A new stellar library developed for stellar population synthesis modelling is presented. The library consists of 985 stars spanning a large range in atmospheric parameters. The spectra were obtained at the 2.5-m Isaac Newton Telescope and cover the range λλ 3525-7500 Å at 2.3 Å (full width at half-maximum) spectral resolution. The spectral

In these proceedings we give a summary of the characteristics and current status of the MEGARA instrument, the future optical IFU and MOS for the 10.4-m Gran Telescopio Canarias (GTC). MEGARA is being built by a Consortium of public research institutions led by the Universidad Complutense de Madrid (UCM, Spain) that also includes INAOE (Mexico)

We use Atacama Large Millimetre Array and Jansky Very Large Array observations of the galaxy cluster Cl J1449+0856 at z = 1.99, in order to study how dust-obscured star formation, interstellar medium content, and active galactic nuclei activity are linked to environment and galaxy interactions during the crucial phase of high-z cluster assembly. We

Emission lines from metals offer one of the most promising ways to detect the elusive warm-hot intergalactic medium (WHIM; 105 T 107K), which is thought to contain a substantial fraction of the baryons in the low-redshift Universe. We present predictions for the soft X-ray line emission from the WHIM using a subset of cosmological simulations

Spectroscopic data of two relatively [O III]-luminous planetary nebulae (PNe) have been obtained with the 10.4 m Gran Telescopio Canarias. M174 and M2496 are each ~1° from the center of M31 along opposite sides of its minor axis. The ensemble of these 2 distant PNe plus 16 similarly luminous outer-disk PNe published previously by Kwitter et al

Dependence of phenomenological properties of Cepheids on the heavy element abundance is studied. It is found that the amplitude of the pulsation depends on the metallicity of the stellar atmosphere.