It has been suggested that the X-shaped morphology observed in some radio sources can reflect either a recent merger of two supermassive black holes (SMBHs) or...

Aims: We have estimated black hole masses (M BH) for 14 gravitationally lensed quasars using Balmer lines; we also provide estimates based on MgII and CIV...

Context. Precise measurements of black hole masses are essential to understanding the coevolution of these sources and their host galaxies. Aims: We develop a...

Context. The extreme contrast ratios between stars and their planets at optical wavelengths make it challenging to isolate the light reflected by exoplanet...

Aims: During the last ~50 years, the population of black hole candidates in X-ray binaries has increased considerably, with 59 Galactic objects being detected...

Aims: We present a portrait of the active Centaur P/2010 C1 (Scotti), observed with a well developed comet-like activity (central diffuse coma condensation and...

Context. The evolution and fate of massive stars are thought to be affected by rotationally induced internal mixing. The surface boron abundance is a sensitive...

Context. Galaxy superclusters are the largest systems in the Universe that can give us information about the formation and evolution of the cosmic web. Aims: We...

Deep narrow band CCD images in the Hα , [O Iii] lambda5007 Ä, [N Ii] lambda6584 Ä, and [S Ii] lambda6717 +31 Ä emission lines have been obtained for the...