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 SCUBA-2 850 μm observations of 13 candidate starbursting protoclusters selected using Planck and Herschel data. The cumulative number counts of the 850 μm sources in 9 of 13 of these candidate protoclusters show significant overdensities compared to the field, with the probability <10 -2 assuming the sources are randomly distributed in

We revisit the status of the new-physics interpretations of the anomalies in semileptonic B decays in light of the new data reported by Belle on the lepton-universality ratios R D(*) using the semileptonic tag and on the longitudinal polarization of the D * in B → D *τν, F L D ∗. The preferred solutions involve new left-handed currents or tensor

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

More than 4000 exoplanets are known to date in systems that differ greatly from our Solar System. In particular, inner exoplanets tend to follow orbits around their parent star that are much more compact than that of Earth. These systems are also extremely diverse, covering a range of intrinsic properties. Studying the main physi- cal processes at

In order to understand the diversity of classes observed in active galactic nuclei (AGNs), a geometrically and optically thick torus of gas and dust is required to obscure the central engine depending on the line of sight to the observer. We perform a simultaneous fitting of X-ray and mid-infrared (mid-IR) spectra to investigate whether the same