We present spectroscopy of nine planetary nebulae (PNe) in the outskirts of M31, all but one obtained with the 10.4 m GTC telescope. These sources extend our previous study of the oxygen abundance gradient of M31 to galactocentric radii as large as 100 kpc. None of the targets are bona fide members of a classical, metal-poor, and ancient halo. Two

We present the BaLROG (Bars in Low Redshift Optical Galaxies) sample of 16 morphologically distinct barred spirals to characterize observationally the influence of bars on nearby galaxies. Each galaxy is a mosaic of several pointings observed with the integral-field unit (IFU) SAURON leading to a tenfold sharper spatial resolution (˜100 pc)

We complement a recent Letter by Luo et al. by comparing the fraction of starburst galaxies that are interacting with the overall fraction of interacting galaxies in the nearby galaxy population (within ∼40 Mpc). We confirm that in starburst galaxies the fraction of interacting galaxies is enhanced, by a factor of around two, but, crucially, we do

The Kepler space mission provided near-continuous and high-precision photometry of about 207 000 stars, which can be used for asteroseismology. However, for successful seismic modeling it is equally important to have accurate stellar physical parameters. Therefore, supplementary ground-based data are needed. We report the results of the analysis of

Context. One of the difficulties in extracting reliable information about the thermodynamical and magnetic properties of solar plasmas from spectropolarimetric observations is the presence of light dispersed inside the instruments, known as stray light. Aims: We aim to analyze quiet Sun observations after the spatial deconvolution of the data. We

Reprocessing of the primary X-ray continuum in the accretion disc is expected to cause reverberation lags which are powerful diagnostics of the geometry of the inner flow. X-ray reverberation lags are now commonly observed in supermassive accreting black hole systems (active galactic nuclei, AGN). These lags are also expected in smaller objects