http://hdl.handle.net/20.500.11765/1579 Wed, 23 Sep 2026 23:42:26 GMT 2026-09-23T23:42:26Z http://hdl.handle.net/20.500.11765/14875 Título : Metastable superpositions of ortho- and para-Helium states Autor : Sancho Sánchez, Pedro; Plaja, Luis Resumen : We analyze superpositions of ortho- and para-Helium states, considering the possible existence of stationary and metastable states in the system. In particular, the metastable superposition of 1s2s ortho and para states seems to be accessible to experimental scrutiny. Tue, 01 Jan 2008 00:00:00 GMT http://hdl.handle.net/20.500.11765/14875 2008-01-01T00:00:00Z http://hdl.handle.net/20.500.11765/14874 Título : Entanglement of unstable atoms: modifications of the emission properties Autor : Sancho Sánchez, Pedro; Plaja, Luis Resumen : We analyse the influence of entanglement on the emission properties of atoms. To this end, we firstly propose a scheme for the preparation of a pair of entangled helium atoms, one in the ortho- and the other in the para-spin configuration. We discuss a realistic scenario for this process, based on the double ionization of He by intense laser fields. These states are used to analyse disentanglement and the role of entanglement in the spontaneous emission from the pair. In particular, we show that the decaying rate of an entangled atom is different from that in a product state, modifying the temporal emission distribution and lifetime of the atoms. Thu, 01 Jan 2009 00:00:00 GMT http://hdl.handle.net/20.500.11765/14874 2009-01-01T00:00:00Z http://hdl.handle.net/20.500.11765/14669 Título : Convective rainfall rate multi-channel algorithm for Meteosat-7 and radar derived calibration matrices Autor : Luque, Ángel de; Gómez, I.; Manso Rejón, Marcelino Resumen : [EN]The CRR (Convective Rainfall Rate) algorithm was developed to detect intense mesoscale convective cells and to screen the most probable precipitation associated. It estimates rainfall intensity using the three bands of the Meteosat-7 and matrices calibrated with earth-based radars. Calibration matrices were performed following an accurate version of the Rainsat techniques but combining the infrared bands to detect convective clouds. Matrices were developed, up for the North of Europe, over the Baltic countries, with data from the radar of the Baltex Project provided by the SMHI (Swedish Meteorological and Hydrological Institute) and for the South of Europe, over the Iberian Peninsula, with radar data as provided by the INM (Spanish Meteorological Institute). In the present research, the CRR calibration methodology is validated, an analysis of calibration matrices differences in both areas over Europe is detailed and CRR resulting images are verified in a qualitative manner using rainfall radar images as ground true.; [ES]El algoritmo llamado CRR (Convective Rainfall Rate) ha sido desarrollado para detectar células convectivas mesoescalares y para monitorizar la precipitación asociada más probable. Es capaz de estimar intensidad de precipitación utilizando los tres canales del Meteosat-7 y matrices calibradas con datos de radares terrestres de precipitación. Estas matrices de precipitación han sido construidas a partir de las técnicas Rainsat pero combinando las dos bandas infrarrojas para favorecer la detección de nubosidad convectiva. Además, éstas han sido desarrolladas al norte del continente europeo sobre los países bálticos con datos de radar del proyecto Baltex proporcionados por el SMHI (Swedish Meteorological and Hydrological Institute) y al sur de Europa, sobre la Península Ibérica con datos de radar proporcionados por el INM (Instituto Nacional de Meteorología). En este trabajo se valida el método empleado de calibración de las matrices del CRR, se realiza un análisis de las matrices obtenidas al norte y sur de Europa, y finalmente una serie de imágenes CRR se verifican de forma cualitativa con respecto a las imágenes de radar. Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/20.500.11765/14669 2006-01-01T00:00:00Z http://hdl.handle.net/20.500.11765/14374 Título : The use of GIS to evaluate and map extreme maximum and minimum temperatures in Spain Autor : Luna Rico, Yolanda; Morata Gasca, Ana; Almarza Mata, Carlos; Martín Pérez, María Luisa Resumen : Spanish building legislation has recently changed and now requires an updated and restructured Technical Building Code which is in accordance with European directives. The norm contained in this Code is based on studies of extreme values for climatic elements such as temperature, precipitation and wind. Revised maps of extreme values for climatic elements with a 50-year recurrence interval are required. Here, extreme maximum and minimum temperature maps for Spain are evaluated and mapped by means of geographical information technology. The data are extracted from the historical database held by the Spanish Meteorological Institute. Daily extreme temperatures from 1,181 stations with records going back more than 30 years have been used. The maximum and minimum temperatures are determined as 50-year mean recurrence interval values. To obtain these values, a Gumbel distribution is fitted to the extreme annual values extracted from the database. Spatial interpolation in a regular 5 km×5 km grid of the annual maximum temperature is made by ordinary kriging. Meanwhile, for the annual minimum temperature a residual kriging has been applied due to its strong dependence on altitude. Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/20.500.11765/14374 2006-01-01T00:00:00Z