The scientific motivation of this thesis is to surpass some limitations in the state-of-the-art radiometers and spectropolarimeters used in Cosmic Microwave Background observations. The document follows the Three Papers Format of PhD theses. The first article, entitled A High Sensitivity Fourier Transform Spectrometer for Cosmic Microwave

HD 54662 AB is one of the three O + OB binaries known so far with orbital period longer than 1000 d, offering the opportunity to test scenarios of massive star formation and models of single stellar evolution. Here, we present a detailed study of this system based on new high-resolution spectra and data. A disentangling method is used to recover

We obtained time-resolved optical photometry and spectroscopy of the nova-like variable KR Aurigae in the low state. The spectrum reveals a DAB white dwarf (WD) and a mid-M dwarf companion. Using the companion star's i-band ellipsoidal modulation we refine the binary orbital period to be P = 3.906519 ± 0.000001 h. The light curve and the spectra

The support of the international astronomical community to the 2030 Agenda for Sustainable Development is fundamental to advance the rights and needs of the most vulnerable groups of our global society. Among these groups are the refugees.

The role of the magnetic fields in the formation and quenching of stars with different mass is unknown. We studied the energy balance and the star formation efficiency in a sample of molecular clouds in the central kpc region of NGC 1097, known to be highly magnetized. Combining the full polarization VLA/radio continuum observations with the HST/Hα

Aims: We report the discovery as well as the orbital and physical characterizations of two new transiting giant exoplanets, CoRoT-30 b and CoRoT-31 b, with the CoRoT space telescope. Methods: We analyzed two complementary data sets: photometric transit light curves measured by CoRoT, and radial velocity curves measured by the HARPS spectrometer. To