0000000000194989
AUTHOR
L. Kucuk
Observation of the 2+ isomer in Co52
We report the first observation of the ${2}^{+}$ isomer in $^{52}\mathrm{Co}$, produced in the $\ensuremath{\beta}$ decay of the ${0}^{+}$, $^{52}\mathrm{Ni}$ ground state. We have observed three $\ensuremath{\gamma}$ rays at 849, 1910, and 5185 keV characterizing the $\ensuremath{\beta}$ de-excitation of the isomer. We have measured a half-life of 102(6) ms for the isomeric state. The Fermi and Gamow-Teller transition strengths for the $\ensuremath{\beta}$ decay of $^{52m}\mathrm{Co}$ to $^{52}\mathrm{Fe}$ have been determined. We also add new information on the $\ensuremath{\beta}$ decay of the ${6}^{+}$, $^{52}\mathrm{Co}$ ground state, for which we have measured a half-life of 112(3) ms.
Characterization of a neutron–beta counting system with beta-delayed neutron emitters
A new detection system for the measurement of beta-delayed neutron emission probabilities has been characterized using fission products with well known β-delayed neutron emission properties. The setup consists of BELEN-20, a 4π neutron counter with twenty 3He proportional tubes arranged inside a large polyethylene neutron moderator, a thin Si detector for β counting and a selftriggering digital data acquisition system. The use of delayed-neutron precursors with different neutron emission windows allowed the study of the effect of energy dependency on neutron, β and β-neutron rates. The observed effect is well reproduced by Monte Carlo simulations. The impact of this dependency on the accura…
Nuclear weak response from the combined study of beta-decay and charge-exchange reaction
Studying the weak nuclear response, especially the Gamow-Teller (GT) transitions, of stable as well as unstable pf-shell nuclei, is one of the key issues in nuclear and astro-nuclear physics. We study the decay half-lives and the GT transitions starting from Tz = ±1 and ±2 mirror nuclei, respectively, by means of β decays and complementary hadronic (3 He , t) charge-exchange reactions. Under the assumption that isospin is a good quantum number, symmetry is expected for mirror nuclei and the GT transitions starting from the mirror nuclei. The half-lives and branching ratios and the measured strength distributions of GT transitions are compared and also combined for the understanding of the …
Characterization of a neutron-beta counting system with beta-delayed neutron emitters
Abstract A new detection system for the measurement of beta-delayed neutron emission probabilities has been characterized using fission products with well known β-delayed neutron emission properties. The setup consists of BELEN-20, a 4π neutron counter with twenty 3He proportional tubes arranged inside a large polyethylene neutron moderator, a thin Si detector for β counting and a self-triggering digital data acquisition system. The use of delayed-neutron precursors with different neutron emission windows allowed the study of the effect of energy dependency on neutron, β and β–neutron rates. The observed effect is well reproduced by Monte Carlo simulations. The impact of this dependency on …
Beta decay of the exotic Tz = - 2, $^{56}$Zn nucleus and half-life of various proton-rich Tz = -1 nuclei
Expérience GANIL/LISE3/EXOGAM; International audience; Preliminary results of an experimental study of the beta -decay of the exotic T$_z$ = - 2, $^{56}$Zn nucleus and other proton-rich T$_z$ = -1 nuclei are presented. The ions were produced at GANIL using fragmentation reactions, separated by the LISE3 spectrometer and implanted in a double-sided silicon strip detector surrounded by Ge detectors. The half-lives of $^{56}$Zn and four T$_z$ = -1 nuclei in the fp-shell have been measured. While the decay of the T$_z$ = -1 nuclei proceeds essentially by -delayed gamma emission, in the case of $^{56}$Zn -delayed proton emission is also observed. Moreover, the exotic -delayed gamma-proton decay …
$\beta $-delayed $\gamma $-proton Decay in $^{56}$Zn: Analysis of the Charged-particle Spectrum
A study of the $\beta$ decay of the proton-rich $T_{z}$ = -2 nucleus $^{56}$Zn has been reported in a recent publication. A rare and exotic decay mode, $\beta$-delayed $\gamma$-proton decay, has been observed there for the first time in the $fp$ shell. Here we expand on some of the details of the data analysis, focussing on the charged particle spectrum.
Observation of theβ-Delayedγ-Proton Decay ofZn56and its Impact on the Gamow-Teller Strength Evaluation
We report the observation of a very exotic decay mode at the proton drip line, the $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-proton decay, clearly seen in the $\ensuremath{\beta}$ decay of the ${T}_{z}=\ensuremath{-}2$ nucleus $^{56}\mathrm{Zn}$. Three $\ensuremath{\gamma}$-proton sequences have been observed after the $\ensuremath{\beta}$ decay. Here this decay mode, already observed in the $sd$ shell, is seen for the first time in the $fp$ shell. Both $\ensuremath{\gamma}$ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.
Observation of the beta-Delayed gamma-Proton Decay of Zn-56 and its Impact on the Gamow-Teller Strength Evaluation
We report the observation of a very exotic decay mode at the proton drip line, the beta-delayed gamma-proton decay, clearly seen in the beta decay of the T-z = -2 nucleus Zn-56. Three gamma-proton sequences have been observed after the beta decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the f p shell. Both. and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.
Beta Decay Study of the Tz=−2 56Zn Nucleus and the Determination of the Half-Lives of a Few fp-shell Nuclei
Abstract This paper concerns the experimental study of the β decay properties of few proton-rich fp -shell nuclei. The nuclei were produced at GANIL in fragmentation reactions, separated with the LISE spectrometer and stopped in an implantation detector surrounded by Ge detectors. The β -delayed gammas, β -delayed protons and the exotic β -delayed gamma-proton emission have been studied. Preliminary results are presented. The decay of the T z = − 2 nucleus 56 Zn has been studied in detail. Information from the β -delayed protons and β -delayed gammas has been used to deduce the decay scheme. The exotic beta-delayed gamma-proton decay has been observed for the first time in the fp -shell. Th…