar gzip file
Operating system: MS-DOS 6.00, Windows 95 and Windows NT 4.0
High speed store required: 105MK words
Number of bits in a word: 16
Number of lines in distributed program, including test data, etc: 4139
Keywords: BCS model, Lipkin-Nogami model, Level density, State density, Spin distribution calculation, Spin cutoff parameters, Nuclear physics, Spectra, Level scheme.
Programming language used: Fortran
Computer: Micro Intel 80486+80487 , Pentium Intel II ,

Other versions of this program:

 Cat. Id.  Title                             Ref. in CPC
 ADAI      DENCOM                             86(1995)129                    
 

Nature of problem:
The level density for nuclear reaction cross section calculations, using a combined method [1] with the Lipkin-Nogami approximation [2], is obtained. The level density is computed at high excitation energy by using a quantum-statistical model [3]. At low excitation energy the level density is calculated from quasiparticle spectra obtained with the Lipkin-Nogami model. This program is a new version of DENCOM [1].

Method of solution:
The energy range to compute level density is divided into two intervals; first, from zero to some value of the excitation energy, where the level density is calculated using a combinatorial method; and second, from the matching energy to the final excitation energy, where a quantum-statistical method is used to compute the level density.

Restrictions:
Maximum number of quasiparticles to take into account for the quasiparticle spectrum calculation: three for an odd system and four for an even system.

Typical running time:
It depends on the choice of the calculation. To compute only the quasiparticle spectrum, the running time is approximately 43 seconds, and to calculate the statistical level density, the running time is approximately 7 seconds. For the test, when both choices are computed, the running time is 50 seconds.

References:

 [1] F. Garcia, O. Rodriguez, V.A. Rubchenya, E. Garrote, Comp. Phys.    
     Commun. 86 (1995) 129.                                              
 [2] P. Moller, J.R. Nix, Nucl. Phys. A536 (1992) 20.                    
 [3] P. Decowski, W. Grochulski, A. Marcinkowski, K. Siwek and           
     Z. Wilhelmi, Nucl. Phys. A110 (1968) 129.