EPJ

2023 Impact factor 2.6
EPJ A - Hadrons and Nuclei
Hadrons and Nuclei
Eur. Phys. J. A 15, 185-188 (2002)
DOI: 10.1140/epja/i2001-10251-7

Decay studies of $\mth{N\approx Z}$ nuclei from $\chem{^{75}Sr}$ to $\chem{^{102}Sn}$

T. Faestermann1, R. Schneider1, A. Stolz1, K. Sümmerer2, E. Wefers1, J. Friese1, H. Geissel2, M. Hellström2, 3, P. Kienle1, H.-J. Körner1, M. Mineva3, M. Münch1, G. Münzenberg2, C. Schlegel2, K. Schmidt2, P. Thirolf4, H. Weick2 and K. Zeitelhack1

1  Technische Universität München, 85748 Garching, Germany
2  Gesellschaft für Schwerionenforschung mbH, 64291 Darmstadt, Germany
3  Lund University, 22100 Lund, Sweden
4  Ludwig-Maximilians-Universität München, 85748 Garching, Germany

thomas.faestermann@ph.tum.de

(Received 21 March 2002 / Published online: 31 October 2002)

Abstract
Neutron deficient nuclei near $\chem{^{100}Sn}$ have been produced by fragmentation of a $1\cdot \ab{A}$ GeV $\chem{^{112}Sn}$ beam. The fragments were separated, identified and stopped in a highly segmented silicon strip detector stack. This detector measured the total energy of emitted $\beta^+$-particles. $\gamma$-radiation was measured with surrounding detectors. The half-lives for many nuclides have been determined for the first time and give important information for the following topics: For the heaviest particle-stable odd-odd nuclei $\chem{^{90}Rh}$, $\chem{^{94}Ag}$ and $\chem{^{98}In}$ we observed for the first time fast $\beta$-decays, compatible with superallowed Fermi transitions and confirmed such decays for $\chem{^{78}Y}$, $\chem{^{82}Nb}$ and $\chem{^{86}Tc}$. We have also observed long-lived T=0 states in some of these nuclei. We measured the half-lives of all rp-process waiting-point nuclei from $\chem{^{80}Zr}$ up to $\chem{^{92,93}Pd}$. In addition we find the proton drip line nucleus $\chem{^{77}Y}$ to decay dominantly via $\beta$-decay. To study the Gamov-Teller strength in the $\beta$-decay near the doubly magic $\chem{^{100}Sn}$ we measured the half-life, $\beta$- and $\gamma$-spectrum of $\chem{^{102}Sn}$. We propose a level scheme for the daughter nuclide $\chem{^{102}In}$ and deduce the Gamov-Teller strength $(B_\ab{GT} = 4.0 \pm 0.6)$. This is one of the largest values known.

PACS
21.10.Tg - Lifetimes.
23.40.Hc - Relation with nuclear matrix elements and nuclear structure.
23.50.+z - Decay by proton emission.

© Società Italiana di Fisica, Springer-Verlag 2002

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