It is now clear that central star binarity plays a key role in the formation and evolution of planetary nebulae, with a significant fraction playing host to close-binary central stars which have survived one or more common envelope episodes. Recent studies of these systems have revealed many surprises which place important constraints on the common

The Arches is one of the youngest, densest and most massive clusters in the Galaxy. As such it provides a unique insight into the lifecycle of the most massive stars known and the formation and survival of such stellar aggregates in the extreme conditions of the Galactic Centre. In a previous study we presented an initial stellar census for the

The black hole transient V404 Cygni exhibited a bright outburst in June 2015 that was intensively followed over a wide range of wavelengths. Our team obtained high time resolution optical spectroscopy (˜ 90 s), which included a detailed coverage of the most active phase of the event. We present a database consisting of 651 optical spectra obtained

Context. Rotational mixing is known to significantly affect the evolution of massive stars; however, we still lack a consensus regarding the various possible modeling approaches and mixing recipes describing this process. The empirical investigation of surface abundances of carbon, nitrogen, and oxygen (CNO) in large samples of O- and B-type stars

With the aim of using classic spectroscopic methods with high resolution and high signal-to-noise ratio in the NIR spectral window, we made a selection of 66 FGK-type stars observed with CARMENES, the brand-new, ultra-stable, double-channel spectrograph at the Spanish-German 3.5m Calar Alto telescope. These spectra are part of a CARMENES stellar

Minor mergers play a crucial role in galaxy evolution. UGC 10214 (the Tadpole galaxy) is a prime example of this process in which a dwarf galaxy has interacted with a large spiral galaxy ˜250 Myr ago and produced a perturbed disc and a giant tidal tail. We used a multi-wavelength dataset that partly consists of new observations (Hα, HI, and CO) and