The existence of dark matter is probably one of the fundamental mysteries of modern science and unraveling its nature has become one of the primary goals of modern Physics. Despite representing 85% of all matter in the Universe, we do not know what it is. In its simplest description, it is made up of particles that interact with each other and with ordinary matter only through gravity. However, this description does not correspond to any physical model. Finding out what dark matter is requires finding evidence of some kind of interaction of dark matter that goes beyond gravity. In our work

The hierarchical model of galaxy evolution suggests that mergers have a substantial impact on the intricate processes that drive stellar assembly within a galaxy. However, accurately measuring the contribution of accretion to a galaxy's total stellar mass and its balance with in situ star formation poses a persistent challenge, as it is neither directly observable nor easily inferred from observational properties. Using data from MaNGA, we present theory-motivated predictions for the fraction of stellar mass originating from mergers in a statistically significant sample of nearby galaxies

There is increasing evidence that single-star evolutionary models are unable to reproduce all of the observational properties of massive stars. Binary interaction has emerged as a key factor in the evolution of a significant fraction of massive stars. In this study, we investigate the helium (Y(He)) and nitrogen surface abundances in a comprehensive sample of 180 Galactic O-type stars with projected rotational velocities of ≤150 km/s. We found a subsample (~20% of the total, and ~80% of the stars with Y(He) ≥ 0.12) with a Y(He) and nitrogen abundance combined pattern that is unexplainable by