The project aims to observationally exploit  X-ray binaries, a research line in which our group it is one of the world leaders. These stellar systems, composed of a black hole (or a neutron star) and a solar-like star (companion), are unique laboratories to explore the behaviour of the matter and radiation under the most extreme gravitational fields. In particular, the gravity of the black hole is able to tear the material from the external layers of the companion, giving rise to the phenomenon of accretion. This physical process represents the most efficient form of energy production known. To characterise the accretion process is essential to understand the Universe, since it plays a crucial role in galactic and extra-galactic astrophysics.

The project seeks to characterise the general properties of cold winds that we have recently discovered in several X-ray binaries, as well as their influence on the accretion process and their impact on the interstellar medium. Likewise, we will investigate the relation of these cold winds with radio-jets and the winds observed in X-rays, with the final goal of testing, and modifying if necessary, the current paradigm of the accretion-ejection coupling in accreting black holes.