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

The Λ cold dark matter (ΛCDM) paradigm of galaxy formation predicts that dense spheroidal stellar structures invariably grow at early cosmic time. These primordial spheroids evolve toward a virialized dynamical status as they finally become today's elliptical galaxies and large bulges at the center of disk galaxies. However, observations reveal

We report the discovery of two new pulsating extremely low-mass pre-white dwarf (pre-ELMV) candidates in the Transiting Exoplanet Survey Satellite (TESS) eclipsing binaries, TIC 149160359 and TIC 416264037. Their light curves show a typical feature of EL CVn-type binaries. The light-curve modeling indicates that they are both detached systems with

With a dayside temperature in excess of 4500 K, comparable to a mid-K-type star, KELT-9b is the hottest planet known. Its extreme temperature makes KELT-9b a particularly interesting test bed for investigating the nature and diversity of gas giant planets. We observed the transit of KELT-9b at high spectral resolution (R ∼ 94,600) with the CARMENES

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

We use models of stellar angular momentum evolution to determine ages for ∼500 stars in the APOGEE-Kepler Cool Dwarfs sample. We focus on lower-main-sequence stars, where other age-dating tools become ineffective. Our age distributions are compared to those derived from asteroseismic and giant samples and solar analogs. We are able to recover