Planetary Nebulae (PNe) are the descendants of low- and intermediate-mass stars (0.8--8.0 M☉). The shape of the PN takes place at some point between the asymptotic giant branch (AGB) and the white dwarf (WD) stellar phases. Among the astrophysical phenomena, the PNe shows an impressive variety of complex morphologies. In fact, most of the PNe known

La forma habitual de medir el tamaño de las galaxias, el radio efectivo, es el resultado de una época cuando las imágenes astronómicas eran poco profundas y, por tanto, incapaces de capturar la extensión completa de las fuentes astronómicas. Esta situación ha cambiado drásticamente en la actualidad con la llegada de cartografiados muy profundos

En esta tesis se han abordado varios de los pasos necesarios (análisis del ruido instrumental, construcción de mapas, estimación de espectros de potencias) para el procesado de los datos de un experimento de polarización del Fondo Cósmico de Microondas (FCM), enfocándolos a la explotación cientı́fica del experimento QUIJOTE. En particular se

In this thesis, an extensive exploration of the low surface brightness Universe has been undertaken. A special emphasis has been placed on reducing the limitations arising from the use of integrated photometry, such as the residuals due to the observation and reduction of astronomical data, the effects of the point spread function and the presence

This thesis focuses on the study of LAEs and LBGs at z=3.4-6.8, a period of time between ~0.8-2 Gyr after the Big Bang, hosting the end of the reionisation epoch. To reach such deep galaxies, we have made use of the SHARDS survey of the GOODS-N field, with 200 h of exposure time with GTC. The 25 consecutive medium-band filters in the optical/NIR

We present the results of a study to discover prospective new white dwarf-L dwarf binaries as identified by their near-infrared excesses in the UKIDSS catalogue. We obtained optical spectra to validate the white dwarf nature for 22 of the candidate primary stars, confirming ten as white dwarfs and determining their effective temperatures and