The Adaptive Transient Hough method for long-duration gravitational wave transients

This paper describes a new semi-coherent method to search for transient gravitational waves of intermediate duration (hours to days). In order to search for newborn isolated neutron stars with their possibly very rapid spin-down, we model the frequency evolution as a power law. The search uses short Fourier transforms from the output of ground-based gravitational wave detectors and applies a weighted Hough transform, also taking into account the signal's amplitude evolution. We present the technical details for implementing the algorithm, its statistical properties, and a sensitivity estimate. A first example application of this method was in the search for GW170817 post-merger signals, and we verify the estimated sensitivity with simulated signals for this case.Comment: 13 pages, 14 figure

LISA observations of supermassive black holes: parameter estimation using full post-Newtonian inspiral waveforms

We study parameter estimation of supermassive black hole binary systems in the final stage of inspiral using the full post-Newtonian gravitational waveforms. We restrict our analysis to systems in circular orbit with negligible spins, in the mass range 10^8\Ms-10^5\Ms, and compare the results with those arising from the commonly used restricted post-Newtonian approximation. The conclusions of this work are particularly important with regard to the astrophysical reach of future LISA measurements. Our analysis clearly shows that modeling the inspiral with the full post-Newtonian waveform, not only extends the reach to higher mass systems, but also improves in general the parameter estimation. In particular, there are remarkable improvements in angular resolution and distance measurement for systems with a total mass higher than 5\times10^6\Ms, as well as a large improvement in the mass determination.Comment: Final version. Accepted for publication in Phys. Rev.

Movimiento, operación, acción y producción

En este artículo se parte de la distinción aristotélica de cuatro formas fundamentales de acción: enérgeia-kínesis (de la Metafisica) y praxis—potesis (de la Etica) y de las aportaciones de L. Polo en sus obras de Teoría del Conocimiento y de Èlica, especialmente, de sus conceptos de operación inmanente y movimiento transitivo, para establecer una tipología con las cuatro formas fundamentales de un dinamismo: proceso (kinesis), operación (enérgeia), acción (praxis) y producción (poiesis)

Els Molière de Joan Oliver

Joan Oliver admirava en la comèdia francesa clàssica l'elegància fluida del llenguatge, l'amenitat de l'anècdota i l'habilitat constructora de situacions i personatges, cosa que no era impediment, sinó al contrari, per aprofundir en el coneixement de la naturalesa humana. Oliver trobava en la comèdia francesa dels segles XVII i XVIII, i molt especialment en Molière, uns atractius dels quals mancava greument la tradició teatral catalana. Des d'aquesta perspectiva, l'escriptor va elaborar tres traduccions esplèndides, en vers, de tres comèdies de Molière, la primera de les quals va ser realitzada a l'exili de Santiago de Xile durant els anys quaranta del segle passat. Els epistolaris d'Oliver amb Xavier Benguerel i Josep Ferrater Mora ens permeten de resseguir l'esforç del traductor durant anys i el rigor i la sensibilitat que va esmerçar en les traduccions esmentades.In the French classical comedy, Joan Oliver admired the fluent elegance of language, the agreeableness of the anecdote and the constructive ability of situations and characters, which, far from being an obstacle, were useful to go deeper into the knowledge of human nature. In the French comedy of the XVII and XVIII centuries, and especially in Molière, Oliver could see some appeals which were seriously missing from the Catalan theatre tradition. From this perspective, the writer produced three magnificent translations, in verse, of three comedies written by Molière. The first of them was carried out during his exile in Santiago de Chile during the first forty years of the last century. The collected letters of Oliver with Xavier Benguerel and Josep Ferrater-Mora allow us to follow the effort the translator did for many years as well as the rigor and sensitivity he devoted to the aforementioned translations