Search results for "decay [meson]"
showing 10 items of 152 documents
β-delayed fission andαdecay ofAt196
2016
A nuclear-decay spectroscopy study of the neutron-deficient isotope $^{196}\mathrm{At}$ is reported where an isotopically pure beam was produced using the selective Resonance Ionization Laser Ion Source and On-Line Isotope Mass Separator (CERN). The fine-structure $\ensuremath{\alpha}$ decay of $^{196}\mathrm{At}$ allowed the low-energy excited states in the daughter nucleus $^{192}\mathrm{Bi}$ to be investigated. A $\ensuremath{\beta}$-delayed fission study of $^{196}\mathrm{At}$ was also performed. A mixture of symmetric and asymmetric fission-fragment mass distributions of the daughter isotope $^{196}\mathrm{Po}$ (populated by $\ensuremath{\beta}$ decay of $^{196}\mathrm{At}$) was deduce…
First β -decay scheme of Nb107 : New insight into the low-energy levels of Mo107
2019
Monoisotopic samples of $^{107}\mathrm{Nb}$ nuclei, produced in the proton-induced fission of $^{238}\mathrm{U}$ and separated using the IGISOL mass separator coupled to a Penning trap, were used to perform $\ensuremath{\beta}$- and $\ensuremath{\gamma}$-coincidence spectroscopy of $^{107}\mathrm{Mo}$. Gamma transitions and excited levels in $^{107}\mathrm{Mo}$ were observed in $\ensuremath{\beta}$ decay for the first time. Spin and parity $1/{2}^{+}$ for the ground state of $^{107}\mathrm{Mo}$ is proposed, to replace the previous $5/{2}^{+}$ assignment. The experimental $\ensuremath{\beta}$-decay half-life of $^{107}\mathrm{Nb}$ was estimated to be $0.27\ifmmode\pm\else\textpm\fi{}0.02$ s.
β decay of Cd127 and excited states in In127
2019
A dedicated spectroscopic study of the β decay of 127Cd was conducted at the IGISOL facility at the University of Jyvaskyla. Following high-resolution mass separation in a Penning trap, β-γ-γ coincidences were used to considerably extend the decay scheme of 127In. The β-decaying 3/2+ and 11/2- states in 127Cd have been identified with the 127Cd ground state and the 283-keV isomer. Their respective half-lives have been measured to 0.45(+12-8)s and 0.36(4) s. The experimentally observed β feeding to excited states of 127In and the decay scheme of 127In are discussed in conjunction with large-scale shell-model calculations.
Beta decay of neutron-rich Co: Probing single-particle states at and above the N=40 subshell closure
1999
Neutron-rich Co nuclei with A=66–70 were produced by the laser-ionization isotope-separation on-line method. The β decay from these nuclei has been studied. A case example is given by reporting on the observed decay scheme of 68Co. The half life of the ground-state decay of this nucleus was measured to be 0.21(3) seconds. In addition, a new β decaying isomer half life of 1.16(25) seconds was discovered. The level scheme of 68Ni has been significantly extended, and an interpretation of the observed levels is made by assuming that the N=40 gap has the characteristics of a shell closure.
Beta decay of the new isotope101Sn
1995
The very neutron-deficient isotope 101Sn was produced in a 50Cr(58Ni, 2p5n) reaction and its decay properties were determined for the first time. By using chemically selective ion sources of an on-line mass separator, the energy spectrum and the half-life (3 ± 1 s) of beta-delayed protons of 101Sn were measured. These results are compared to theoretical predictions.
Precise energies of gamma rays from the 230Th and 228Th decay
1977
Abstract Energies up to 300 keV of prominent gamma rays from the decay of 230 Th, 228 Th and some of the 228 Th descendants have been precisely measured by use of Ge(Li) detectors.
Competing Decay Modes of a High-spin Isomer in the Proton-unbound Nucleus $^{158}$Ta
2015
An isomeric state at high spin and excitation energy was recently observed in the proton-unbound nucleus 158Ta. This state was observed to decay by both α and γ decay modes. The large spin change r ...
Competition Between Beta and Double Beta Decay in 48Ca and 96Zr
2000
Highly forbidden beta decays of 48Ca and 96Zr are studied and their relative importance as compared to the double beta decay of these nuclei is evaluated. 48Ca and 96Zr are the only naturally occurring nuclei in which these processes can occur simultaneously. Although usually ordinary beta decay overwhelms double beta decay unless the former is energetically forbidden, in these cases the high degree of forbiddenness and small release of kinetic energy makes the half-lives of these modes comparable to each other.
Total absorption spectroscopy study of the β decay of Br86 and Rb91
2017
The beta decays of 86Br and 91Rb have been studied using the total absorption spectroscopy technique. The radioactive nuclei were produced at the IGISOL facility in Jyvaskyla and further purified using the JYFLTRAP. 86Br and 91Rb are considered high priority contributors to the decay heat in reactors. In addition 91Rb was used as a normalization point in direct measurements of mean gamma energies released in the beta decay of fission products by Rudstam et al. assuming that this decay was well known from high-resolution measurements. Our results shows that both decays were suffering from the Pandemonium effect and that the results of Rudstam et al. should be renormalized.
The T[sub z] = −1→ T[sub z] =0 beta decays and comparison with Charge Exchange reactions
2011
Gamow‐Teller (GT) transitions can be studied in both β decay and charge exchange (CE) reactions. If isospin is a good quantum number, then the Tz = −1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the Tz = −1 fp‐shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (3He, t) measurements on the mirror Tz = +1 target nuclei studied in high resolution at RCNP, Osaka. The β decay experiments were performed as part of the STOPPED beam RISING campaign at GSI.