11 research outputs found
Spatial analysis of locational conflicts: case study: locational conflicts generated by the expansion of built up surfaces in the northern area of Bucharest, Romania
The aim of this paper is to identify and analyze land use conflicts existing in the northern area of Bucharest and to spatially model their impact on the expandint residential areas. The main objectives are: 1) to analyze the dynamics of built up surfaces between 1975-2010; 2) to analyze the spatial and temporal dynamic of locational conflicts and 3) to spatially model the impact of locational conflicts on residential areas.Peer Reviewe
Investigation of the Δn = 0 selection rule in Gamow-Teller transitions : The β-decay of 207 Hg
Gamow-Teller β decay is forbidden if the number of nodes in the radial wave functions of the initial and final states is different. This Δn=0 requirement plays a major role in the β decay of heavy neutron-rich nuclei, affecting the nucleosynthesis through the increased half-lives of nuclei on the astrophysical r-process pathway below both Z=50 (for N>82) and Z=82 (for N>126). The level of forbiddenness of the Δn=1ν1g 9/2 →π0g 7/2 transition has been investigated from the β − decay of the ground state of 207 Hg into the single-proton-hole nucleus 207 Tl in an experiment at the ISOLDE Decay Station. From statistical observational limits on possible γ-ray transitions depopulating the π0g 7/2 −1 state in 207 Tl, an upper limit of 3.9×10 −3 % was obtained for the probability of this decay, corresponding to logft>8.8 within a 95% confidence limit. This is the most stringent test of the Δn=0 selection rule to date
Spatial analysis of locational conflicts: case study: locational conflicts generated by the expansion of built up surfaces in the northern area of Bucharest, Romania
The aim of this paper is to identify and analyze land use conflicts existing in the northern area of Bucharest and to spatially model their impact on the expandint residential areas. The main objectives are: 1) to analyze the dynamics of built up surfaces between 1975-2010; 2) to analyze the spatial and temporal dynamic of locational conflicts and 3) to spatially model the impact of locational conflicts on residential areas.Peer Reviewe
Search for isospin-symmetry breaking in the isovector triplet
The assignment of the first state in Ga has long been debated, due to its implications in triplet energy difference systematics in this mass region. An experiment has been performed at the IFIN-HH 9-MV Tandem accelerator using the ROSPHERE array in a mixed configuration of LaBr(Ce) and HPGe detectors, as well as an additional array of liquid scintillator neutron detectors. Excited states in Ga were populated through a fusion-evaporation channel and an anisotropy ratio was obtained from neutron-filtered HPGe statistics of transitions observed at different angles. A state has been confirmed at an excitation energy of 978.1(1) keV. Theoretically, the interplay between isospin-symmetry breaking and shape-coexistence effects in the isovector triplet is self-consistently treated within the beyond-mean-field complex excited Vampir variational model with symmetry projection before variation using an effective interaction obtained from a G matrix based on the charge-dependent Bonn CD potential adding the Coulomb interaction between the valence protons. Results are presented on Coulomb energy differences, mirror energy differences, triplet energy differences, and the superallowed Fermi decay of the ground state of Ge and Ga
Collective properties of neutron-deficient Nd isotopes: Lifetime measurements of the yrast states in Nd
International audienceLifetimes of the low-energy levels in Nd136, populated in the reaction Te124(O16,4n), were measured with the ROSPHERE array at the Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest-Magurele. The data were analyzed using the recoil distance Doppler shift method, and, in the cases where lifetimes were τ⩽1 ps, Doppler attenuation effects were taken into account. The deduced electromagnetic transition probabilities are discussed in the framework of the five-dimensional collective Hamiltonian (5DCH) theoretical model implemented with the D1S Gogny force, and detailed systematics of several observables in the even-even Nd isotopic chain are presented that highlight the transitional character of the neutron-deficient Nd isotopes. The 5DCH predictions are in overall good agreement with the present experimental results
A time-of-flight correction procedure for fast-timing data of recoils with varying implantation positions at a spectrometer focal plane
Fast-timing measurements at the focal plane of a separator can suffer from poor timing resolution. This is due to
the variations in time-of-flight (ToF) for photons travelling to a given detector, which arise from the changes in the
implantation positions of the recoil nuclei emitting the γ rays of interest. In order to minimise these effects on timing
measurements, a procedure is presented that improves fast-timing data by performing ToF corrections on an event-by-event
basis. This method was used to correct data collected with an array of eight LaBr3 detectors, which detected γ rays
from spatially distributed 138Gd recoil-implants at the focal plane of the Recoil-Ion-Transport-Unit (RITU) spectrometer.
The Generalised Centroid Difference (GCD) method was used to extract a lifetime from data in conjunction with a new
procedure to calibrate the time walk. The lifetime of the first 2+ state in 138Gd, populated by the decay of the Kπ = 8−
isomeric state, was measured to be 229(24) ps using the ToF-corrected data, which is consistent within three standard
deviations to the literature value. The results together with Monte-Carlo simulations show that the ToF correction
procedure reduced the uncertainty in the measured lifetimes by 3 % in the case of the spatially distributed nuclei at the
focal plane of RITU. However, ∼12 % has been estimated for a similar experiment when using a larger focal plane i.e. the
Super-FRS at the FAIR facility.peerReviewe