Influence of neutron-core excitations on high-spin states in $^{88}$Sr


Influence of neutron-core excitations on high-spin states in $^{88}$Sr

Stefanova, E.; Schwengner, R.; Reif, J.; Schnare, H.; D\Önau, F.; Wilhelm, M.; Fitzler, A.; Kasemann, S.; von Brentano, P.

High-spin states of the nucleus $^{88}$Sr have been studied via the
reaction $^{80}$Se($^{11}$B,$p$2$n$) at a beam energy of 45 MeV. Gamma-rays
were detected with the six-detector array OSIRIS CUBE. The level scheme of
$^{88}$Sr has been extended up to $E \approx$ 11 MeV and $J = 17$.
Mean lifetimes of three levels have been determined using the
Doppler-shift-attenuation method. The level structures in $^{88}$Sr have
been interpreted in terms of the shell model. The calculations were performed
in the configuration space $(0f_{5/2}, 1p_{3/2}, 1p_{1/2}, 0g_{9/2})$ for
the protons and $(1p_{1/2}, 0g_{9/2}, 1d_{5/2})$ for the neutrons. These
calculations describe the high-spin level sequences linked by $M1$ transitions
with strengths of $B(M1) \leq 1.4$ W.u. as multiplets of seniority
$\upsilon$ = 4 and 6 states including proton configurations and neutron-core
excitations.

Keywords: Nuclear Structure; In-beam spectroscopy; Cologne OSIRIS cube; Shell-model calculations

  • Physical Review C, Vol. 62, 054314, 1-10

Permalink: https://www.hzdr.de/publications/Publ-3422
Publ.-Id: 3422