Energy levels and radiative rates for transitions in Ar XIII, Ar XIV and Ar XV

Energies for 524 levels of Ar XIII, 460 levels of Ar XIV and 156 levels of Ar XV have been calculated using the GRASP code of Dyall et al. (1989). Additionally, radiative rates, oscillator strengths, and line strengths are calculated for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), and magnetic quadrupole (M2) transitions among these levels. Comparisons are made with the limited results available in the literature, and the accuracy of the data is assessed. Our energy levels are estimated to be accurate to better than 1%, whereas results for other parameters are probably accurate to better than 20%. Additionally, the level lifetimes derived from our radiative rates are in excellent agreement with measured values.

Inner-shell photoexcitation of Fe XV and Fe XVI

The configuration-interaction method as implemented in the computer code CIV3 is used to determine energy levels, electric dipole radiative transition wavelengths, oscillator strengths and transition probabilities for inner-shell excitation of transitions in Fe XV and Fe XVI. Specifically, transitions are considered of the type 1s(2) 2s(2) 2p(6) 3s(2) -1s(2) 2s(2) 2p(5) 3l3l' 3l" (l, l' and l" = s,p or d) in FeXV and 1s(2) 2s(2) 2p(6) 3s- 1s(2) 2s(2) 2p(5) 3l3l' (l and l' = s,p or d) in FeXVI, using the relativistic Breit-Pauli approach. An assessment of the accuracy of the derived atomic data is performed.

An investigation of Fe XV emission lines in solar flare spectra

Previously, large discrepancies have been found between theory and observation for Fe XV emission line ratios in solar flare spectra covering the 224-327 angstrom wavelength range, obtained by the Naval Research Laboratory's S082A instrument on board Skylab. These discrepancies have been attributed to either errors in the adopted atomic data or the presence of additional atomic processes not included in the modelling, such as fluorescence. However our analysis of these plus other S082A flare observations (the latter containing Fe XV transitions between 321-482 angstrom), performed using the most recent Fe XV atomic physics calculations in conjunction with a chianti synthetic flare spectrum, indicate that blending of the lines is primarily responsible for the discrepancies. As a result, most Fe XV lines cannot be employed as electron density diagnostics for solar flares, at least at the spectral resolution of S082A and similar instruments (i.e.similar to 0.1 angstrom). An exception is the intensity ratio I(3s3p P-3(2)-3p(2) P-3(1))/I(3s3p P-3(2)-3p(2) D-1(2))=I(321.8 angstrom)/I(327.0 angstrom), which appears to provide good estimates of the electron density at this spectral resolution.

Alternative financing instruments for Spanish cooperative

The search for funding is an ongoing task of the company, which is exacerbated, particularly in times of economic crisis, affecting also to the cooperatives. Cooperative legislation available to these entities various instruments of external financing through the issuance of securities (bonds, equity securities, special shares), to them accounts are added in participation, but without much detail in the legal texts. At work we investigate their potential, by looking, especially in those last; We seek to clarify their legal status and contrast their potential as a technical instrument, alternative for funding in the area of cooperative societies. Finally, we also see the impact of the recent Law 5/2015, of promoting business financing in the cooperative sector and ended up proposing some policy adjustments.

Museums and youth: between misunderstanding and disappointment. Youth perceptions and arguments about the cultural consumption of museums in Chile

Young people are less explored in museum audience research; this is a paradoxical situation when considering its strategic location in the cultural reproduction and if considering the high performing cultural consumption compared with other sectors. The phenomenon of museums consumption by young Chileans who are self recognized as public and non-public museums is explored from a qualitative approach. It was conducted with focus groups in the three largest cities in Chile (Santiago, Valparaíso and Concepción). They identify the museum as a cultural institution in full force. However, in questioning museums activity youth reveal the specificity of their cultural matrix. This is referred to a social temporality based on the fragment, the discourse of familiarity, proximity and instead of breaking and critical. They claim a museum aesthetic / historical experience based on pleasure and enjoyment. An overview is proposed to further clarify the youth cultural consumption to characterize more precisely the place of the museum in the set, to design more effective policies museums.

"Cómo pintar el aire". Fundamentos científicos de la perspectiva atmosférica

La perspectiva aérea o atmosférica es juzgada por los pintores como parte esencial de la pintura, una vez establecidos los presupuestos geométricos de la representación naturalista mediante la perspectiva lineal. Leonardo da Vinci fue el primer autor en definir la perspectiva aérea o atmosférica, conocidos ya a través de L. B. Alberti los fundamentos geométricos de la perspectiva lineal en el tratado De Pictura (1435). Doscientos años después, tras la influyente publicación del Optics de Newton, contextualizadas bajo el espíritu racionalista del siglo XVIII, el artículo estudia las recomendaciones que desde la ciencia y los científicos (específicamente a través de tres figuras relevantes: Brook Taylor, J. H. Lambert y Gaspard Monge) se dan a los pintores con la pretensión de arbitrar una medición exacta del color, en confrontación con el tradicional empirismo del mundo artístico. Este tema puede considerarse un capítulo de gran interés en la larga historia de la pintura y la representación de los fenómenos atmosféricos, cuyos antecedentes teóricos tienen su inicio en el Débat sur le Coloris de la Académie Française del siglo XVII y sus resultados, conducirán hacia el nacimiento de la moderna Teoría del color, en respuesta a una cuestión tan compleja sobre cómo pintar el aire.