Search results for "moments"
showing 10 items of 151 documents
Neutron halos in the excited states of 12B
2018
The differential cross sections of the 11B(d,p) 12B reaction leading to formation of the 1+ ground state and the 0.95-MeV 2+, 1.67-MeV 2−, 2.62-MeV 1−, 2.72-MeV 0+, and 3.39-MeV 3− excited states of 12B are measured at Ed = 21.5 MeV. The analysis of the data is carried out within the coupled-reaction-channels method for the direct neutron transfer and the Hauser-Feshbach formalism of the statistical compound-nucleus model. The spectroscopic factors, asymptotic normalization coefficients, and rms radii of the last neutron in all states studied are deduced. The existence of the neutron halos in the 1.67-MeV 2− and 2.62-MeV 1− states is found, consistent with the earlier published data. New in…
Democracy in Constituent Moments: Exploring the Spanish Constitutional Debate of 1931 through Political Theory and Conceptual History
2019
This paper aims to answer the question of why constituent moments are relevant to political theory. It hypothesises the Spanish constitutional debate of 1931 as a case of conceptual innovation in parliamentary politics by arguing that debates in constituent moments entail a special kind of parliamentary argumentation when new political regimes are established. There, all sorts of theoretical, normative, historical, and institutional aspects are discussed to deliberate on the future character and functioning of a political regime. From a methodological point of view, this analysis draws on the revision of arguments and political terms used by MPs during the Spanish constituent assembly of 19…
Mappatura del deflusso annuo superficiale in Sicilia
2007
Nella risoluzione di numerosi problemi pratici dell’idrologia delle acque superficiali è importante poter far affidamento su informazioni relative ai deflussi che siano contemporaneamente affidabili e diffuse sul territorio.La creazione di uno strumento capace di restituire il deflusso e soprattutto la portata che attraversa una determinata sezione di un corso d’acqua è di fondamentale importanza sia per la pianificazione delle risorse idriche in una data regione sia per l’individuazione delle possibili zone soggette al rischio della desertificazione. La stima del deflusso superficiale permette inoltre la determinazione dei concentrazione degli inquinanti, concentrati o diffusi, nei corpi i…
Directionlets: Anisotropic Multidirectional representation with separable filtering
2006
In spite of the success of the standard wavelet transform (WT) in image processing in recent years, the efficiency of its representation is limited by the spatial isotropy of its basis functions built in the horizontal and vertical directions. One-dimensional (1-D) discontinuities in images (edges and contours) that are very important elements in visual perception, intersect too many wavelet basis functions and lead to a nonsparse representation. To efficiently capture these anisotropic geometrical structures characterized by many more than the horizontal and vertical directions, a more complex multidirectional (M-DIR) and anisotropic transform is required. We present a new lattice-based pe…
Space-Frequency Quantization for Image Compression With Directionlets
2007
The standard separable 2-D wavelet transform (WT) has recently achieved a great success in image processing because it provides a sparse representation of smooth images. However, it fails to efficiently capture 1-D discontinuities, like edges or contours. These features, being elongated and characterized by geometrical regularity along different directions, intersect and generate many large magnitude wavelet coefficients. Since contours are very important elements in the visual perception of images, to provide a good visual quality of compressed images, it is fundamental to preserve good reconstruction of these directional features. In our previous work, we proposed a construction of critic…
Beyond life-skills: talented athletes, existential learning and (Un)learning the life of an athlete
2022
Following developments in educational discourse more broadly, learning discourses in youth sport have been shaped by outcome-based and instrumental goals of developing useful life-skills for ‘successful’ lives. There is, however, a need to expand such traditional understandings of sport-based youth development, which we undertook by exploring existential learning in sport through encountering discontinuity. We conducted in-depth qualitative research with 16 Finnish athletes (seven men/nine women, aged 19–20), five of whom had recently disengaged from the athlete development pathway. In the interviews, we used creative non-fiction vignettes to invite reflections on learning experiences in sp…
On the Fast and Rigorous Analysis of Compensated Waveguide Junctions Using Off-Centered Partial-Height Metallic Posts
2007
In this paper, we present an efficient and rigorous method, based on the 3-D boundary integral-resonant-mode expansion technique, for the analysis of multiport rectangular waveguide junctions compensated with partial-height cylindrical metallic posts. The electrical performance of a great variety of commonly used wideband microwave circuits has been improved drastically thanks to the introduction of a new design parameter, i.e., the relative position of the metallic post in the structure. To the authors' knowledge, this parameter has not been taken into account in previous studies concerning compensated junctions using partial-height metallic posts. The developed tool has been successfully …
Shape coexistence in the neutron-deficient even-even Hg182-188 isotopes studied via Coulomb excitation
2014
Coulomb-excitation experiments to study electromagnetic properties of radioactive even-even Hg isotopes were performed with 2.85 MeV/nucleon mercury beams from REX-ISOLDE. Magnitudes and relative signs of the reduced E2 matrix elements that couple the ground state and low-lying excited states in Hg182-188 were extracted. Information on the deformation of the ground and the first excited 0+ states was deduced using the quadrupole sum rules approach. Results show that the ground state is slightly deformed and of oblate nature, while a larger deformation for the excited 0+ state was noted in Hg182,184. The results are compared to beyond mean field and interacting-boson based models and interp…
Nuclear moments of indium isotopes reveal abrupt change at magic number 82
2022
In spite of the high-density and strongly correlated nature of the atomic nucleus, experimental and theoretical evidence suggests that around particular 'magic' numbers of nucleons, nuclear properties are governed by a single unpaired nucleon1,2. A microscopic understanding of the extent of this behaviour and its evolution in neutron-rich nuclei remains an open question in nuclear physics3-5. The indium isotopes are considered a textbook example of this phenomenon6, in which the constancy of their electromagnetic properties indicated that a single unpaired proton hole can provide the identity of a complex many-nucleon system6,7. Here we present precision laser spectroscopy measurements perf…
Spins and magnetic moments of 58;60;62;64Mn ground states and isomers
2015
The odd-odd 54;56;58;60;62;64Mn isotopes (Z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous tentative ground state spin assignments of 58;60;62;64Mn are now firmly determined to be I = 1 along with an I = 4 assignment for the isomeric states in 58;60;62Mn. The I = 1 magnetic moments show a decreasing trend with increasing neutron number while the I = 4 moments remain quite constant between N = 33 and N = 37. The results are compared to large-scale shell-model calculations using the GXPF1A and LNPS effective interactions. The excellen…