0000000000335942
AUTHOR
D. Bucurescu
Nuclear structure of 131Te studied with (n,γ) and reactions
Abstract The structure of 131 Te has been investigated with the 130 Te( n , γγ ) 131 Te reaction using thermal neutrons and with the 130 Te( d , p ) 131 Te reaction using polarized deuterons with energy E d =18 MeV. About 290 levels were identified in most cases including spin, parity and γ -decay. The γ -decay scheme after neutron capture is essentially complete containing about 100% of the decay of the capture state and about 100% of the population of the 11/2 − isomer and of the ground state. The scheme includes 42 primary transitions with energies between 750 keV and 2500 keV. The experimental level scheme is compared with predictions of the Interacting Boson–Fermion model (IBFM) and of…
Nuclear structure of 127Te studied with (n,γ) and (d→,p) reactions and interpreted with IBFM and QPM
Abstract The nuclear structure of 127Te has been investigated with the Te 126 ( n , γ γ ) Te 127 reaction using thermal neutrons and with the Te 126 ( d → , p ) Te 127 reaction at E d = 20 MeV . About 190 levels were identified in a region to 4.1 MeV excitation energy, in most cases including spin, parity and γ-decay. The γ-decay scheme after neutron capture is essentially complete containing about 100% of the population of the 11 / 2 − isomer and of the ground state. The thermal neutron capture cross section and isomer production of the 11 / 2 − state at 88.3 keV were determined to be 0.44(6) b and 0.069(10) b, respectively. The neutron binding energy was determined to be 6287.6(1) keV. A …
Electromagnetic transition rates in theN=80nucleus58138Ce
The half-life of the Iπ=6+ yrast state at Ex=2294 keV in 138Ce has been measured as T1/2=880(19) ps using the fast-timing γ-ray coincidence method with a mixed LaBr3(Ce)-HPGe array. The excited states in 138Ce have been populated by the 130Te(12C,4n) fusion-evaporation reaction at an incident beam energy of 56 MeV. The extracted B(E2;61+→41+)=0.101(24) W.u. value is compared with the predictions of truncated basis shell model calculations and with the systematics of the region. This shows an anomalous behavior compared to the neighboring isotonic and isotopic chains. Half-lives for the yrast 5-, 11+ and 14+ states in 138Ce have also been determined in this work.
High-spin structure of ^{95}Pd
The level scheme of the neutron-deficient nucleus ${}^{95}$Pd has been studied with the ${}^{58}$Ni + ${}^{40}$Ca fusion-evaporation reaction at 135 MeV with the GASP $\ensuremath{\gamma}$-ray array, the ISIS silicon ball, and the N-ring neutron detector. Excited levels with spins at least up to $\frac{45}{2}\ensuremath{\hbar}$ are reported for both parities. The observed experimental data are compared to large-scale shell-model calculations.
Oblate Collectivity in the Yrast Structure of 194Pt
A deep inelastic reaction using a 460 MeV 82Se beam incident upon a thick 192Os target was performed at the Legnaro National Laboratory, Italy. The resulting γ-decays were measured using the GASP array. Results for 194Pt extend the known level scheme of the yrast structure from spin I = (12 ħ) to (20 ħ). The irregularities in the sequence of the new transition energies and total Routhian surface calculations show a breakdown in collectivity with an yrast oblate shape remaining to high spin. Rubio Barroso, Berta, Berta.Rubio@ific.uv.es
Precision Lifetime Measurements Using LaBr3 Detectors With Stable and Radioactive Beams
A range of high resolution gamma-ray spectroscopy measurements have been carried out using arrays which include a number of Cerium-doped Lanthanum-Tribromide (LrBr3 (Ce)) scintillation detectors used in conjunction with high-resolution hyper-pure germanium detectors. Examples of the spectral and temporal responses of such set-ups, using both standard point radioactive sources 152 Eu and 56 Co, and in-beam fusionevaporation reaction experiments for precision measurements of nuclear excited states in 34 P and 138 Ce are presented. The current and future use of such arrays at existing (EURICA at RIKEN) and future (NUSTAR at FAIR) secondary radioactive beam facilities for precision measurements…
Electromagnetic Transition Rate Measurements in theN=80 Isotone,138Ce
A study of intrinsic state halflife measurements in the N=80 nucleus 138Ce has been made using the 130Te(12C,4n)138Ce fusion evaporation reaction at beam energy of 56 MeV. The fast-timing gamma-ray coincidence method was used with a mixed LaBr3(Ce)-HPGe array to establish the lifetimes of the yrast 6+ state at 2294 keV, the Iπ=5− state at 2218 keV, the Iπ=11+ state at 3943 keV and the 14+ state at that at 5312 keV, all of which are in the sub nanosecond regime. Reduced transition probabilities have been calculated for the electromagnetic decays from these states.
Lifetime measurements in mirror nuclei31S and31P: A test for isospin mixing
Using the 20Ne + 12C fusion-evaporation reaction at E20Ne = 33 MeV and the multidetector array GASP in conjuction with the EUCLIDES charged particle detector, angular correlations of coincident pairs of γ transitions and lifetimes in mirror nuclei 31S and 31P have been measured at the Piave-Alpi accelerator of the Laboratori Nazionali di Legnaro. A comparison of the determined B(E1) strengths of the analog mirror 7/2− → 5/2+ transitions indicates the presence of a violation of isospin symmetry.
Interaction position resolution simulations and in-beam measurements of the AGATA HPGe detectors
WOS: 000290082600015
AGATA-Advanced GAmma Tracking Array
WOS: 000300864200005