Effective interactions and coupling schemes in nuclei

doi:10.1016/0375-9474(94)90298-4

Nuclear Physics A

Volume 570, Issues 1–2, 28 March 1994, Pages 319-327

https://doi.org/10.1016/0375-9474(94)90298-4 Get rights and content

Abstract

Eigenstates of the shell model are obtained by diagonalization of the Hamiltonian submatrix defined by a given shell model subspace. Matrix elements of the effective nuclear interaction can be determined from experiment in a consistent way. This approach was introduced in 1956 with the ³⁸Cl-⁴⁰K spectra, has been applied in many cases and its latest success is in the s,d shell. This way, general features of the effective interaction have been determined. The T = 1 interaction is diagonal in the seniority scheme as clearly demonstrated in proton $1g_{92}^{n} and 1h_{112}^{n}$ configurations and in the description of semimagic nuclei by genrealized seniority. Apart from a strong and attractive pairing term, T = 1 interactions are repulsive on the average. The T = 0 interaction is attractive and is the origin of the central potential well in which nucleons are bound. It breaks seniority in a major way leading to deformed nuclei and rotational spectra. Such an interaction may be approximated by a quadrupole-quadrupole interaction which is the basis of the interacting boson model. Identical nucleons with pairing and quadrupole interactions cannot be models of actual nuclei. Symmetry properties of states with maximum T are very different from those of ground states of actual nuclei. The T = 1 interaction between identical nucleons cannot be approximated by pairing and quadrupole interactions. The rich variety of nuclear spectra is due to the competition between seniority conserving T = 1 interactions and the T = 0 quadrupole interaction between protons and neutrons.

References (13)

B.H. Wildenthal
Prog. Part. Nucl. Phys.
(1984)
B.A. Brown et al.
Ann. Rev. Nucl. Sci.
(1988)
G. Racah et al.
Physica
(1952)
G. Racah
S. Goldstein et al.
Phys. Rev.
(1956)
S.P. Pandya
Phys. Rev.
(1956)
I. Talmi
Rev. Mod. Phys.
(1962)

There are more references available in the full text version of this article.

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Effective interactions and coupling schemes in nuclei

Abstract

Prog. Part. Nucl. Phys.

Ann. Rev. Nucl. Sci.

Physica

Phys. Rev.

Phys. Rev.

Rev. Mod. Phys.