New heavy neutron-rich isotope 238Th

New heavy neutron-rich isotope ²³⁸Th

XU Yanbing，

YUAN Shuanggui，

YANG Weifan，

LI Zongwei，

MA Taotao，

XIONG Bing，

HE Jianjun

Nuclear Science and Techniques

Vol.10, No.2

pp.65-68

Published in print 01 Mar 1999

26400

A new nuclide ²³⁸Th has been produced via multinucleon transfer reaction by 60 MeV/u ¹⁸O ion irradiation of the natural uranium. The thorium was radiochemically separated from the mixture of uranium and reaction products. The activity of thorium was measured by using an HPGe detector and a planar HPGe detector. The ²³⁸Th has been identified for the first time by measuring the growth and decay of the γ-rays from its daughter ²³⁸Pa. The half-life of ²³⁸Th was determined to be 9.4±2.0 min. In addition, a new γ-ray of 89.0±0.3keV with T_1/2=8.9±1.5min was found in the γ spectrum gated with X-rays of Pa and assigned to ²³⁸Th β^- decay based on measurements of transition energy and half life.

Multinucleon transfer reactionChemical separationNew nuclideSynthesis and identification

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