Decay of the very neutron-deficient isotope $^{131}$Pm

Z.G. Gan; Z. Qin; J.S. Guo; L.J. Shi; H.Y. Liu; T.R. Guo; X.G. Lei; R.C. Ma; W.X. Huang; S.G. Yuan; X.Q. Zhang; G.M. Jin

doi:doi:10.1007/s100500050317

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2023 Impact factor 2.6

Hadrons and Nuclei

Eur. Phys. J. A 6, 59-61

Decay of the very neutron-deficient isotope ¹³¹Pm

Z.G. Gan - Z. Qin - J.S. Guo - L.J. Shi - H.Y. Liu - T.R. Guo - X.G. Lei - R.C. Ma - W.X. Huang - S.G. Yuan - X.Q. Zhang - G.M. Jin

Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, P.R. China

Received: 11 January 1999 / Revised version: 20 May 1999 Communicated by J. Äystö

Abstract
The decay of ¹³¹Pm has been investigated by means of $\gamma$ -ray spectroscopy. The ¹³¹Pm nuclei were produced by fusion-evaporation reaction of ¹⁰⁶Cd(³²S,3p4n) at the beam energy of 170 MeV. A helium-jet technique and a tape transport system were used to collect the activities and transfer them to a detecting position for X and $\gamma$ rays measurement. Two $\gamma$ rays of 185.0 and 220.0 keV were unambiguously identified to follow the $\beta ^{+}$ decay of ¹³¹Pm by results of X- $\gamma$ and $\gamma$ - $\gamma$ coincidence. A growth-decay feature of the decay curve for 87.8 keV $\gamma$ -ray of ¹³¹Nd confirmed the production of ¹³¹Pm nuclei. The half-life of ¹³¹Pm was measured to be 6.3 $\pm$ 0.8 s. A partial decay scheme of ¹³¹Pm is proposed on the basis of X- $\gamma$ and $\gamma$ - $\gamma$ coincidence data in this experiment and the known structure information deduced from in-beam experiments of the daughter nucleus ¹³¹Nd.