Investigation of particle-core coupling in 69Ge

• Published in: Nuclear physics. A Vol. 626; no. 3; pp. 799 - 856
• Main Authors: Becker, F., Eberth, J., Burkardt, T., Freund, S., Hermkens, U., Kabadiyski, M.K., Mylaeus, T., Skoda, S., Teichert, W., Thomas, H.G., von der Werth, A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-11-1997
• Subjects: measured Eγ, Iγ, γγ-coin, γ( Ep; θ); NUCLEAR REACTIONS 66Zn(α,n), E = 13-23 MeV, 60Ni( 12C,2np), E = 48, 56 MeV; recoil distance Doppler shifts. 69Ge deduced high-spin levels, J, δ, π, [formula omitted], τ, B(E). Enriched targets, Ge-detectors. Particle-core coupling; shell-model calculations; NUCLEAR REACTIONS 66Zn(α,n), E = 13-23 MeV, 60Ni( 12C,2np), E = 48, 56 MeV; 21.10.−k; 27.50.+e; measured E γ , I γ , γγ-coin, γ( E p ; θ); 23.20.−g; recoil distance Doppler shifts. 69Ge deduced high-spin levels, J, δ, π, τ 1 2 , τ, B(E). Enriched targets, Ge-detectors. Particle-core coupling; 21.60.−n; shell-model calculations
• ISSN: 0375-9474
• DOI: 10.1016/S0375-9474(97)00510-1

The nucleus
69Ge has been studied in the reactions
66Zn(α,n)
69Ge and
60Ni(
12C,2pn)
69Ge. Using γ-spectroscopic methods energies, intensities, excitation functions, γγ-coincidences, angular distributions, and the linear polarization of γ-rays as well as lifetimes were measured. From the α-induced reaction, states up to spin
J =
21
2
and
E
x = 4267 keV have been established in
69Ge including 178 new transitions and 62 new levels. Spin and parity were determined for 79 levels. High-spin states populated via the reaction
12C +
60Ni
show 61 new transitions and 27 new levels up to spin
J =
37
2
and
E
x = 9182 keV. For 19 levels ps-lifetimes were determined. Eight complete multiplets originating from the coupling of the odd neutron to the core
68Ge have been identified and candidates for further multiplets are proposed. Significant deviations from the simple De-Shalit core-coupling model were found. Shell-model calculations, which were performed for
68Ge and
69Ge with the code RITSSCHIL on a parallel computer in a large configuration space, show that proton excitations from the
2
p
3
2
to higher shells play an important role for the detailed structure of the particle-core multiplets.