Triaxial Angular Momentum Projection and Configuration Mixing calculations with the Gogny force

We present the first implementation in the $(\beta,\gamma)$ plane of the generator coordinate method with full triaxial angular momentum and particle number projected wave functions using the Gogny force. Technical details about the performance of the method and the convergence of the results both in the symmetry restoration and the configuration mixing parts are discussed in detail. We apply the method to the study of $^{24}$Mg, the calculated energies of excited states as well as the transition probabilities are compared to the available experimental data showing a good overall agreement. In addition, we present the RVAMPIR approach which provides a good description of the ground and gamma bands in the absence of strong mixing.Comment: 40 pages,14 figure

The discrimination capabilities of Micromegas detectors at low energy

The latest generation of Micromegas detectors show a good energy resolution, spatial resolution and low threshold, which make them idoneous in low energy applications. Two micromegas detectors have been built for dark matter experiments: CAST, which uses a dipole magnet to convert axion into detectable x-ray photons, and MIMAC, which aims to reconstruct the tracks of low energy nuclear recoils in a mixture of CF4 and CHF3. These readouts have been respectively built with the microbulk and bulk techniques, which show different gain, electron transmission and energy resolutions. The detectors and the operation conditions will be described in detail as well as their discrimination capabilities for low energy photons will be discussed.Comment: To be published in the proceedings of the TIPP2011 conference (Physics Procedia

A new approach to bad news effects on volatility: the Multiple-Sign-Volume sensitive regime EGARCH model (MSV-EGARCH)

In this paper, using daily data for six major international stock market indexes and a modified EGARCH specification, the links between stock market returns, volatility and trading volume are investigated in a new nonlinear conditional variance framework with multiple regimes and volume effects. Volatility forecast comparisons, using the Harvey-Newbold test for multiple forecasts encompassing, seem to demonstrate that the MSV-EGARCH complex threshold structure is able to correctly fit GARCH-type dynamics of the series under study and dominates competing standard asymmetric models in several of the considered stock indexes.info:eu-repo/semantics/acceptedVersio

Efecto del número de indicadores por factor sobre la identificación y estimación en modelos aditivos de análisis factorial confirmatorio

La matriz multirrasgo-multimétodo (MRMM) es un diseño de investigación de larga tradición en Psicología. Las técnicas de análisis de datos adecuadas para una correcta extracción de conclusiones han estado sujetas a controversia. Parece, no obstante, que diversos modelos de análisis factorial confirmatorio resultan muy adecuados. De entre los diversos modelos, dos de ellos han recibido gran atención, el modelo completo, que apareció primero en la literatura, y el de unicidades correlacionadas, que parece una alternativa razonable a los problemas que aparecen en el primero. Los resultados de ambos modelos en la literatura se refieren a situaciones con un solo indicador por combinación rasgo-método. La presente investigación simula datos de matrices MRMM para múltiples indicadores por combinación rasgo-método y somete a prueba la adecuación de las estimaciones de ambos modelos. Los resultados apuntan a un mejor comportamiento del modelo completo, si bien los sesgos, aunque triviales en cuantía, aumentan conforme aumenta la correlación entre los métodos

Radiopurity of Micromegas readout planes

Micromesh Gas Amplification Structures (Micromegas) are being used in an increasing number of Particle Physics applications since their conception fourteen years ago. More recently, they are being used or considered as readout of Time Projection Chambers (TPCs) in the field of Rare Event searches (dealing with dark matter, axions or double beta decay). In these experiments, the radiopurity of the detector components and surrounding materials is measured and finely controlled in order to keep the experimental background as low as possible. In the present paper, the first measurement of the radiopurity of Micromegas planes obtained by high purity germanium spectrometry in the low background facilities of the Canfranc Underground Laboratory (LSC) is presented. The obtained results prove that Micromegas readouts of the microbulk type are currently manufactured with radiopurity levels below 30 microBq/cm2 for Th and U chains and ~60 microBq/cm2 for 40K, already comparable to the cleanest detector components of the most stringent low background experiments at present. Taking into account that the studied readouts were manufactured without any specific control of the radiopurity, it should be possible to improve these levels after dedicated development.Comment: 15 pages, 2 figure

Valoración conductimétrica continua de grupos carboxilos finales, en poliamidas.

El método que se propone se basa en una valoración condutimétrica, adaptable a un titulador automático de los grupos carboxílicos de poliamidas (6 y 6-6) por medio de una valoración de los iones anilinio formados al disolver la poliamida en anilina.The proposed method is based on a conductometric titration, adaptable to an automatic titrator of de carboxyl groups of polyamides (6 and 6-6) by means of he titration of the anilinium ions formed on dissolving polyamide in aniline.Peer Reviewe