V. Paar (Univ. Zagreb) - Low-lying levels of /sup 77/Se studied by thermal neutron capture and evidence for a new term in the E2 operator of TQM (IBM).

 

Accession Number
002487566
Author
Tokunaga Y. Seyfarth H. Meyer RA. Schult OWB. Borner HG. Barreau G. Faust HR. Schreckenbach K. Brant S. Paar V. Vouk M. Vretenar D.
Institution
Inst. fur Kernphys., KFA Julich, West Germany.
Title
Low-lying levels of /sup 77/Se studied by thermal neutron capture and evidence for a new term in the E2 operator of TQM (IBM).
Source
Nuclear Physics A, vol.A439, no.3, 17 June 1985, pp.427-55. Netherlands.
Country of Publication
Netherlands.
Abstract
A high-resolution study of the /sup 76/Se(n, gamma ) reaction was carried out with curved-crystal and pair spectrometers and conversion electrons were measured following slow-neutron capture. The resulting data yield very precise level energies and spin and parity assignments for most of the levels. The neutron separation energy of /sup 77/Se was measured as 7418.85+or-0.07 keV. The experimental data were compared with theoretical results for the level energies in /sup 77/Se and the E2, M1 and E1 branching ratios obtained from the SU(6) particle-vibration model (PTQM). The authors used /sup 76/Se as a slightly perturbed SU(5) vibrational core and the particle-vibration interaction strengths from the PTQM calculation for /sup 75/Se. In this frame there is evidence for a triangle n=2 term in the E2 operator. This term has not been included so far in TQM and IBM calculations. (44 References).
Abstract Number
A85083889
Subject Headings
Neutron radiative capture. Nuclear collective model. Nuclear energy level transitions. Nuclear spin and parity. Nuclei with mass number 59 to 89. SU / sub n .
Key Phrase Identifiers
E1; level energies; level spins; level parities; SU(6) model; thermal neutron capture; E2 operator; /sup 76/Se(n, gamma ); M1; branching ratios; SU(5) vibrational core; particle-vibration interaction; PTQM calculation; IBM calculations.
Classification Codes
Nuclear spin, parity, and isobaric spin [A2110H]; Nuclear level density and structure [A2110M]; Nuclear collective models [A2160E]; Nuclear models based on group theory [A2160F]; Lifetimes and transition probabilities of nuclei [A2320C]; Nuclear gamma transitions and level energies [A2320L]; Properties of nuclei with 59
Treatment
Theoretical or mathematical. Experimental.
CODEN
NUPABL
Language
English.
ISSN
0375-9474.
Publication Type
Journal Paper.
Update Code
198500.