The CAST experiment: status and perspectives

The status of the solar axion search with the CERN Axion Solar Telescope (CAST) will be discussed. Results from the first part of CAST phase II where the magnet bores were filled with 4He gas at variable pressure in order to scan axion masses up to 0.4 eV will be presented. From the absence of excess X-rays when the magnet was pointing to the Sun, we set a typical upper limit on the axion-photon coupling of g < 2.17 x 10^10 GeV$-1 at 95% CL for axion masses lower than 0.4 eV, the exact result depending on the pressure setting. Our search for axions with masses up to about 1.2 eV using 3He as a buffer gas is in progress in the second part of CAST phase II. Expectations for sensibilities will be given. Near future perspectives as well as more long term options for a new helioscope experiment will be evoked.Comment: Proceedings of Identification of Dark Matter 2010-IDM2010 conferenc

Characterization of microbulk detectors in argon- and neon-based mixtures

A recent Micromegas manufacturing technique, so called Microbulk, has been developed, improving the uniformity and stability of this kind of detectors. Excellent energy resolutions have been obtained, reaching values as low as 11% FWHM at 5.9 keV in Ar+5%iC4H10. This detector has other advantages like its flexible structure, low material budget and high radio-purity. Two microbulk detectors with gaps of 50 and 25 um have been characterized in argon- and neon-based mixtures with ethane, isobutane and cyclohexane. The results will be presented and discussed. The gain curves have been fitted to the Rose-Korff gain model and dependences of the electron mean free path and the threshold energy for ionization have been obtained. The possible relation between these two parameters and the energy resolution will be also discussed.Comment: Submitted to the Journal of Instrumentatio

Open string axions and the flavor problem

We consider extensions of the standard model inspired by intersecting D-brane constructions, in order to address flavor mass textures. We include additional anomalous gauge symmetries, and scalar fields to break them and to generate Froggatt-Nielsen mass terms. Green-Schwarz axions are included to cancel mixed anomalies rendering the models consistent. At low energies, a residual anomalous global symmetry remains, and its associated pseudo-Goldstone mode becomes the physical axion, which can be interpreted as an axion arising from open string modes. General considerations show that such axions are very common in D-brane models and can be completely incompatible with current bounds. Astrophysical constraints are placed on the axion both by including neutrino masses in the Froggatt-Nielsen scheme and considering QCD instanton contributions to the axion mass. We find simple models where the axion decay constant is in the allowed range, but only one such minimal model with this property is free from excessive fine tunings elsewhere. We also note that generically addressing flavor textures for the CKM matrix leads to deconstructed extra dimensions.Comment: 30 pages, 2 figures. v2: references added. v3:typos fixe

Track reconstruction with MIMAC

Directional detection of Dark Matter is a promising search strategy. However, to perform such kind of detection, the recoiling tracks have to be accurately reconstructed: direction, sense and position in the detector volume. In order to optimize the track reconstruction and to fully exploit the data from the MIMAC detector, we developed a likelihood method dedicated to the track reconstruction. This likelihood approach requires a full simulation of track measurements with MIMAC in order to compare real tracks to simulated ones. Finally, we found that the MIMAC detector should have the required performance to perform a competitive directional detection of Dark Matter.Comment: 9 pages, 6 figures; Proceedings of the 3rd International conference on Directional Detection of Dark Matter (CYGNUS 2011), Aussois, France, 8-10 June 201

Three-dimensional track reconstruction for directional Dark Matter detection

Directional detection of Dark Matter is a promising search strategy. However, to perform such detection, a given set of parameters has to be retrieved from the recoiling tracks : direction, sense and position in the detector volume. In order to optimize the track reconstruction and to fully exploit the data of forthcoming directional detectors, we present a likelihood method dedicated to 3D track reconstruction. This new analysis method is applied to the MIMAC detector. It requires a full simulation of track measurements in order to compare real tracks to simulated ones. We conclude that a good spatial resolution can be achieved, i.e. sub-mm in the anode plane and cm along the drift axis. This opens the possibility to perform a fiducialization of directional detectors. The angular resolution is shown to range between 20$^\circ$ to 80$^\circ$, depending on the recoil energy, which is however enough to achieve a high significance discovery of Dark Matter. On the contrary, we show that sense recognition capability of directional detectors depends strongly on the recoil energy and the drift distance, with small efficiency values (50%-70%). We suggest not to consider this information either for exclusion or discovery of Dark Matter for recoils below 100 keV and then to focus on axial directional data.Comment: 27 pages, 20 figure

Análisis contrastivo en subtitulación y doblaje del slang juvenil y del lenguaje ofensivo y tabú de la serie Sex Education

El slang juvenil se encuentra estrechamente ligado a las variedades lingüísticas, más concretamente a los sociolectos y los idiolectos, y resulta impensable no concebirlo junto a otros lenguajes como el ofensivo y el tabú. En este sentido, la traducción audiovisual ha de adaptarse a estos tipos de lenguaje y sus respectivas expresiones, para así transmitir de forma correcta y precisa el mensaje, dada la notable evolución de mentalidad respecto a estas cuestiones que se ha generado estos últimos años, tanto en el ámbito audiovisual como en el social. Es por ello que, en este trabajo, hemos llevado a cabo un exhaustivo análisis contrastivo en subtitulación y doblaje del slang juvenil, el lenguaje ofensivo y tabú de la popular serie Sex Education. Para la elaboración de ese análisis, hemos recopilado un corpus bilingüe de expresiones de estos tipos de lenguaje de la serie en un glosario en el que incluimos la versión original junto a su traducción en ambas modalidades de TAV, los tipos de expresiones y una serie de observaciones en las que contrastamos la carga pragmática de ambas versiones traslativas, anotamos errores y proporcionamos una propuesta de traducción. Finalmente, hemos contrastado los resultados obtenidos con las hipótesis planteadas por ciertos estudiosos que han abordado la traducción del lenguaje ofensivo y tabú en subtitulado y doblaje, lo cual nos ha aportado resultados sorprendentes, ya que en la subtitulación observamos una tendencia a no suavizarlo tanto y el doblaje, que cuenta con mayor libertad que el subtitulado, no intensifica desmesuradamente este tipo de lenguaje.Grado en Traducción e Interpretació