Potential energy surfaces in the two-center shell model

doi:10.1016/0375-9474(72)90855-X

Nuclear Physics A

Volume 190, Issue 3, 14 August 1972, Pages 533-547

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Abstract

The two-center shell model of two equal overlapping spheroids is combined with Lawrence's liquid-drop shapes. Within this framework, potential energy surfaces for nuclei from different mass regions are calculated. In particular, the transition of the ground state deformation from spherical to deformed is investigated for a sequence of ruthenium isotopes.

References (31)

S.G. Nilsson et al.
Nucl. Phys.
(1969)
P. Holzer et al.
Nucl. Phys.
(1969)
D. Scharnweber et al.
Nucl. Phys.
(1971)
U. Mosel et al.
Phys. Rev.
(1971)
U. Mosel et al.
Nucl. Phys.
(1971)
M. Bolsterli et al.
LA-DC-12817
(1971)
Phys. Rev. C,...H.C. Pauli et al.
Nucl. Phys.
(1971)
J.R. Nix et al.
Nucl. Phys.
(1965)
J.N.P. Lawrence
Phys. Rev.
(1965)
J.N.P. Lawrence
Los Alamos report LA-3774
(1967)
R.W. Hasse
Ann. of Phys.
(1971)
B. Slavov and A. Faessler, private...
K. Albrecht

M. Abramowitz et al.

P. Quentin et al.

Nucl. Phys.

(1970)

C. F. Tsang, thesis,...

B.L. Andersen

Nucl. Phys.

(1971)

R.F. Casten et al.

Phys. Lett.

(1970)

Cited by (11)

Nuclear Data Sheets for A = 98
1983, Nuclear Data Sheets
Study of 103Tc and the onset of deformation around N = 60
1983, Nuclear Physics, Section A
The ¹⁰⁴Ru(d, ³He)¹⁰³Tc reaction has been investigated at E_d = 50 MeV. Transitions to 22 states in ¹⁰³Tc were studied. The measured angular distributions were compared with DWBA calculations, from which l-transfers and spectroscopic factors were deduced. To investigate the possible onset of quadrupole deformation around N = 60, the potential energy curves for the oddmass ^97–103Tc isotopes was calculated. Excited states were studied with the IBFA model.
Triaxiality and its dynamics in 104Ru investigated by multiple Coulomb excitation
1982, Nuclear Physics, Section A
The electromagnetic properties of ¹⁰⁴Ru have been investigated by multiple Coulomb excitation. Thin and thick targets of ¹⁰⁴Ru have been bombarded with 4.6 MeV/u ²⁰⁸Pb. From the measurement of particle-particle-γ coincidences and the γ-multiplicity (thin target) and γγ coincidences (thick target) the level scheme of ¹⁰⁴Ru could be extended appreciably. Numerous B(E2) values for the ground-state band and excited bands as well as static quadrupole moments for the ground-state band up to I^π = 8⁺ could be determined by comparing experimental Coulomb excitation yields (thin target) to semiclassical calculations. The results are discussed in the framework of different collective models as the generalized collective model, the interacting boson model and the asymmetric rotor model considering especially the aspects of triaxial deformation and γ-softness. The electromagnetic moments show the first excited 0⁺ state not to be the predicted collective excitation but to belong to an intruder configuration.
The decay of 79.8 sec 109Rh into levels of 109Pd
1978, Journal of Inorganic and Nuclear Chemistry
The β⁻-decay of 79.8 sec ¹⁰⁹Rh into levels of ¹⁰⁹Pd has been investigated by γ-ray spectroscopy and γ-γ-coincidence measurements. The activities have been produced by thermal-neutron induced fission of ²³⁹Pu and subsequent chemical separation of the rhodium fraction from the fission product mixture. A total of 31 γ-rays have been assigned to the decay of ¹⁰⁹Rh, and a level scheme of ¹⁰⁹Pd is proposed and briefly discussed within the framework of different nuclear models. From beta branching ratios a groundstate spin and parity of $52^{+}$ can be deduced for ¹⁰⁹Rh.
Identification of short-lived ruthenium and rhodium isotopes in fission by rapid chemical separations
1978, Journal of Inorganic and Nuclear Chemistry
Short-lived ruthenium and rhodium isotopes were produced via thermal neutron induced fission of ²³⁵U, ²³⁹Pu and ²⁴⁹Cf and via fast neutron induced fission of ²³⁸U. The ruthenium isotopes and their descendants were isolated from the fission product mixtures by means of a rapid chemical separation procedure. Typically 7.6 sec were required from the end of irradiation to the start of counting. The γ-ray singles spectra as well as the γ-γ-coincidences were recorded with Ge(Li)-detectors. New short-lived nuclides were identified on the basis of their decay characteristics, and existing data of the longer lived isotopes were confirmed. Results are presented for the ruthenium isotopes 3.75 min ¹⁰⁷Ru, 4.55 min ¹⁰⁸Ru, 34.5 sec ¹⁰⁹Ru, 12.9 sec ¹⁰⁹Ru (isomer), 12.6 sec ¹¹⁰Ru, 3 sec ¹¹¹Ru, 3.6 sec ¹¹²Ru, 3 sec ¹¹³Ru, and the rhodium isotopes 17 sec ¹⁰⁸Rh, 79.8 sec ¹⁰⁹Rh, 3.3 sec ¹¹⁰Rh, 11 sec ¹¹¹Rh.
A new two-center shell model for nuclear fission
1973, Nuclear Physics, Section A
A two-center single-particle potential is proposed which has the Lawrence family of liquid-drop shapes as its equipotentials. An improved parameterization of these shapes is given that facilitates their use. Only two deformation parameters are required to describe all relevant nuclear shapes for symmetric fission. These encompass Nilsson ground state shapes with ϵ and (approximately) ϵ₄ deformations, dumbbells and spheroidal fragments at large separation. The corresponding potential evolves from a deformed harmonic oscillator for the ground state of the fissioning nucleus to two deformed harmonic oscillators for well-separated fragments. In the single-particle calculation, a Thomas-type spin-orbit potential is used together with an l² correction term. The nuclear deformation energy is calculated by Strutinsky's prescription, including pairing energy. Results are given as deformation energy maps for the symmetric fission mode of various actinide nuclei. The asymmetric generalization of the model is outlined.

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^†: Present address: Abt. für Kernphysik, Max-Planck-Institut für Chemie, Mainz, Germany.

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Nuclear Physics A

Abstract

References (31)

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Rev.

Nucl. Phys.

LA-DC-12817

Nucl. Phys.

Nucl. Phys.

Phys. Rev.

Los Alamos report LA-3774

Ann. of Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Cited by (11)

Nuclear Data Sheets for A = 98

Study of <sup>103</sup>Tc and the onset of deformation around N = 60

Triaxiality and its dynamics in <sup>104</sup>Ru investigated by multiple Coulomb excitation

The decay of 79.8 sec <sup>109</sup>Rh into levels of <sup>109</sup>Pd

Identification of short-lived ruthenium and rhodium isotopes in fission by rapid chemical separations

A new two-center shell model for nuclear fission