0000000000049946
AUTHOR
José Antonio Briz
Total absorption γ -ray spectroscopy of niobium isomers
15 pags. 17 figs., 5 tabs.
Relative proton andγwidths of astrophysically important states in30S studied in theβ-delayed decay of31Ar
Resonances just above the proton threshold in S-30 affect the P-29(p, gamma)S-30 reaction under astrophysical conditions. The (p,gamma)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances. We present here a method for finding the ratio between the proton and gamma partial widths of resonances in S-30. The widths are determined from the beta 2p- and beta p gamma-decay of Ar-31, which is produced at the ISOLDE radioactive ion beam facility at the European research organization CERN. Experimental limits on the ratio between the proton and gamma partial widths for astrophysical relevant levels in S-30 have been found for the first time. A le…
Total absorption studies of high priority decays for reactor applications: 86Br and 91Rb
Preliminary results from beta decay studies of nuclei that are important for reactor applications are presented. The beta decays have been studied using the total absorption technique (TAS) and the pure beams provided by the JYFLTRAP system at the IGISOL facility of the University of Jyväskylä. peerReviewed
Beta delayed alpha emission from the neutron deficient rare earth isotopes [sup 152]Tm and [sup 150]Ho
The study of beta‐delayed proton emission is a well known method to aid the determination of the beta strength distribution in nuclei far from the stability line. At the neutron deficient side of the nuclear chart the process of proton or alpha emission from excited states is energetically allowed when one goes far enough from stability. However, beta‐delayed alphas have seldom been measured for nuclei heavier than A = 20. Here we present a study of the beta‐delayed alpha‐particle emission from 152Tm and 150Ho and their importance in the full B(GT) distribution. © 2011 American Institute of Physics
Total absorption γ -ray spectroscopy of the β -delayed neutron emitters I137 and Rb95
The decays of the β-delayed neutron emitters I137 and Rb95 have been studied with the total absorption γ-ray spectroscopy technique. The purity of the beams provided by the JYFLTRAP Penning trap at the ion guide isotope separator on-line facility in Jyvaskyla allowed us to carry out a campaign of isotopically pure measurements with the decay total absorption γ-ray spectrometer, a segmented detector composed of 18 NaI(Tl) modules. The contamination coming from the interaction of neutrons with the spectrometer has been carefully studied, and we have tested the use of time differences between prompt γ rays and delayed neutron interactions to eliminate this source of contamination. Due to the s…
Multiparticle emission in the decay ofAr31
A multihit capacity setup was used to study the decay of the dripline nucleus Ar-31, produced at the ISOLDE facility at CERN. A spectroscopic analysis of the beta-delayed three-proton decay of Ar-31 is presented for the first time together with a quantitative analysis of the beta-delayed 2p gamma decay. A new method for determination of the spin of low-lying levels in the beta p daughter 30S using proton-proton angular correlations is presented and used to determine that the spin of the 5.2-MeV level is most likely 3(+) with 4(+) also possible. The half-life of Ar-31 is found to be 15.1(3) ms. An improved analysis of the Fermi beta strength including the beta 3p-decay mode gives a total mea…
Determination of β -decay ground state feeding of nuclei of importance for reactor applications
12 pags., 6 figs., 3 tabs.
Strong γ-ray emission from neutron unbound states populated in β-decay: Impact on (n,γ) cross-section estimates
J. L. Taín et al. -- 6 pags., 7 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0
Decay of theN=126, Fr213nucleus
gamma rays following the EC/beta(+) and alpha decay of the N = 126, Fr-213 nucleus have been observed at the CERN isotope separator on-line (ISOLDE) facility with the help of gamma-ray and conversion-electron spectroscopy. These gamma rays establish several hitherto unknown excited states in Rn-213. Also, five new a-decay branches from the Fr-213 ground state have been discovered. Shell model calculations have been performed to understand the newly observed states in Rn-213.
Structures ofPo201andRn205from EC/β+-decay studies
Several low-lying excited states in {sub 86}{sup 205}Rn{sub 119} and {sub 84}{sup 201}Po{sub 117} were identified for the first time following EC/{beta}{sup +} decay of {sup 205}Fr and {sup 201}At, respectively, using {gamma}-ray and conversion electron spectroscopy at the CERN isotope separator on-line (ISOLDE) facility. The EC/{beta}{sup +} branch from {sup 205}Fr was measured to be 1.5(2)%. The excited states of the daughter nuclei are understood in terms of the odd nucleon coupling to the neighboring even-even core. The neutron single-particle energies of the p{sub 3/2} orbital relative to the f{sub 5/2} ground state in {sup 205}Rn, and the f{sub 5/2} orbital relative to the p{sub 3/2} …
Shapes ofPb192,190ground states fromβ-decay studies using the total-absorption technique
The beta decay of Pb-192,Pb-190 has been studied using the total absorption technique at the ISOLDE (CERN) facility. The beta-decay strength deduced from the measurements, combined with QRPA theoretical calculations, allow us to infer that the ground states of the Pb-192,Pb-190 isotopes are spherical. These results represent the first application of the shape determination method using the total absorption technique for heavy nuclei and in a region where there is considerable interest in nuclear shapes and shape effects.
Summation Calculations for Reactor Antineutrino Spectra, Decay Heat and Delayed Neutron Fractions Involving New TAGS Data and Evaluated Databases
9 pags., 3 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0
Characterization of a cylindrical plastic {\beta}-detector with Monte Carlo simulations of optical photons
V. Guadilla et al. -- 5 pags., 8 figs., tab.
TAGS measurements of $^{100}$Nb ground and isomeric states and $^{140}$Cs for neutrino physics with the new DTAS detector
V. Guadilla et al. -- 4 pags., 6 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0
Disentangling decaying isomers and searching for signatures of collective excitations in β decay
6 pags., 3 figs., 1 tab. -- 27th International Nuclear Physics Conference (INPC2019) 29 July - 2 August 2019, Glasgow, UK