skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Nonlocality and off-shell effects in nuclear optical potentials at medium energies

Abstract

The microscopic optical potential is calculated by starting with the G-matrix for infinite nuclear matter within the framework of the Brueckner theory as modified by Brieva and Rook. Using these nuclear matter results, the optical potential for finite nuclei is developed by taking into account the off-shell effects and the nonforward parts of the amplitudes. These effects give rise to an energy dependent and nonlocal optical potential in configuration space. The equivalent local potential is a sum of terms, the first being the familiar zero range expression which is often used in many practical calculations. The remaining terms of the optical potential contain nonlocality and finite-range effects which arise because of the finite extent of the nucleus. The calculations show that off-shell and nonforward corrections modify the potential in the surface region, hence changing its shape from that of the density distribution. A nonlocal phenomenological potential is also developed which is energy independent and whose local equivalent potential yields an energy dependence seen in phenomenological potentials. Using the nonlocal potential, the elastic scattering cross sections and the wave functions for the P-/sup 40/Ca system at 400, 550, and 700 MeV energies are calculated. Local equivalent potentials are then obtained usingmore » cross sections as data in an optical model search code. The calculations show that the amplitude of the nonlocal wave function in the nuclear interior is much smaller than those of local wave functions. This so-called Perey effect is investigated and is shown to have an important role in nuclear reactions with large momentum transfers.« less

Authors:
Publication Date:
Research Org.:
Colorado Univ., Boulder (USA)
OSTI Identifier:
6244051
Resource Type:
Thesis/Dissertation
Resource Relation:
Other Information: Thesis (Ph. D.)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; NUCLEAR MATTER; NUCLEAR POTENTIAL; BRUECKNER MODEL; CALCIUM 40; CROSS SECTIONS; ENERGY DEPENDENCE; FINITE-RANGE INTERACTIONS; LOCALITY; MEV RANGE 100-1000; NONLOCAL POTENTIAL; WAVE FUNCTIONS; ALKALINE EARTH ISOTOPES; CALCIUM ISOTOPES; ENERGY RANGE; EVEN-EVEN NUCLEI; FUNCTIONS; INTERACTIONS; ISOTOPES; LIGHT NUCLEI; MATHEMATICAL MODELS; MATTER; MEV RANGE; NUCLEAR MODELS; NUCLEI; POTENTIALS; STABLE ISOTOPES; 653000* - Nuclear Theory

Citation Formats

Haghbin, H. Nonlocality and off-shell effects in nuclear optical potentials at medium energies. United States: N. p., 1982. Web.
Haghbin, H. Nonlocality and off-shell effects in nuclear optical potentials at medium energies. United States.
Haghbin, H. 1982. "Nonlocality and off-shell effects in nuclear optical potentials at medium energies". United States.
@article{osti_6244051,
title = {Nonlocality and off-shell effects in nuclear optical potentials at medium energies},
author = {Haghbin, H},
abstractNote = {The microscopic optical potential is calculated by starting with the G-matrix for infinite nuclear matter within the framework of the Brueckner theory as modified by Brieva and Rook. Using these nuclear matter results, the optical potential for finite nuclei is developed by taking into account the off-shell effects and the nonforward parts of the amplitudes. These effects give rise to an energy dependent and nonlocal optical potential in configuration space. The equivalent local potential is a sum of terms, the first being the familiar zero range expression which is often used in many practical calculations. The remaining terms of the optical potential contain nonlocality and finite-range effects which arise because of the finite extent of the nucleus. The calculations show that off-shell and nonforward corrections modify the potential in the surface region, hence changing its shape from that of the density distribution. A nonlocal phenomenological potential is also developed which is energy independent and whose local equivalent potential yields an energy dependence seen in phenomenological potentials. Using the nonlocal potential, the elastic scattering cross sections and the wave functions for the P-/sup 40/Ca system at 400, 550, and 700 MeV energies are calculated. Local equivalent potentials are then obtained using cross sections as data in an optical model search code. The calculations show that the amplitude of the nonlocal wave function in the nuclear interior is much smaller than those of local wave functions. This so-called Perey effect is investigated and is shown to have an important role in nuclear reactions with large momentum transfers.},
doi = {},
url = {https://www.osti.gov/biblio/6244051}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1982},
month = {Fri Jan 01 00:00:00 EST 1982}
}

Thesis/Dissertation:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this thesis or dissertation.

Save / Share: