With the help of CARMENCITA, the CARMENES Cool dwarf Information and daTa Archive (see SEA poster by Caballero et al.), we investigate the membership in double, triple or higher-order multiplicity systems of more than 1300 of the brightest, latest M dwarfs in the solar neighbourhood observable from Calar Alto. We use data compiled from the

This work investigates the effect of the aperture size on derived galaxy properties for which we have spatially-resolved optical spectra. We focus on some indicators of star formation activity and dust attenuation for spiral galaxies that have been widely used in previous work on galaxy evolution. We investigated 104 spiral galaxies from the CALIFA

We report striking changes in the broadband spectrum of the compact jet of the black hole transient MAXI J1836–194 over state transitions during its discovery outburst in 2011. A fading of the optical-infrared (IR) flux occurred as the source entered the hard-intermediate state, followed by a brightening as it returned to the hard state. The

We demonstrate in this work that it is possible to derive spectra of integrated absorption lines for any type stellar system using the GTC/OSIRIS Tunable Filters and a novel observing technique which allows for a reconstruction of the line profiles. The method has been successfully proven for the globular cluster system of VCC1261, a dwarf

Context. The derivation of the effective temperature of a star is a critical first step in a detailed spectroscopic analysis. Spectroscopic methods suffer from systematic errors related to model simplifications. Photometric methods may be more robust, but are exposed to the distortions caused by interstellar reddening. Direct methods are difficult

We report the discovery of a highly eccentric, double-lined spectroscopic binary star system (TYC 3010-1494-1), comprising two solar-type stars that we had initially identified as a single star with a brown dwarf companion. At the moderate resolving power of the MARVELS spectrograph and the spectrographs used for subsequent radial-velocity (RV)