Electric dipole response of 208Pb from proton inelastic scattering: constraints on neutron skin thickness and symmetry energy

The electric dipole (E1) response of 208Pb has been precisely determined by measuring Coulomb excitation induced by proton scattering at very forward angles. The electric dipole polarizability, defined as inverse energy-weighted sum rule of the E1 strength, has been extracted as 20.1+-0.6 fm^3. The data can be used to constrain the neutron skin thickness of 208Pb to 0.168(+-0.009)_expt(+-0.013)_theo(+-0.021)_est fm, where the subscript "expt" refers to the experimental uncertainty, "theor" to the theoretical confidence band and "est" to the uncertainty associated with the estimation of the symmetry energy at the saturation density. In addition, a constraint band has been extracted in the plane of the symmetry energy (J) and its slope parameter (L) at the saturation density.Comment: 6 pages, 8 figures, revised manuscript submitted to special volume of Eur. Phys. J. A on symmetry energ

Complete dipole response in 208Pb from high-resolution polarized proton scattering at 0°.

At the Research Center for Nuclear Physics, Osaka, Japan, the 208Pb(p,p´) reaction was measured at Ep=295 MeV and scattering angles Θlab= 0° - 10°. A high energy resolution of the order of ΔE/E ≈ 8x10^-5 was achieved, corresponding to ΔE=25-30 keV (FWHM). Cross sections were extracted by a multipole decomposition analysis of the angular distributions. Dominant contributions at very forward angles originate from E1 excitation due to Coulomb projectile-target interaction and spin M1 transitions caused by the spin-isospin part of the proton-nucleus interaction. A separation of these contributions was performed with two independent methods, viz. a multipole decomposition of the angular distributions and utilizing polarization transfer observables. Excellent agreement between both techniques is achieved within errors bars. The B(E1) strength distribution was extracted in the energy range between 5 and 20 MeV. Below the neutron separation energy (Sn = 7.367 MeV) it shows excellent agreement with available (γ,γ´) data and in the region of the giant dipole resonance with photoabsorption experiments. The shape of the angular distributions indicates a structural change of E1 strength below and above 8.2 MeV. The centroid energy and summed B(E1) strength of the PDR are extracted and amount to Ec=7.43(2) MeV and ΣB(E1)=1.54(16) e2fm2, respectively. Previously unobserved strength is found in the region above neutron threshold up to 8.2 MeV. The deduced E1 polarizability in the energy range from 5 to 19 MeV is αD = 18.7(13)fm3/e2. Averaging over all available data a highly precise value of αD = 18.9(5) fm3/e2 can be extracted. As the strong correlations predicted by microscopical models, this puts important constraints on the neutron skin thickness in 208Pb and the density dependence of the symmetry energy. The fine structure of the giant dipole resonance was analyzed with wavelet methods. Characteristic scales at E=100 keV, 340 keV, 520 keV, 1 MeV, and 2.1 MeV can be found. A comparison with microscopic calculations including the coupling to 2p-2h states suggests Landau damping as the dominant mechanism contributing to the decay width. Level densities of 1- states were extracted with a fluctuation analysis in the giant dipole resonance region. All phenomenological and microscopic models fail to describe the level densities in 208Pb, except for a version of the back-shifted Fermi gas model allowing for additional phenomenological parameters in local mass regions

pH-sensitive Hybrid Hydrogel Materials with Incorporated Nanoparticles

Synthesis and physico-chemical studies of new promising hybrid hydrogels based on polyvinyl alcohol (PVA) acetales and copolymer hydrogels based on vinyl monomers have been studied. Acrylamide, N-Isopropylacrylamide and Acrylic acid were used as components of interpenetrating networks based on PVA acetals. Sponge acetales of polyvinyl alcohol were used as enforcing net. Study of swelling kinetics as compared to solvents of various nature (water in various pH, ethanol, toluene etc) was carried out. IR comparative spectra were obtained for different composites. High anti-bacterial action of the synthesized nanocomposites containing silver towards gram-positive and gram-negative bacteria has been demonstrated

E2 strengths and transition radii difference of one-phonon 2+ states of 92Zr from electron scattering at low momentum transfer

Background: Mixed-symmetry 2+ states in vibrational nuclei are characterized by a sign change between dominant proton and neutron valence-shell components with respect to the fully symmetric 2+ state. The sign can be measured by a decomposition of proton and neutron transition radii with a combination of inelastic electron and hadron scattering [C. Walz et al., Phys. Rev. Lett. 106, 062501 (2011)]. For the case of 92Zr, a difference could be experimentally established for the neutron components, while about equal proton transition radii were indicated by the data. Method: Differential cross sections for the excitation of one-phonon 2+ and 3- states in 92Zr have been measured with the (e,e') reaction at the S-DALINAC in a momentum transfer range q = 0.3-0.6 fm^(-1). Results: Transition strengths B(E2;2+_1 -> 0+_1) = 6.18(23), B(E2; 2+_2 -> 0+_1) = 3.31(10) and B(E3; 3-_1 -> 0+_1) = 18.4(11) Weisskopf units are determined from a comparison of the experimental cross sections to quasiparticle-phonon model (QPM) calculations. It is shown that a model-independent plane wave Born approximation (PWBA) analysis can fix the ratio of B(E2) transition strengths to the 2+_(1,2) states with a precision of about 1%. The method furthermore allows to extract their proton transition radii difference. With the present data -0.12(51) fm is obtained. Conclusions: Electron scattering at low momentum transfers can provide information on transition radii differences of one-phonon 2+ states even in heavy nuclei. Proton transition radii for the 2+_(1,2) states in 92Zr are found to be identical within uncertainties. The g.s. transition probability for the mixed-symmetry state can be determined with high precision limited only by the available experimental information on the B(E2; 2+_1 -> 0+_1) value.Comment: 14 pages, 5 figures, submitted to Phys. Rev. C, revised manuscrip

ANÁLISE LINGUO-COGNITIVA DE UM TEXTO LITERÁRIO: MEIOS LINGUÍSTICOS DE EXPRESSÃO DE CONCEITOS E IMAGENS

The work is devoted to the study of the linguo-cognitive analysis of the literary text in the aspect of linguistic means of expressing concepts and images. The relevance of this article is due to the growing attention to the analysis of the literary text using the methods and techniques of cognitive linguistics. The main aspects of cognitive linguistics, lingua-cognitive analysis, and text as an object of cognitive linguistics research are widely covered in the work. The main features of the literary text, its components, and lingua-cognitive analysis of linguistic means of expressing concepts and images are defined. The purpose of the research is to reveal the lingo-cognitive analysis of the literary text in the aspect of linguistic means of expressing concepts and images. The object of research is a literary text as material for lingua-cognitive research. Research methods. Such research methods such as description, analysis and synthesis, comparison, generalization, cognitive analysis, linguistic analysis, and modelling were used in the work. The article reveals the lingua-cognitive analysis of the literary text in terms of linguistic means of expressing concepts and images. The essence of the concept of “cognitive linguistics” and the main aspects of this phenomenon are characterized. The interpretation of the term “lingua-cognitive analysis” is defined. The essence of the “text” concept and the classification features of the text are described. The scientific work describes the features of the literary text. The components of the literary text influencing the lingua-cognitive analysis are characterized. Such elements of the literary text as image, concept, character, and evaluation are summarized.O trabalho dedica-se ao estudo da análise linguo-cognitiva de um texto literário no aspecto dos meios linguísticos de expressão de conceitos e imagens. A relevância deste artigo se deve à crescente atenção dada à análise do texto literário utilizando os métodos e técnicas da linguística cognitiva. Os principais aspectos da linguística cognitiva, da análise linguística-cognitiva e do texto como objeto de pesquisa em linguística cognitiva são amplamente abordados no trabalho. São definidas as principais características do texto literário, seus componentes e a análise linguístico-cognitiva dos meios linguísticos de expressão de conceitos e imagens. O objetivo da pesquisa é revelar a análise lingocognitiva de um texto literário no aspecto dos meios linguísticos de expressão de conceitos e imagens. O objeto de pesquisa é um texto literário como material para pesquisas linguísticas e cognitivas. Métodos de pesquisa. Métodos de pesquisa como descrição, análise e síntese, comparação, generalização, análise cognitiva, análise linguística e modelagem foram utilizados no trabalho. O artigo revela a análise linguístico-cognitiva do texto literário em termos de meios linguísticos de expressão de conceitos e imagens. Caracteriza-se a essência do conceito de “linguística cognitiva” e os principais aspectos desse fenômeno. A interpretação do termo “análise linguístico-cognitiva” é definida. A essência do conceito de “texto” e as características de classificação do texto são descritas. O trabalho científico descreve as características do texto literário. São caracterizados os componentes do texto literário que influenciam a análise linguística-cognitiva. Elementos do texto literário como imagem, conceito, personagem e avaliação são resumidos

Pygmies, Giants, and Skins

Understanding the equation of state (EOS) of neutron-rich matter is a central goal of nuclear physics that cuts across a variety of disciplines. Indeed, the limits of nuclear existence, the collision of energetic heavy ions, the structure of neutron stars, and the dynamics of core-collapse supernova all depend critically on the nuclear-matter EOS. In this contribution I focus on the EOS of cold baryonic matter with special emphasis on its impact on the structure, dynamics, and composition of neutron stars. In particular, I discuss how laboratory experiments on neutron skins as well as on Pygmy and Giant resonances can help us elucidate the structure of these fascinating objects.Comment: Invited Talk given at the 11th International Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1, 2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference Series (JPCS

Peculiarities of the functioning of verbs in modern artistic discourse (on the material of texts of ukrainian and english literature)

The objective of this research is to examine the peculiarities of the functioning of verbs in modern artistic discourse, focusing on texts from Ukrainian and English literature. This study aims to establish the manner in which verb forms and their grammatical and stylistic meanings serve as markers of a text's affiliation with the artistic style. The research methodology is complex. The descriptive method, analysis, and synthesis have served to analyze the theoretical material. Moreover, semi-component, structural analysis, and discourse analysis guidelines have been applied. The study hypothesizes that verbs and their forms perform different types of stylistic functions and participate in the formation of the artistic discourse of modern Ukrainian literatur