JAERI.readme Optical model potential parameters collected in JAERI (Provided by T. Fukahori, 15 Sept 1997, original file name jaeri_omp.dat) *************************************************************************
Contact person -------------- Tokio Fukahori (JAERI, Tokai-mura, Japan) e-mail: fukahori@cracker.tokai.jaeri.go.jp
Contents -------- Optical model potential parameters are stored in jaeri.dat as those of global, regional and individual nuclei. The parameter sets for neutron, proton, triton, He-3 and alpha include individual 87, 7, 1, 1 and 6 sets, respectively. The parameters for individual nuclei cover the atomic number range from 33 to 100.
Format Description ------------------ Optical model parameters are stored between the OMP record and an ENDOMP record:
OMP ... ENDOMP
An INCIDENT section has to be used to specify the incident particle. Between an INCIDENT record and an ENDINC record, the optical model parameters of the corresponding incident particle are stored:
INCIDENT n ... ENDINC
where 'n' represents the incident particle in the same rule as nuclide name:
10 neutron 10010 proton 10020 deuteron 10030 triton 20040 alpha
The following auxiliary records are defined:
TARGET n1, n2
where 'n1' and 'n2' indicate a range of nuclei for which the optical potential parameters can be applied.
TYPE n
'n' defines type of form factors of imaginary parts:
n Surface term Volume term 1 Gaussian form none 2 derivative Wood-Saxon form none 3 none Wood-Saxon form 4 Gaussian form Wood-Saxon form 5 derivative Wood-Saxon form Wood-Saxon form
COULOMB n
Coulomb radius parameter (fm) for charged particles. In the DATA section, parameters are stored under the following parameter names:
V real potential depth (MeV) WV volume type imaginary potential depth (MeV) WS surface type imaginary potential depth (MeV) VSO real part of spin-orbit potential depth (MeV) WSO imaginary part of spin-orbit potential depth (MeV) EMIN lower boundary of incident particle energy (MeV) EMAX higher boundary of incident particle energy (MeV)
By some researchers, very complicated formula have been proposed. For each type, however, only the following energy dependent potential can be stored. Diffuseness parameters have almost the same form as nuclear radii. DATA-line symbols in the columns from 1 to 9 of the DATA section represent the terms of above expressions as follows:
E0 constant term. E1 first order term of energy. E2 second order term of energy. E5 square root term. E9 Z/A**(1/3) term. SYM symmetric term. R nuclear radius parameter. RC constant term of nuclear radius. A diffuseness parameter.
Energy dependent terms and symmetric terms of R and A can be represented as:
R-E1 (=r1), R-SYM (=rs), A-E1 (=a1), A-SYM (=as).
Example: OMP INCIDENT 10; neutron TARGET 130000, 239999 TYPE 1 DATA V, WS, VSO, EMIN, EMAX E0 48.46, 4.94, 6.0, 0.0, 11.0 E0 51.87, 7.14 6.0, 11.0, 20.0 E1 0.0, 0.20, 0.0, 0.0, 11.0 E1 -0.31, 0.0, 0.0, 11.0, 20.0 R 1.18, 1.26, 1.01, 0.0, 20.0 A 0.64, 0.58, 0.5, 0.0, 20.0 ENDDATA ENDINC ENDOMP
This example stores the following potential parameters:
V = 48.46 for En<11 MeV, and = 51.87 - 0.31*En for En>11 MeV, WS = 4.94 + 0.2*En for En<11 MeV, and = 7.14 for En>11 MeV, VSO = 6.0 MeV R (real term) = 1.18*A1/3 fm, R (surface term) = 1.26*A1/3 fm, R (volume term) = 1.01*A1/3 fm, Diffuseness parameter of the real term = 0.64 fm, Diffuseness parameter of the surface term = 0.58 fm, Diffuseness parameter of the volume term = 0.50 fm.