50 research outputs found
β -delayed neutron emission from Ga 85
Decay of Ga85 was studied by means of β-neutron-γ spectroscopy. A pure beam of Ga85 was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and a high-resolution electromagnetic separator. The β-delayed neutron emission probability was measured for the first time, yielding 70(5)%. An upper limit of 0.1% for β-delayed two-neutron emission was also experimentally established for the first time. A detailed decay scheme including absolute γ-ray intensities was obtained. Results are compared with theoretical β-delayed emission models
Experimental study of the β decay of the very neutron-rich nucleus Ge 85
The β-decay properties of the very neutron-rich nucleus Ge85, produced in the proton-induced fission of U238, were studied at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. The level scheme of As523385 populated in Ge85βγ decay was reconstructed and compared to shell-model calculations. The investigation of the systematics of low-energy levels in N=52 isotones together with shell-model analysis allowed us to provide an estimate of the low-energy structure of the more exotic N=52 isotone Cu81
β and β-n decay of the neutron-rich Ge 84 nucleus
The β-decay properties of the very neutron-rich Ge84 nucleus were studied at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. Several new γ-transitions and levels were added to its decay scheme and the order of the two lowest-lying levels in the daughter As84 was corrected. For the first time γ radiation following β-delayed neutron emission was observed. The shell-model calculations and apparent β transition intensities were used to guide the spin assignment to the As84 levels, in particular for the low-energy part of the level scheme. The new spin-parity (2-) proposed for the ground state of As84 is supported also by the systematics of N=51 isotones
βdecays of \u3csup\u3e92\u3c/sup\u3eRb, \u3csup\u3e96gs\u3c/sup\u3eY, and \u3csup\u3e142\u3c/sup\u3eCs measured with the modular total absorption spectrometer and the influence of multiplicity on total absorption spectrometry measurements
Total absorption spectroscopy is a technique that helps obtain reliable β-feeding patterns of complex decays important for nuclear structure and astrophysics modeling as well as decay heat analysis in nuclear reactors. The need for improved measurements of β-feeding patterns from fission decay products has come to the forefront of experiments that use nuclear reactors as a source of antineutrinos. Here we present more detailed results, in particular the β-decay measurements of 96gsY, and demonstrate the impact of the β-delayed γ multiplicity on the overall efficiency of Modular Total Absorption Spectrometer used at Oak Ridge National Laboratory to study the decays of fission products abundant during a nuclear fuel cycle
Excited states in As 82 studied in the decay of Ge 82
The excited states of odd-odd As82 are studied in the β decay of Ge82. An isotopically pure beam of Ga83 was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and high-resolution electromagnetic separation. The atoms of Ge82 are created after β-delayed neutron emission in the decay of Ga83. The number of Ge82 atoms is found by normalization to the 1348-keV γ ray. Detailed analysis of the decay scheme is compared with shell-model calculations with several commonly used fpg shell interactions
β -decay study of Kr 94
β decay of neutron-rich nuclide Kr94 was reinvestigated by means of a high resolution on-line mass separator and β-γ spectroscopy. In total 22 γ-ray transitions were assigned to the decay of Kr94, and a new isomeric state was identified. The new information allows us to build detailed levels systematics in a chain of odd-odd rubidium isotopes and draw conclusions on nuclear structure for some of the observed states. The discussed level structure affects the evolution of β-decay half-lives for neutron-rich selenium, krypton, and strontium isotopes