We present long-slit, optical spectra of the merging system Arp220, obtained using the William Herschel Telescope (WHT) on La Palma. These data were taken as a...

We investigate the spectroscopic optical properties of gamma-ray sources detected with high significance above 50 GeV in the Third Catalog of Hard Fermi-LAT...

Context. Blazars are the most numerous class of high-energy (HE; E ∼ 50 MeV−100 GeV) and very high-energy (VHE; E ∼ 100 GeV−10 TeV) gamma-ray emitters...

Active galactic nuclei (AGNs) make up about 35 per cent of the more than 250 sources detected in very high-energy (VHE) gamma rays to date with the imaging...

Context. Blazars, which include BL Lacs and flat-spectrum radio quasars, represent the brightest persistent extragalactic sources in the high-energy (HE; 10 MeV...

We present the identification and characterization of the optical counterpart to 2XMM J011942.7+032421, one of the most luminous and distant ultra-luminous X...

We present accurate optical surface photometry in the U, B, V, R, and I passbands for 11 disk galaxies. The sample has been selected in order to study the...

This work presents the structural decomposition of a sample of 11 disk galaxies, which span a range of different morphological types. The U, B, V, R, and I...

This is the first paper of a series aimed at studying the structural and photometric properties in the optical band of a sample of 95 radio galaxies. Detailed...