21 research outputs found
Shears band with a large dynamic moment of inertia in
High-spin states in 197Bi were studied with the AFRODITE γ-ray array at iThemba LABS using the 181Ta( 22Ne, 6n) reaction at a beam energy of 125 MeV. A new shears band was found and linked to the low-lying states in 197Bi. Its dynamic moment of inertia, , is considerably larger than the of the shears bands in the neighbouring Pb isotopes. This is probably a result of the involvement of an additional high-K
h
9/2 proton orbital
Characterization of quasiparticle states at and beyond stability in ytterbium isotopes: Spectroscopy of
Excited states in 175Yb, 176Yb and 177Yb were populated via the bombardment of a 176Yb target with a 750 MeV 136Xe beam. Gamma-ray decays from these states were measured with the AFRODITE multi-detector spectrometer. The rotational band previously assigned to the ground state of 177Yb has been reassigned to the first-excited state of 175Yb. A new rotational band based on the ground state of 177Yb is presented, and the band based on the K
π = 4- two-quasiparticle state in 176Yb has been identified. Also a candidate for the rotational band based on the K
π = 8-, T
1/2 = 11.4(3) s two-quasiparticle state in 176Yb has been found. Comparisons of gK values derived from in-band branching ratios are consistent with the ν9/2+[624] assignment to the ground state of 177Yb, the ν2{9/2+[624] ⊗ 1/2-[510]} assignment to the K
π = 4- state and with the ν2{9/2+[624] ⊗ 7/2-[514]} assignment to the K
π = 8- metastable excited state in 176Yb
Rotational structures in 196Hg
CITATION: Lawrie, J. J., et al. 2019. Rotational structures in 196Hg. Physical Review C, 100(6):064321, doi:10.1103/PhysRevC.100.064321.The original publication is available at https://journals.aps.org/prcHigh spin states in ¹⁹⁶Hg were populated in the ¹⁹⁸Pt(α,6n) reaction at 65 MeV and γ−γ coincidence measurements were performed using the AFRODITE array at iThemba LABS. The level scheme was extended and new rotational bands were observed. A new dipole band was found. The previously reported dipole band was linked to other known states. Excitation energies, spins, and parities of all bands were determined. The bands were assigned nucleon configurations based on cranked shell model calculations.https://journals.aps.org/prc/abstract/10.1103/PhysRevC.100.064321Publisher's versio
New nanosecond isomers identified with the AFRODITE array
The Recoil Shadow Anisotropy Method for measuring nanosecond lifetimes is being implemented on the AFRODITE array and four new isomers were found in 198,200Bi, 164Ta and 162Lu
Study of fission fragments produced by
This work was performed to understand the structure of neutron-rich fission fragments around the 130 mass region. A thin 235U target was bombarded by a 14N beam with 10 MeV/A from the Separated Sector Cyclotron at the iThemba Laboratory for Accelerator Based Sciences, Cape Town, South Africa. The main goal was to detect and identify fission fragments and to obtain their mass distribution by using solar cell detectors in the AFRODITE (African Omnipurpose Detector for Innovative Techniques and Experiments) spectrometer. The X-rays emitted from fission fragments were detected by LEP (Low Energy Photon) detectors and γ-rays emitted from excited states of the fission fragments were detected by CLOVER detectors in the spectrometer
Study of fission fragments produced by N-14+U-235 reaction
This work was performed to understand the structure of neutron-rich fission fragments around the 130 mass region. A thin U-235 target was bombarded by a N-14 beam with 10 MeV/A from the Separated Sector Cyclotron at the iThemba Laboratory for Accelerator Based Sciences, Cape Town, South Africa. The main goal was to detect and identify fission fragments and to obtain their mass distribution by using solar cell detectors in the AFRODITE (African Omnipurpose Detector for Innovative Techniques and Experiments) spectrometer. The X-rays emitted from fission fragments were detected by LEP (Low Energy Photon) detectors and gamma-rays emitted from excited states of the fission fragments were detected by CLOVER detectors in the spectrometer
Clinical, Environmental, and Serologic Surveillance Studies of Melioidosis in Gabon, 2012–2013
Burkholderia pseudomallei, an environmental gram-negative bacillus, is the causative agent of melioidosis and a bio-threat agent. Reports of B. pseudomallei isolation from soil and animals in East and West Africa suggest that melioidosis might be more widely distributed than previously thought. Because it has been found in equatorial areas with tropical climates, we hypothesized that B. pseudomallei could exist in Gabon. During 2012–2013, we conducted a seroprevalance study in which we set up microbiology facilities at a large clinical referral center and prospectively screened all febrile patients by conducting blood cultures and testing for B. pseudomallei and related species; we also determined whether B. pseudomallei could be isolated from soil. We discovered a novel B. pseudomallei sequence type that caused lethal septic shock and identified B. pseudomallei and B. thailandensis in the environment. Our data suggest that melioidosis is emerging in Central Africa but is unrecognized because of the lack of diagnostic microbiology facilities