Semiclassical description of alpha clustering in heavy nuclei

Journal Article · Fri Nov 01 00:00:00 EST 1991 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.44.1929· OSTI ID:5099182

Raduta, A A; Delion, D S; Ursu, I I ^[1]; Lo Iudice, N ^[2]

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1. Institute of Atomic Physics, Bucharest, P.O. Box MG-6 (Romania)
2. Dipartimento di Scienze Fisiche (Universita di Napoli Federico II'') Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Napoli (Italy)

A semiclassical model for {alpha} clustering in heavy nuclei is developed where the nucleus is viewed as a composite system of pairwise correlated nucleons interacting with {alpha} particles. The nucleons are treated microscopically by the use of a spherical shell-model basis while the {alpha} particles are considered as elementary bosons carrying angular momentum zero and one. The description of such a system is based on a time-dependent variational formalism, which yields BCS-like equations for the ground and some low-lying excited states. It is shown that the system may undergo transitions from a nucleon superfluid phase to intermediate phases characterized by the coexistence of few {alpha} clusters with a nucleon pair condensate. The model allows also to study in a random-phase-approximation context the fluctuations of the system around the BCS-like configurations. Two peculiar aspects emerge, the occurrence of collective states describing a wobbling motion of the {alpha} particles and the unusually large number of collective states describing a coherent motion of nucleons oscillating in phase with {alpha} particles. The numerical illustrative applications refer to {sup 220}Ra.

• OSTI ID: 5099182
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Vol. 44:5; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
HEAVY NUCLEI
CLUSTER MODEL
RADIUM 220
NUCLEAR STRUCTURE
ALPHA PARTICLES
BCS THEORY
SEMICLASSICAL APPROXIMATION
VARIATIONAL METHODS
ALKALINE EARTH ISOTOPES
ALPHA DECAY RADIOISOTOPES
CHARGED PARTICLES
EVEN-EVEN NUCLEI
ISOTOPES
MATHEMATICAL MODELS
MILLISEC LIVING RADIOISOTOPES
NUCLEAR MODELS
NUCLEI
RADIOISOTOPES
RADIUM ISOTOPES
SECONDS LIVING RADIOISOTOPES
653001* - Nuclear Theory- Nuclear Structure
Moments
Spin
& Models