3. DESCRIPTION OF PROBLEM OR FUNCTION
ECIS-79 uses a sequential iteration method for solving the coupled differential equations arising in nuclear model calculations. It also performs parameter searches to fit calculated results to experimental data. It can be used for a range of models, e.g. first or second order harmonic or anharmonic vibrational model, symmetric or asymmetric rotational model, with a similar range of interaction potentials. It includes spin-orbit deformation.
ECIS-95 is a generalization of ECIS-79: for the rotational model vibrational bands are included. An option for solving the Dirac equation has been added. It also contains the statistical model including width fluctuation corrections as formulated by Peter Moldauer. Besides the use of Bessel expansion for form factors, the use of deformation lengths and the use of 'symmetrized' Woods-Saxon potentials, it includes:
- two bound state transitions for particle-mode excitations with the possibility of the particle in the continuum
- expression of cross sections in terms of Legendre polynomials
- possibility of angular distribution for uncoupled states without
giving explicitly all the reduced nuclear matrix elements
- for Coulomb excitation, use of the magnetic multipole.
New version differs from previous version in the following features:
- The whole program was converted to double-precision
- In ECIS03 the dispersion relation as described by "C. MAHAUX AND R. SARTOR IN NUCL. PHYS A528 (1991) 253", is added to the real potencial, (it is a generalisation of the dispersion relation as described in "MAHAUX, C. and SARTOR, R., Nucl. Phys. A458 (1986) 25" already introduced in ECIS96 and 97).
- Conversion of all FORMATS from Hollerith notation into 'quotes' notation.
- ECIS06 is primarily ECIS03 modified for the use of a different relativistic 'reduced mass' in front of 'scalar' potentials, differing from the one used in front of Coulomb potentials. It is the application to coupled equations of the principles described in 'DWBA05' announced in the Workshop 'Perspectives on Nuclear Data in the Next Decade', on the 26-28/9/2005 at Bruyeres-le-Chatel, France.
- Some generalisations have been introduced, in particular for the dispersion relation.
This new version, NEA-0850/18, contains the following features:
- The LOG tables description has been updated
- The re-start of a search parameter calculation by a different job was not possible. This new version fixes this problem.
- Automatic self-protecting features have been updated: in uninteresting situations, stop for low energy and external potential have been suppressed.