Understanding the connection between solar atmospheric layers through the magnetic field is a challenging task in solar physics. These regions are form by plasma weakly ionized and in some places the ionization fraction can be as low as 10^-4 meaning that the presence of neutrals could be important. The interaction of weakly ionized plasma with

This thesis addresses several topics in the study of the more massive and O-rich asymptotic giant branch (AGB) stars in our Galaxy. In particular, the main goals are the exploration of the circumstellar effects on the abundance determination in solar metallicity massive AGB stars by using more realistic pseudo-dynamical model atmospheres and the

El objetivo principal de esta tesis es estudiar la evolución de las galaxias formadoras de estrellas durante los últimos 7 Gyrs. Las galaxias formadoras de estrellas de alto desplazamiento al rojo (z>1) difieren de sus contrapartidas locales en varios aspectos clave. Sus regiones formadoras de estrellas son de un orden de magnitud más grandes y

Entre los grandes avances de la astronomía observacional de la última década se encuentra la misión espacial Gaia, la cual proporciona las posiciones, paralajes y movimientos propios más precisos hasta la fecha. Con más de mil millones de fuentes observadas, Gaia supone un incremento en tres órdenes de magnitud respecto a su predecesor Hipparcos

X-ray binaries are stellar systems composed of a neutron star or a black hole that accretes mass from a companion star. The transferred material carries angular momentum and an accretion disc is naturally formed around the compact object. There, the dissipative forces transform the potential energy of the gas into heat. In the process, the gas

This work presents the study of wave propagation and the Rayleigh-Taylor instability in the solar atmosphere using a two-fluid model. The solar atmosphere is strongly stratified and permeated by magnetic fields with a complex configuration, thus creating very different regimes throughout its layers. Of the different layers of the solar atmosphere