Disentangling accretion disk and dust emissions in the infrared spectrum of type 1 AGN

We use a semi-empirical model to reproduce the 0.1-10um spectral energy distribution (SED) of a sample of 85 luminous quasars. In the model, the continuum emission from the accretion disk as well as the nebular lines are represented by a single empirical template (disk), where differences in the optical spectral index are reproduced by varying the amount of extinction. The near- and mid-infrared emission of the AGN-heated dust is modelled as the combination of two black-bodies (dust). The model fitting shows that the disk and dust components are remarkably uniform among individual quasars, with differences in the observed SED largely accounted for by varying levels of obscuration in the disk as well as differences in the relative luminosity of the disk and dust components. By combining the disk-subtracted SEDs of the 85 quasars, we generate a template for the 1-10um emission of the AGN-heated dust. Additionally, we use a sample of local Seyfert 1 galaxies with full spectroscopic coverage in the 0.37um to 39um range to demonstrate a method for stitching together spectral segments obtained with different PSF and extraction apertures. We show that the disk and dust templates obtained from luminous quasars also reproduce the optical-to-mid-infrared spectra of local Seyfert 1s when the contribution from the host galaxy is properly subtracted.Comment: 8 pages, 4 figures; accepted for publication in Frontiers in Astronomy and Space Sciences, Research Topic "Quasars at all cosmic epochs"; proceedings of the conference "Quasars at all cosmic epochs", held in Padova, April 2-7, 201

Albus 1: A very bright white dwarf candidate

We have serendipitously discovered a previously-unknown, bright source (B_T = 11.75+/-0.07 mag) with a very blue V_T-K_s color, to which we have named Albus 1. A photometric and astrometric study using Virtual Observatory tools has shown that it possesses an appreciable proper motion and magnitudes and colors very similar to those of the well known white dwarf G 191-B2B. We consider Albus 1 as a DA-type white dwarf located at about 40 pc. If confirmed its nature, Albus 1 would be the sixth brightest isolated white dwarf in the sky, which would make it an excellent spectrophotometric standard.Comment: ApJ Letters, in pres

Ranking Alternatives on the Basis of the Intensity of Dominance and Fuzzy Logic within MAUT

We introduce dominance measuring methods to derive a ranking of alternatives to deal with incomplete information in multi-criteria decision making problems on the basis of Multi-Attribute Utility Theory (MAUT). We consider the situation where the alternative performances are represented by uniformly distributed intervals, and there exists imprecision concerning the decision-makers¿ preferences, by means of classes of individual utility functions and imprecise weights represented by weight intervals or fuzzy weights, respectively. An additive multi-attribute utility model is used to evaluate the alternatives under consideration, which is considered a valid approach in most practical cases. The approaches we propose are based on the dominance values between pairs of alternatives that can be computed by linear programming, which are then transformed into dominance intensities from which a dominance intensity measure is derived. The methods proposed are compared with other existing dominance measuring methods and other methodologies by Monte Carlo simulation techniques. The performance is analyzed in terms of two measures of efficacy: hit ratio, the proportion of all cases in which the method selects the same best alternative as in the TRUE ranking, and the Rank-order correlation, which represents how similar the overall rank structures of alternatives are in the TRUE ranking and in the ranking derived from the method. The approaches are illustrated with an example consisting on the selection of intervention strategies to restore an aquatic ecosystem contaminated by radionuclides

Un antecedente de la Constitución de 1812. Teoría de una constitución política para España, escrita en 1805

Nos encontramos ante un hecho casi inédito en el constitucionalismo español: la publicación antes de 1812 de un texto que pretende ser, por un lado, guía y consejo de cómo elaborar una norma fundamental y, por otro, es un texto constitucional completo distribuido en partes («títulos» en la Constitución de 1812), capítulos y artículos. Esta obra se enmarca en dos ejes. Uno, el espíritu ilustrado de la Europa de fines del siglo XVIII. Sus ideas debieron llegar al sureste español a través de las ciudades de Orihuela y Murcia. Otro, la extensión de la Revolución francesa, en la medida en que la Ilustración no encuentra fórmulas pacíficas para solventar los problemas de la época. Sempere Guarinos, Floridablanca y el propio texto que comentamos, son un claro testigo, aunque desde posiciones diferentes, de lo que señalamos

Conceptos actuales sobre inervación de la superficie ocular

Investigación bibliográfica sobre la situación actual de los conocimientos de la inervación de la superficie ocular, centrándose en la córnea.Grado en Óptica y Optometrí