A Global Elastic Nucleon-Nucleus Optical Potential

By:
S. Weppner

Applet by: G. Diffendale and G. Vittorini

Phys. Rev. C 80, 034608 (2009)

correction in red to equation 1. of the paper below. Also a wrong sign in one of the numbers in the chart, also in red.

This is a Non Relativistic Distorted Wave Born Approximation

with a Relativistic Correction↑ using a modified Numerov Routine

Please make
suggestions by emailing S. Weppner

If the Calculate button is depressed then the program is working, it may take a few moments.

The
applet will error unless the energy ranges are between 30 and 160

WP stands for Weppner-Penney, KD stands for Koning-Delaroche and is Ref. [5]. MD stands for Madland and is Ref. [4] The figures below were generated with the help of TALYS. Some TALYS input files for the WP and MD potentials are located here. This directory has source code (*.rb) to generate more files, potential files (*.pot), and example TALYS input files for Ca40.

(0.1)CORRECTION TO PAPER IN RED |

Our complex phenemological optical model potential contains the traditional
volume (
), surface (
), and spin-orbit (
) nuclear terms which are
delineated using the
standard Woods-Saxon form factors

(0.1) |

where is the radius parameter and is the diffusive parameter. The is a placeholder for the , , or designation. The phenemological optical model potential takes a standard form

(0.2) |

where the and are the real and imaginary potential amplitudes respectively and is the coulomb term which has the following traditional format with a proton projectile:

(0.3) |

For a neutron projectile it is set to zero. For this potential takes on a functional form and is detailed below. The amplitudes, radii, and diffusive parameters have the following dependent variables:

- +1 if projectile is a proton, -1 if a neutron

- set to 2 if the target is tradittionally doubly magic

- otherwise set to 0.

Explicity the amplitudes are given in the following polynomial formats:

The volume amplitudes:

The surface amplitudes:

The spin orbit amplitudes:

The volume radius and diffusive parameters:

The surface radius and diffusive parameters:

the spin-orbit radius and diffusive parameters:

and finaly the the coulumb radius parameter:

These parameters are listed in table 1.

↑ A. Nadasen et al. "Elastic Scattering of 80-180 MeV Protons and the Proton-Nucleus Optical Potential."

Physical Review C 23 (1981): 1023-1043.

If you have any questions or problems please contact S. Weppner

Stephen Weppner 2009-06-24