The 230Ra has been produced via multinucleon transfer and dissipative fragmentation of heavy target in the 60 MeV/u 18O ion reaction with natural thorium. The radium was radiochemically separated from irradiated thori...The 230Ra has been produced via multinucleon transfer and dissipative fragmentation of heavy target in the 60 MeV/u 18O ion reaction with natural thorium. The radium was radiochemically separated from irradiated thorium targets. 230Ac was obtained by 230Ra β-→230Ac. Thin Ra sources were prepared for observing fission fragments from β-delayed fission of 230Ac. The sources were exposed to the mica fission track detectors and measured by a HPGe γ detector. The two fission events were obtained and could been assigned to the β-delayed fission of 230Ac. The β-delayed fission probability of 230Ac was determined to be (1.19±0.85)×10-8.展开更多
MeV/u 18O ions were used to bombard natural uranium targets, and the heavy neutron-rich isotope 237Th was produced via multi-nucleon transfer reaction and dissipative fragmentation of the heavy target. A relatively fa...MeV/u 18O ions were used to bombard natural uranium targets, and the heavy neutron-rich isotope 237Th was produced via multi-nucleon transfer reaction and dissipative fragmentation of the heavy target. A relatively fast radiochemical procedure was used to separate thorium from the mixture of uranium and complex reaction products. The chemically separated thorium fractions were studied by the 7-ray spectroscopic method. The behaviors of the growth and decay of 853.7 and 865.0 keV-γrays of 237Pa decay were observed. The half-life of 237Th was determined to be 4.69±0.60 nun.展开更多
基金Supported by the National Natural Science Foundation of ChinaMajor State Basic Research Development Program, Chinese Aca
文摘The 230Ra has been produced via multinucleon transfer and dissipative fragmentation of heavy target in the 60 MeV/u 18O ion reaction with natural thorium. The radium was radiochemically separated from irradiated thorium targets. 230Ac was obtained by 230Ra β-→230Ac. Thin Ra sources were prepared for observing fission fragments from β-delayed fission of 230Ac. The sources were exposed to the mica fission track detectors and measured by a HPGe γ detector. The two fission events were obtained and could been assigned to the β-delayed fission of 230Ac. The β-delayed fission probability of 230Ac was determined to be (1.19±0.85)×10-8.
基金Supported by the National Natural Science Foundation of China (10075063), Major State Basic Research Development Program (G20000
文摘MeV/u 18O ions were used to bombard natural uranium targets, and the heavy neutron-rich isotope 237Th was produced via multi-nucleon transfer reaction and dissipative fragmentation of the heavy target. A relatively fast radiochemical procedure was used to separate thorium from the mixture of uranium and complex reaction products. The chemically separated thorium fractions were studied by the 7-ray spectroscopic method. The behaviors of the growth and decay of 853.7 and 865.0 keV-γrays of 237Pa decay were observed. The half-life of 237Th was determined to be 4.69±0.60 nun.
